problem with Dimplex Duo300n heaters

[Agaxyz]

Hello, I’m not an electrician and I have a question in relation to Dimplex Duo300n.

Some background information: a couple of months ago I have moved into the property where those heaters are in place (there is 5 of them).

The people who used to live in this apartment before, used RXPW4 control panel for majority of them (they also said all heaters were working). It was end of summer when I moved in, so I switched off this central RXPW4 control panel as I did not need that much heat during the day and planned on only using the heat from the night storage.

• One of the heaters, seems not to be previously connected to this main control panel plus it has been on all the time (even at the end of the summer) for the night storage only and it works perfectly – this heater just an example how those heaters can work.
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• The 2nd heater once I turned it on by turning all 3 switches on on the wall, had a constant buzzing noise. Well, I was told by the previous tenants that sometimes the heaters might give clicking, buzzing noises when turned on but I did not assume it might be for that long, as once I turned on that one and it was buzzing for 30 min, at the end I turned off as it must be simply broken. I do not know if it would store the heat overnight because I’m not going to leave it on with that buzzing noise for the whole night. Having said that, I did run the diagnostic on it (the link will be below) and somehow the result came as the 2nd bar from the top flashing so it should not have a problem? But this constant buzzing?

However, the most important question I have is in relation to 3 other heaters – they do not seem to store the heat overnight (even though I would set the overnight storage temperature to max or one bar below max) though they would “work” on the day tariff. The description on how they actually work is below:

• The 3rd heater, once turned on (what I mean by that is turning on all 3 switches on the wall) is slightly buzzing for a couple of seconds. Next the noise stops. Again does not store the heat overnight. For the day heating, it starts to heat when there are 8 read bars on the heater day control panel. However, it stops heating on its own after about 10 -20 minutes, even though the temperature in the room is less than 21C. It seems to heat constantly when all 9 indicators are red. So it does not heat when there is anything between 1 to 7 red bars on the control system. The heating it provides when on level 9 is not as strong as the heating provided by heater no 3 (described below).
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• The 4th heater once turned on is quiet so this is ok. Again it does not store the heat overnight either. For the day heating, it starts to heat when there are 3 read bars on the heater control panel. However, it stops heating on its own after about 20 minutes, even though the temperature in the room is less than 21C. When I increase the heat control to 4 red bars it also heats up only for about 20 min and turns itself off. It seems to be heating constantly when there are 5 red bars on the control panel for the day heating.
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• The 5th heater, once turned on is also quiet so this is ok. Again, it does not store the heat overnight. For the day heating, it starts to heat when there are 3 read bars on the heater control panel. However, it stops heating on its own after about 50 minutes, even though the temperature in the room is less than 21C. When I increase the heat control to 4 red bars, it seems to work constantly and provides better/warmer heat at this level 4 than heater no 1 at level 9.

What I did so far to try to sort this out is below plus my questions as well:

• I found the video how to run the diagnostic, the link is here
  , did it for all 4 heaters and all the them had the 2nd bar from the top flashing so they seem to pass, all is fine somehow? Why would they not store the heat overnight than?
• I turned all 3 heaters (= heater no 3,4,5) off for the couple of hours and back on – no change, still do not store heat overnight
• I turned all 3 heaters off for about 10 second and back on – no change, still do not heat overnight
• Shall I try to turn them off and on almost immediately? Maybe this somehow will “kick start them?”
• I thought that maybe I should set up this RXPW4 control panel so the heat comes during the night (not as a background/night system, but maybe somehow on the day system will turn itself on during the night though it will be at a night rate so still cheaper?), in that case I could heat up the flat at night. However, once I waited deep into the night when the night electrical tariff comes on and turn on a couple of bars for the day tariff on each of 3 heaters – nothing happened, they stayed cold (not surprise here as it was night not day, but it was just an idea worth trying…)

As mentioned, the previous tenants told me that all heaters worked well when they lived here. It does seem a bit odd that 3 of them suddenly stopped working properly by not even storing the heat overnight….

I was also told that it might sound like the room temperature has a fault however Dimplex Heater no longer making parts for this heater (those heaters were discontinued). Additionally, I was told that there might a loose connection or they might need a heater full replacement (I cannot afford this).

Would anybody have any better idea what the problem/s might be for each of those heaters? What might help, what I might still try to do? Would calling an electrician to look at in person help if there are not parts for those heaters?

Thank you very, very much for reading this whole story. Hopefully there will a solution to all of this.

 

[Avo Mk8]

You are not alone, there have been a few posts on this forum with people having such problems - search 'Dimplex Duo'

Is there a separate E7 night rate feed to your heaters from a dedicated off-peak consumer unit? If so, ensure that's 'on' and the individual breakers/ fuses are OK ! Since several heaters suffer from the same problem, I'm inclined to think there may be a supply or other common issue. An electrician would be able to check the off-peak feed to the heaters.

Some parts, such as thermostats and elements, are still available, eg through eBay (!), so if you don't feel competent to do the electrical detective work, you may be able to find someone willing to at least have a look.

I'm afraid the chances of diagnosing the cause of such faults over the web may be pretty slim

 

[Agaxyz]

You are not alone, there have been a few posts on this forum with people having such problems - search 'Dimplex Duo'

Is there a separate E7 night rate feed to your heaters from a dedicated off-peak consumer unit? If so, ensure that's 'on' and the individual breakers/ fuses are OK ! Since several heaters suffer from the same problem, I'm inclined to think there may be a supply or other common issue. An electrician would be able to check the off-peak feed to the heaters.

Some parts, such as thermostats and elements, are still available, eg through eBay (!), so if you don't feel competent to do the electrical detective work, you may be able to find someone willing to at least have a look.

I'm afraid the chances of diagnosing the cause of such faults over the web may be pretty slim

Thank you for the tip in relation to "Dimplex Duo" and all the other advice. I would say there is a separate E7 feed. Will probably have to ask an electrician to look at it, thought I was also advised that maybe I should put both the heating for the whole day and whole night on max and see what will happen than...? Would you say that if I start control them again via the main control panel they might start working? Is is possible that turning this main control panel off a while ago, might have triggered something and all of them stopped working?

 

[Avo Mk8]

Thank you for the tip in relation to "Dimplex Duo" and all the other advice. I would say there is a separate E7 feed. Will probably have to ask an electrician to look at it, thought I was also advised that maybe I should put both the heating for the whole day and whole night on max and see what will happen than...? Would you say that if I start control them again via the main control panel they might start working? Is is possible that turning this main control panel off a while ago, might have triggered something and all of them stopped working?

It is worth trying the main control panel. I believe these heaters are about 15 years old, and it is possible that turning the power off to the controller (if that's what you did) has caused a backup battery in it to give up, or some electronic fault, but that's unlikely.
I don't think playing with combinations of settings will achieve anything.

You are aware that to charge up a storage heater, ie to heat up the storage medium, it has to be on for quite a few hours before it's able to give out much heat (but that also relies on the controls working of course!).

 

[Agaxyz]

It is worth trying the main control panel. I believe these heaters are about 15 years old, and it is possible that turning the power off to the controller (if that's what you did) has caused a backup battery in it to give up, or some electronic fault, but that's unlikely.
I don't think playing with combinations of settings will achieve anything.

You are aware that to charge up a storage heater, ie to heat up the storage medium, it has to be on for quite a few hours before it's able to give out much heat (but that also relies on the controls working of course!).

The building was built about 11/12 years ago so this is how old the heaters here are. If turning the main RXPW4 control panel off might have caused a back up battery in it to give up, would it be possible for this battery to start working again just by turning this panel on again? Sorry, again I'm not electrician so not sure how it works. From my understanding all those heaters should work as an individual units, without being connected or controlled via RXPW4. And this is what heater no 1 does.

 

[Avo Mk8]

The building was built about 11/12 years ago so this is how old the heaters here are. If turning the main RXPW4 control panel off might have caused a back up battery in it to give up, would it be possible for this battery to start working again just by turning this panel on again? Sorry, again I'm not electrician so not sure how it works

I don't even know for sure if there is such a battery In the unit. I was just suggesting a possibility. And indeed after power is restored the battery should charge up and everything work again. But 10 year old batteries can be unpredictable.

I agree the units should work by themselves. I was thinking that if several of them were suffering from similar symptoms, it migt be from some outside influence, like a problem with E7, rather than each unit having developed an individual fault.

I don't have anything else to suggest. If you can satisfy yourself that both the normal rate supply and the off-peak supply are present at the heaters (assuming that is the intended arrangement), then you need help from someone experienced at repairing such appliances.

 

[Agaxyz]

I don't even know for sure if there is such a battery In the unit. I was just suggesting a possibility. And indeed after power is restored the battery should charge up and everything work again. But 10 year old batteries can be unpredictable.

I agree the units should work by themselves. I was thinking that if several of them were suffering from similar symptoms, it migt be from some outside influence, like a problem with E7, rather than each unit having developed an individual fault.

I don't have anything else to suggest. If you can satisfy yourself that both the normal rate supply and the off-peak supply are present at the heaters (assuming that is the intended arrangement), then you need help from someone experienced at repairing such appliances.

Ok, thank you for trying to help. I just checked with the previous tenants and previously all heaters including the water immersion heater were controlled by this panel. So now this one heater in the corridor, close to water heater works ( the water heater also works) and the rest not, probably there must be some kind of connection between those not working on night rate heater or just by bizzare luck they stopped working at the same time, rather strange - I will talk to the electrician. But the last question I have is: as mentioned previously once I waited till the electricity night rate starts (for an example lets assume it starts at midnight) and turn the day heating on at 1am on all 3 heaters. They did not work. Lets call this situation scenario 1. So last night I turned them on an hour before the night rate starts (so lets say at 23:00), so they were working on a day system, and I kept this day system on when the night rate started at midnight. Somehow they kept on heating. Next, I wanted to see if maybe they kicked off and started to heat on the night rate so about 01:15 I turn the day heating off and ...they stopped heating... (let's call it scenario 2) I just do not understand how come they did not heat up on the day system in scenario 1 but kept on heating on a day rate in scenario 2 - the only difference being that in scenario 2 day heating system was on when the night rate and night heating system should have started. I kind of thought that they would or should turn themselves off automatically when the night heating system kicks in. Would this normally happen, if their night storage system was working properly? Or if the day heating system is on when the night heating should start, the day heating will also stays on?

 

[Avo Mk8]

Ok, thank you for trying to help. I just checked with the previous tenants and previously all heaters including the water immersion heater were controlled by this panel. So now this one heater in the corridor, close to water heater works ( the water heater also works) and the rest not, probably there must be some kind of connection between those not working on night rate heater or just by bizzare luck they stopped working at the same time, rather strange - I will talk to the electrician. But the last question I have is: as mentioned previously once I waited till the electricity night rate starts (for an example lets assume it starts at midnight) and turn the day heating on at 1am on all 3 heaters. They did not work. Lets call this situation scenario 1. So last night I turned them on an hour before the night rate starts (so lets say at 23:00), so they were working on a day system, and I kept this day system on when the night rate started at midnight. Somehow they kept on heating. Next, I wanted to see if maybe they kicked off and started to heat on the night rate so about 01:15 I turn the day heating off and ...they stopped heating... (let's call it scenario 2) I just do not understand how come they did not heat up on the day system in scenario 1 but kept on heating on a day rate in scenario 2 - the only difference being that in scenario 2 day heating system was on when the night rate and night heating system should have started. I kind of thought that they would or should turn themselves off automatically when the night heating system kicks in. Would this normally happen, if their night storage system was working properly? Or if the day heating system is on when the night heating should start, the day heating will also stays on?

Hi
Presumably you have the instruction leaflets for the radiator and the control panel?
When you say 'kept on heating' and 'stopped heating' you are presumably referring to what the indicator lights are showing?
It seems the controls are doing something, even if we can't make sense of it!

When it comes to actual heat output, the only element you would be aware of being hot in the short term is the radiant one. The off peak element is buried in the thermal store, so it would take quite a while for heat to appear from that.

I also remembered there is a thermal fuse for the storage part of the heater, so there is a possible explanation for the stored heat not working, although if the heaters worked for the previous owners it seems very unlikely that three units would all suffer from that.

There's lots of info on the web on these units, and it seems spares are still available (not made by Dimplex, but supported by them I think)

https://www.dimplex.co.uk/sites/default/files/assets//DuoHeat_N_Installation_Instructions_Issue_5.pdf

Module pcb REPAIR SERVICE Storage heater Dimplex Duoheat 300n 330 etc N 87389B | eBay

Any Storage Heater. Brief Fault Symptoms. This is a Repair Service. Test and repair of your module/pcb What you need to do. Quality House. Quality Electronic Repairs.

www.ebay.co.uk

PS That link is not because I think your module is faulty - it was just to let you know in case such parts turn out to need attention!

 

[Agaxyz]

Hi
Presumably you have the instruction leaflets for the radiator and the control panel?
When you say 'kept on heating' and 'stopped heating' you are presumably referring to what the indicator lights are showing?
It seems the controls are doing something, even if we can't make sense of it!

When it comes to actual heat output, the only element you would be aware of being hot in the short term is the radiant one. The off peak element is buried in the thermal store, so it would take quite a while for heat to appear from that.

I also remembered there is a thermal fuse for the storage part of the heater, so there is a possible explanation for the stored heat not working, although if the heaters worked for the previous owners it seems very unlikely that three units would all suffer from that.

There's lots of info on the web on these units, and it seems spares are still available (not made by Dimplex, but supported by them I think)

https://www.dimplex.co.uk/sites/default/files/assets//DuoHeat_N_Installation_Instructions_Issue_5.pdf

Module pcb REPAIR SERVICE Storage heater Dimplex Duoheat 300n 330 etc N 87389B | eBay

Any Storage Heater. Brief Fault Symptoms. This is a Repair Service. Test and repair of your module/pcb What you need to do. Quality House. Quality Electronic Repairs.

www.ebay.co.uk

PS That link is not because I think your module is faulty - it was just to let you know in case such parts turn out to need attention!

In terms of 'kept on heating' and 'stopped heating' - yes in relation to the situation 1 I turned the day panel on, so the days lights/indicators were on, it was 1am but the heat was not produced. The night rates for than example starts at midnight. In terms of situation 2 the day lights/indicators were on from 23:00ish till 1:15ish in the morning and as long as they were on the heat was produced. Once I turned the day lights off the heat was stopped being produced. I do have instruction etc but there is nothing about problem solving/troubleshooting. I assume if I call the electrician and explain the problem over the phone, when he/she comes they would have at least those thermal fuses or some parts to try to solve this on the spot, if possible? Not sure what equipments and parts the electricians on avage carry with them. Again thank you for your help.

 

[Avo Mk8]

In terms of 'kept on heating' and 'stopped heating' - yes in relation to the situation 1 I turned the day panel on, so the days lights/indicators were on, it was 1am but the heat was not produced. The night rates for than example starts at midnight. In terms of situation 2 the day lights/indicators were on from 23:00ish till 1:15ish in the morning and as long as they were on the heat was produced. Once I turned the day lights off the heat was stopped being produced. I do have instruction etc but there is nothing about problem solving/troubleshooting. I assume if I call the electrician and explain the problem over the phone, when he/she comes they would have at least those thermal fuses or some parts to try to solve this on the spot, if possible? Not sure what equipments and parts the electricians on avage carry with them. Again thank you for your help.

Thanks for the explanation.

One thing I'm not sure about is what happens to the local controls when the pilot wire is connected to the RXPW4 controller.
You mentioned the one heater that is not connected to the controller works fine.
I wondered if the heaters with their pilot wire to the controller were overridden by the settings of the controller, or maybe the controller has to be on a particular setting for the heater buttons to work. Just a thought.
It might be worth the electrician disconnecting a pilot wire (it's at mains voltage!) and seeing if that changes the behaviour of that heater!

 

[Agaxyz]

Thanks for the explanation.

One thing I'm not sure about is what happens to the local controls when the pilot wire is connected to the RXPW4 controller.
You mentioned the one heater that is not connected to the controller works fine.
I wondered if the heaters with their pilot wire to the controller were overridden by the settings of the controller, or maybe the controller has to be on a particular setting for the heater buttons to work. Just a thought.
It might be worth the electrician disconnecting a pilot wire (it's at mains voltage!) and seeing if that changes the behaviour of that heater!

I've talked to the previous tenants and they said the the heater that works fine was also connected to the RXPW4 controller plus the water heater (and it used and keeps on working fine) as well. So it seems when I moved in all of the heaters plus the water heater were connected. Next after a couple of days/weeks I switched that controller off and the heater that used to store overnight keeps on working, the water heater keeps on heating the water and the other 3 heaters don't work = do not store overnight (plus one is totally broken as it has constant buzzing noise when I turn this on). So nothing is connected to the RXPW4 now and all of them should be able to work as on it's own. I understand that maybe the pilot wire might have been overridden and that might need to be fixed somehow. Yet, now when I think about it I never ever felt any warmth in the mornings from those 3 heaters when the controller was still on, at least as I remember. Hmmmm, not sure if I switch this controller on now, will it show the way it was set up previously (just so I could see) or would I have to set it up from the start. To be honest I'm not eager to switch it on as I am afraid it might mess up the heater that is still working plus the water heater.... Is it possible for you to recommend someone who would be familiar with those heaters and might be able to help?

 

[Avo Mk8]

I've talked to the previous tenants and they said the the heater that works fine was also connected to the RXPW4 controller plus the water heater (and it used and keeps on working fine) as well. So it seems when I moved in all of the heaters plus the water heater were connected. Next after a couple of days/weeks I switched that controller off and the heater that used to store overnight keeps on working, the water heater keeps on heating the water and the other 3 heaters don't work = do not store overnight (plus one is totally broken as it has constant buzzing noise when I turn this on). So nothing is connected to the RXPW4 now and all of them should be able to work as on it's own. I understand that maybe the pilot wire might have been overridden and that might need to be fixed somehow. Yet, now when I think about it I never ever felt any warmth in the mornings from those 3 heaters when the controller was still on, at least as I remember. Hmmmm, not sure if I switch this controller on now, will it show the way it was set up previously (just so I could see) or would I have to set it up from the start. To be honest I'm not eager to switch it on as I am afraid it might mess up the heater that is still working plus the water heater.... Is it possible for you to recommend someone who would be familiar with those heaters and might be able to help?

Might be worth phoning Dimplex customer services to find out if there is a Dimplex expert in your area

Sorry to cover old ground, but presumably you have set up 'background' heat (the storage bit) as per the instructions?

https://www.dimplex.co.uk/sites/default/files/assets//DuoHeat_N_GDC_Operating_Instructions_Issue_1.pdf

A heater buzzing seems to indicate the pcb module requires replacing. A replacement is around £100, or to have it repaired see my previous link. You will need a cooperative engineer, because I suspect many will suggest the units should be changed due to their older technology.
A new energy law was passed in 2018 "LOT 20", which requires electric heaters to comply with 'efficiency' requirements, (which your's don't meet), so some may suggest that is a reason to upgrade. However that's not mandatory.

I hope you can find someone to persevere and get to the bottom of the problem. If these heaters are a feature of other apartments around you, might be worth asking other residents who they used to fix any faults?

 

[Agaxyz]

Might be worth phoning Dimplex customer services to find out if there is a Dimplex expert in your area

Sorry to cover old ground, but presumably you have set up 'background' heat (the storage bit) as per the instructions?

https://www.dimplex.co.uk/sites/default/files/assets//DuoHeat_N_GDC_Operating_Instructions_Issue_1.pdf

A heater buzzing seems to indicate the pcb module requires replacing. A replacement is around £100, or to have it repaired see my previous link. You will need a cooperative engineer, because I suspect many will suggest the units should be changed due to their older technology.
A new energy law was passed in 2018 "LOT 20", which requires electric heaters to comply with 'efficiency' requirements, (which your's don't meet), so some may suggest that is a reason to upgrade. However that's not mandatory.

I hope you can find someone to persevere and get to the bottom of the problem. If these heaters are a feature of other apartments around you, might be worth asking other residents who they used to fix any faults?

Frist of all, whoever you are thank you so very, very much for continuously trying to help, to find solution, to understand what is really going on also by asking the ground questions - you have lots of patience

Good idea I will call Dimplex, but if someone comes to your mind, please do let me know, I live in Oxfordshire.

Ok so starting from the last bit - people in the apartments around, just try to put up with them not working, or partially working, for some they are working ok, it seems nobody called an electrician yet or maybe if they did it was unsuccessful or maybe someone was told they would have to replace them and that is very expensive - nobody has suggested any electrician though I asked.

The heating is set up as follows:
1st heater the one that works, the background is set up for the 8th bar so it would be 7th red bar but as per the instructions you provided the link to, this blue light/bar should also be counted in), the comfort zone is on a blue light = the 1st bar . It produces a lot of heat from the night storage, till very late in the afternoon and sometimes even evening, so no point to have comfort zone on anything more than this blue light. This background and the comfort zone where like this when I took over the flat, I did not change it and it works perfectly

As I understand/think all other heaters should work as this one: accumulate enough heat overnight to share it during the day. Turning the comfort zone on, would only really be necessary in extra freezing temperatures if the storage heat would not be enough to heat up the place. Am I correct? Because, as per the instructions you have provided it seems for both the normal and the high setting the comfort zone should be on the 5th bar constantly? It does not make a sense for me as what is the point for using the comfort zone if the background zone provides the heat? Plus there is an electricity day charge for a comfort zone. I am a bit confused about it now. Anyway back to the heaters.

The 2nd heater is broke so will leave it.

The 3rd heater, the background (when I 1st checked it) was initially somewhere in the middle more or less (for sure more than 4 red bars). However, as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 9th bar. The comfort zone is on 1st = on a blue light.

The 4th heater, the background ( again when I 1st checked it) was initially somewhere in the middle more or less (again more than 4 bars). However, the same story as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 10th bar so it is max. The comfort zone is on 1st = on a blue light.

The 5th heater, the background ( again when I 1st checked it) was initially somewhere in the middle more (more than 4 red bars) or less. However, the same story as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 9th bar so it is max. The comfort zone is on 1st = on a blue light.

I have 3 switches on the wall for each of them. Also the instructions I have are slightly older than yours. As those heaters have been operating supposively for years, it does say in my instructions that I can adjust temperature by adding or removing one red light.

Would you say I should change those settings now? Again a bit confused about this comfort zone now, if heater no 1 works perfectly when comofor zone is on blue.

 

[Agaxyz]

Frist of all, whoever you are thank you so very, very much for continuously trying to help, to find solution, to understand what is really going on also by asking the ground questions - you have lots of patience

Good idea I will call Dimplex, but if someone comes to your mind, please do let me know, I live in Oxfordshire.

Ok so starting from the last bit - people in the apartments around, just try to put up with them not working, or partially working, for some they are working ok, it seems nobody called an electrician yet or maybe if they did it was unsuccessful or maybe someone was told they would have to replace them and that is very expensive - nobody has suggested any electrician though I asked.

The heating is set up as follows:
1st heater the one that works, the background is set up for the 8th bar so it would be 7th red bar but as per the instructions you provided the link to, this blue light/bar should also be counted in), the comfort zone is on a blue light = the 1st bar . It produces a lot of heat from the night storage, till very late in the afternoon and sometimes even evening, so no point to have comfort zone on anything more than this blue light. This background and the comfort zone where like this when I took over the flat, I did not change it and it works perfectly

As I understand/think all other heaters should work as this one: accumulate enough heat overnight to share it during the day. Turning the comfort zone on, would only really be necessary in extra freezing temperatures if the storage heat would not be enough to heat up the place. Am I correct? Because, as per the instructions you have provided it seems for both the normal and the high setting the comfort zone should be on the 5th bar constantly? It does not make a sense for me as what is the point for using the comfort zone if the background zone provides the heat? Plus there is an electricity day charge for a comfort zone. I am a bit confused about it now. Anyway back to the heaters.

The 2nd heater is broke so will leave it.

The 3rd heater, the background (when I 1st checked it) was initially somewhere in the middle more or less (for sure more than 4 red bars). However, as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 9th bar. The comfort zone is on 1st = on a blue light.

The 4th heater, the background ( again when I 1st checked it) was initially somewhere in the middle more or less (again more than 4 bars). However, the same story as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 10th bar so it is max. The comfort zone is on 1st = on a blue light.

The 5th heater, the background ( again when I 1st checked it) was initially somewhere in the middle more (more than 4 red bars) or less. However, the same story as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 9th bar so it is max. The comfort zone is on 1st = on a blue light.

I have 3 switches on the wall for each of them. Also the instructions I have are slightly older than yours. As those heaters have been operating supposively for years, it does say in my instructions that I can adjust temperature by adding or removing one red light.

Would you say I should change those settings now? Again a bit confused about this comfort zone now, if heater no 1 works perfectly when comofor zone is on blue.

All 3 switches on the wall for each of them, except no 2, are on.

 

[Avo Mk8]

Frist of all, whoever you are thank you so very, very much for continuously trying to help, to find solution, to understand what is really going on also by asking the ground questions - you have lots of patience

Good idea I will call Dimplex, but if someone comes to your mind, please do let me know, I live in Oxfordshire.

Ok so starting from the last bit - people in the apartments around, just try to put up with them not working, or partially working, for some they are working ok, it seems nobody called an electrician yet or maybe if they did it was unsuccessful or maybe someone was told they would have to replace them and that is very expensive - nobody has suggested any electrician though I asked.

The heating is set up as follows:
1st heater the one that works, the background is set up for the 8th bar so it would be 7th red bar but as per the instructions you provided the link to, this blue light/bar should also be counted in), the comfort zone is on a blue light = the 1st bar . It produces a lot of heat from the night storage, till very late in the afternoon and sometimes even evening, so no point to have comfort zone on anything more than this blue light. This background and the comfort zone where like this when I took over the flat, I did not change it and it works perfectly

As I understand/think all other heaters should work as this one: accumulate enough heat overnight to share it during the day. Turning the comfort zone on, would only really be necessary in extra freezing temperatures if the storage heat would not be enough to heat up the place. Am I correct? Because, as per the instructions you have provided it seems for both the normal and the high setting the comfort zone should be on the 5th bar constantly? It does not make a sense for me as what is the point for using the comfort zone if the background zone provides the heat? Plus there is an electricity day charge for a comfort zone. I am a bit confused about it now. Anyway back to the heaters.

The 2nd heater is broke so will leave it.

The 3rd heater, the background (when I 1st checked it) was initially somewhere in the middle more or less (for sure more than 4 red bars). However, as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 9th bar. The comfort zone is on 1st = on a blue light.

The 4th heater, the background ( again when I 1st checked it) was initially somewhere in the middle more or less (again more than 4 bars). However, the same story as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 10th bar so it is max. The comfort zone is on 1st = on a blue light.

The 5th heater, the background ( again when I 1st checked it) was initially somewhere in the middle more (more than 4 red bars) or less. However, the same story as it was not working a neighbour suggested turning it to max, to help it kick start it, just for the night. I did it but it did not work. Now the background is on the 9th bar so it is max. The comfort zone is on 1st = on a blue light.

I have 3 switches on the wall for each of them. Also the instructions I have are slightly older than yours. As those heaters have been operating supposively for years, it does say in my instructions that I can adjust temperature by adding or removing one red light.

Would you say I should change those settings now? Again a bit confused about this comfort zone now, if heater no 1 works perfectly when comofor zone is on blue.

It seems you are doing all the right things with the controls.
Yes the idea is to have background turned up enough to give you the heat you need through most of the day, and as you say, you probably don't need much, if any, comfort heating at all. Since the elements are not being switched on by the controllers, in the ones that don't work, for some reason, it really doesn't matter how you leave them set at the moment!

The frustrating thing is that what you really need at this point is a competent engineer with a multimeter (preferably an engineer with experience of such appliances) to check what voltages are where, and it should become quickly apparent what's wrong. You need to befriend an electrical handyman!! But then knowing what's wrong may still not fix the problem - there may be more expense searching for, purchasing and fitting parts (where available)

So why are the background heating elements not coming on?
My thoughts on possible reasons:
The off-peak supply is not getting to the heaters that don't work.
The RXPW4 controller is preventing, or not enabling, background heating because of the status it has set on the pilot wire (of the heaters that are not working)
Something within the controller of each heater has broken (but why 3 heaters all 'faulty'?)
The fusible links for the background heater have blown (but as above)

So one last suggestion - could you focus on the RXPW4 controller, and check if there is anything you are supposed to set it to to enable background heating. Presumably you have instructions for that?

Thank you for your perseverance too!

 

[Agaxyz]

It seems you are doing all the right things with the controls.
Yes the idea is to have background turned up enough to give you the heat you need through most of the day, and as you say, you probably don't need much, if any, comfort heating at all. Since the elements are not being switched on by the controllers, in the ones that don't work, for some reason, it really doesn't matter how you leave them set at the moment!

The frustrating thing is that what you really need at this point is a competent engineer with a multimeter (preferably an engineer with experience of such appliances) to check what voltages are where, and it should become quickly apparent what's wrong. You need to befriend an electrical handyman!! But then knowing what's wrong may still not fix the problem - there may be more expense searching for, purchasing and fitting parts (where available)

So why are the background heating elements not coming on?
My thoughts on possible reasons:
The off-peak supply is not getting to the heaters that don't work.
The RXPW4 controller is preventing, or not enabling, background heating because of the status it has set on the pilot wire (of the heaters that are not working)
Something within the controller of each heater has broken (but why 3 heaters all 'faulty'?)
The fusible links for the background heater have blown (but as above)

So one last suggestion - could you focus on the RXPW4 controller, and check if there is anything you are supposed to set it to to enable background heating. Presumably you have instructions for that?

Thank you for your perseverance too!

Thank you again very much. Yes I have the instruction for this controller - again old type but will do. Will read it, yet the two questions/comments I have remain:

A. somehow 1st heater and the water heater , which both were also connected to the controller still works now. Very likely they both were in a different/separate zone, and only other zones where the other heaters are might have been affected by "something" connected to that controller. At least this is my understanding of this situation.

B. When I turn this control on, will it automatically go to the old set up, or will I have to set it up from the beginning? The previous tenant told me that the zones were automatically set up already.

And one more question in relation to it "...and check if there is anything you are supposed to set it to to enable background heating..." if there will be something I would need to set up, would it mean that I always would have to have this controller on? There are flats here where they do not use it either and the heater are working. Maybe once set up, it has to be somehow properly "un set up/disconnected/disabled" rather than by switching the power on the wall, this is what I did as someone told to just do it this way.... what a mess, but we will get there. Rather scared to turn this controller on as again worrying about this working heater and the hot water heater - hopefully they are not going to be affected.

Once I have some more news in relation to it, I will post it - it might not be tomorrow as I will try to talk to one person who uses that panel and should know more, not sure when this person would be available though. Have a good evening

 

[Avo Mk8]

Thank you again very much. Yes I have the instruction for this controller - again old type but will do. Will read it, yet the two questions/comments I have remain:

A. somehow 1st heater and the water heater , which both were also connected to the controller still works now. Very likely they both were in a different/separate zone, and only other zones where the other heaters are might have been affected by "something" connected to that controller. At least this is my understanding of this situation.

B. When I turn this control on, will it automatically go to the old set up, or will I have to set it up from the beginning? The previous tenant told me that the zones were automatically set up already.

And one more question in relation to it "...and check if there is anything you are supposed to set it to to enable background heating..." if there will be something I would need to set up, would it mean that I always would have to have this controller on? There are flats here where they do not use it either and the heater are working. Maybe once set up, it has to be somehow properly "un set up/disconnected/disabled" rather than by switching the power on the wall, this is what I did as someone told to just do it this way.... what a mess, but we will get there. Rather scared to turn this controller on as again worrying about this working heater and the hot water heater - hopefully they are not going to be affected.

Once I have some more news in relation to it, I will post it - it might not be tomorrow as I will try to talk to one person who uses that panel and should know more, not sure when this person would be available though. Have a good evening

Thank you for this.

To answer A: if the water heater is connected via the Dimplex "Pilot Wire Interface Unit" (see my ramblings at the end below) to the controller, and the controller is switched off, the water heater will be permanently 'on'.
I'm beginning to understand that if the wall controller is 'off', and hence the pilot wire is 'off', then the heaters should just work from their buttons, but with none of the additional features of the wall control. However that's not completely borne out by the wall controler instructions below.

To answer B: If you turn the controller 'on', it will remember and revert to the original settings used by the previous occupants, according to the instructions.

Re the "one more question", I think I have established that your heaters ought to work with the controller in the 'off' state.
So don't worry about that, just leave the controller 'off' for the time being.
The curious thing is though, that the instructions for the controller do say that the controller should be set to 'comfort' (the sort of sun symbol) for the heaters background mode to work. see the trouble shooting part of the guide here:

https://www.dimplex.co.uk/sites/default/files/assets//RXMBS4_RXPW4_Operating_Instructions_Issue_0.pdf

So you might summon up your courage and set the wall controller to 'comfort' and see if anything changes overnight. If not, return it to 'off'!

To continue the fault finding game (!), I recommend you do a check of the off-peak fuseboard feeding the radiators:
You probably have two 'fuse boards', one for the normal power to sockets and lights etc, and one for the off-peak heaters. You should be able to tell which is which from the little labels by the fuses (MCB's). I would like you to make sure all the heater switches/'fuses' are "ON" !
If you have difficulty identifying what is what, a photo attached to your next post would help.

On the subject of your working hot water tank, I have been looking at the information on the Dimplex RXPWIF "Pilot Wire Interface Unit" that would be the connection between your wall controller and the tank, here:

https://www.dimplex.co.uk/sites/default/files/assets//RXPWIF_Instructions_Issue_004.pdf

This says that if the controller is switched 'off', the water heater will be on all the time. Which will be why you have hot water.
It would be useful to check if you can see a RXPWIF box on the wall wired to the immersion. If not, maybe the immersion heater is just wired directly to the off-peak supply.

Going back to your mention of the three switches on the wall for each heater (Which are presumably for day-rate power, night-rate power, and pilot wire for the controller). Is it the case that all three switches are on for all heaters (apart from the faulty/noisy one)? Has the first heater that's working properly got all 3 switches on?

Finally, can I ask if you are owner or tenant? If the latter, surely the Landlord has responsibility for sorting this out?

 

[Agaxyz]

Thank you for this.

To answer A: if the water heater is connected via the Dimplex "Pilot Wire Interface Unit" (see my ramblings at the end below) to the controller, and the controller is switched off, the water heater will be permanently 'on'.
I'm beginning to understand that if the wall controller is 'off', and hence the pilot wire is 'off', then the heaters should just work from their buttons, but with none of the additional features of the wall control. However that's not completely borne out by the wall controler instructions below.

To answer B: If you turn the controller 'on', it will remember and revert to the original settings used by the previous occupants, according to the instructions.

Re the "one more question", I think I have established that your heaters ought to work with the controller in the 'off' state.
So don't worry about that, just leave the controller 'off' for the time being.
The curious thing is though, that the instructions for the controller do say that the controller should be set to 'comfort' (the sort of sun symbol) for the heaters background mode to work. see the trouble shooting part of the guide here:

https://www.dimplex.co.uk/sites/default/files/assets//RXMBS4_RXPW4_Operating_Instructions_Issue_0.pdf

So you might summon up your courage and set the wall controller to 'comfort' and see if anything changes overnight. If not, return it to 'off'!

To continue the fault finding game (!), I recommend you do a check of the off-peak fuseboard feeding the radiators:
You probably have two 'fuse boards', one for the normal power to sockets and lights etc, and one for the off-peak heaters. You should be able to tell which is which from the little labels by the fuses (MCB's). I would like you to make sure all the heater switches/'fuses' are "ON" !
If you have difficulty identifying what is what, a photo attached to your next post would help.

On the subject of your working hot water tank, I have been looking at the information on the Dimplex RXPWIF "Pilot Wire Interface Unit" that would be the connection between your wall controller and the tank, here:

https://www.dimplex.co.uk/sites/default/files/assets//RXPWIF_Instructions_Issue_004.pdf

This says that if the controller is switched 'off', the water heater will be on all the time. Which will be why you have hot water.
It would be useful to check if you can see a RXPWIF box on the wall wired to the immersion. If not, maybe the immersion heater is just wired directly to the off-peak supply.

Going back to your mention of the three switches on the wall for each heater (Which are presumably for day-rate power, night-rate power, and pilot wire for the controller). Is it the case that all three switches are on for all heaters (apart from the faulty/noisy one)? Has the first heater that's working properly got all 3 switches on?

Finally, can I ask if you are owner or tenant? If the latter, surely the Landlord has responsibility for sorting this out?

Hello, could not reply earlier, apologies, busy day.

Thank you for all the links/documents.

Will respond from the end: tenant or owner? Well, there is the 3rd option: I'm both as it is shared ownership The landlord/managing agency would not help in terms of the heaters...

Yes, for the heater that works properly, plus for all the heaters that kind of work, all 3 switches are on.

There is RXPWIF box on one side of the wall (inside the cabinet where the water tank is) and on the other side there are those two switches as per the photo. When the night rates comes on, the switch on the left on the photo is red. I've never used the switch for the immersion, as for me enough water is heated throughout the night (though I know the people who used to live here before did use the immersion as well).

The photos of the fuse boards are also here - from my point of they they all look fine.

In re to "...The curious thing is though, that the instructions for the controller do say that the controller should be set to 'comfort' (the sort of sun symbol) for the heaters background mode to work. see the trouble shooting part of the guide here:.." I had a look at it, and not sure I understand properly what would the comfort mode between 8AM & 10AM – 3PM & 9PM mean? Would it meant that option 1: the heat stored overnight is only shared/given away by the heater between 8AM & 10AM – 3PM & 9PM. Or option 2, does it meant the heaters would use the day heating (at the day rate) as well during those periods to allow the use of the night storage? Or maybe there is the 3rd option?

Also about turning this controller on - I would have to set up the day and time myself when I decide to turn this on (silly questions but better to check) probably yes?

That is all from me

 

[Avo Mk8]

Sorry I haven't replied for a while.
Thank you for the pics, which indicate there is nothing untoward with the power arrangements.

I'm afraid, basically, I know nothing about the controller!
If you decided to try it, I would recommend setting the clock to the correct time.
But I'm inclined to believe the background heating should work with the controller switched off - something you might check with neighbours if you haven't already. If that is the case, I would leave the controller 'off'.

So it seems there's no explanation for heaters not working, other than some failure(s) inside.

As far a water heating is concerned, it seems the main heater is directly on the night rate supply, and although there is the RXPWIF switch there, it's not actively timing the water heater. That's not a problem.

So I fear I don't have any other suggestions. It sems each non-working heater needs to be opened up and fault finding carried out.
The problem here is that an engineer's call-out charge, hourly rate, and the likely cost of spares (and finding them), it likely to be considerable. For this reason you may find you will only be able to get quotes for replacing the heaters, as many may consider the 'repair' option is so unpredictable, they won't want to risk losing money!
This is where a DIY repair (by someone competent) is probably the only economically viable option!

 

[Agaxyz]

Sorry I haven't replied for a while.
Thank you for the pics, which indicate there is nothing untoward with the power arrangements.

I'm afraid, basically, I know nothing about the controller!
If you decided to try it, I would recommend setting the clock to the correct time.
But I'm inclined to believe the background heating should work with the controller switched off - something you might check with neighbours if you haven't already. If that is the case, I would leave the controller 'off'.

So it seems there's no explanation for heaters not working, other than some failure(s) inside.

As far a water heating is concerned, it seems the main heater is directly on the night rate supply, and although there is the RXPWIF switch there, it's not actively timing the water heater. That's not a problem.

So I fear I don't have any other suggestions. It sems each non-working heater needs to be opened up and fault finding carried out.
The problem here is that an engineer's call-out charge, hourly rate, and the likely cost of spares (and finding them), it likely to be considerable. For this reason you may find you will only be able to get quotes for replacing the heaters, as many may consider the 'repair' option is so unpredictable, they won't want to risk losing money!
This is where a DIY repair (by someone competent) is probably the only economically viable option!

Hello and thank you for all your help, advice and input in general - everything has been very helpful. I will try to sort this out somehow Merry Christmas or Happy Holiday season

 

[Agaxyz]

Sorry I haven't replied for a while.
Thank you for the pics, which indicate there is nothing untoward with the power arrangements.

I'm afraid, basically, I know nothing about the controller!
If you decided to try it, I would recommend setting the clock to the correct time.
But I'm inclined to believe the background heating should work with the controller switched off - something you might check with neighbours if you haven't already. If that is the case, I would leave the controller 'off'.

So it seems there's no explanation for heaters not working, other than some failure(s) inside.

As far a water heating is concerned, it seems the main heater is directly on the night rate supply, and although there is the RXPWIF switch there, it's not actively timing the water heater. That's not a problem.

So I fear I don't have any other suggestions. It sems each non-working heater needs to be opened up and fault finding carried out.
The problem here is that an engineer's call-out charge, hourly rate, and the likely cost of spares (and finding them), it likely to be considerable. For this reason you may find you will only be able to get quotes for replacing the heaters, as many may consider the 'repair' option is so unpredictable, they won't want to risk losing money!
This is where a DIY repair (by someone competent) is probably the only economically viable option!

Hello again, I have contacted the electrician to come and have the look at those heaters, finally he might come and before the visit the sent me the message - part of the message is below:

"...On my visit as well as discussing the work you require I will also need to look at the existing fuse board. Two other things again we need to check is your water and gas (or oil) bonding. With them being metallic pipes rising from the ground these can carry an earth potential, we need to ensure they have the necessary earthing cables and clamps and run back to the Main Earthing Terminal, again this should be at the fuse board. Sometimes it is not always possible to confirm these 100% of the time but will give us a good idea of what's going on. With the need of having to look at these items (Fuse Board, Water & Gas) it would be good if anything stored in the same cupboards as them were removed so we can get the best view possible...."

I understand the fuse board needs to be checked but the water and gas pipes ( I do not have gas anyway)? Ok I'm not an electrician so is it a standard thing? The electrician wants to come have a look, assess first and next will give me a quote. I thought that when he comes he at once would be able to at least check and if necessary replace the fuses but the switches next to each heater, it seems like a small job (if that needs to be done). I also offered to buy some parts still available on ebay - you had suggested but have not beard about it. It would be more efficient if "simple" things which might casue the issue could be fixed at once, wouldn't it? I am just worried by this email that it already sounds like a huge job...

 

[Avo Mk8]

Hello again, I have contacted the electrician to come and have the look at those heaters, finally he might come and before the visit the sent me the message - part of the message is below:

"...On my visit as well as discussing the work you require I will also need to look at the existing fuse board. Two other things again we need to check is your water and gas (or oil) bonding. With them being metallic pipes rising from the ground these can carry an earth potential, we need to ensure they have the necessary earthing cables and clamps and run back to the Main Earthing Terminal, again this should be at the fuse board. Sometimes it is not always possible to confirm these 100% of the time but will give us a good idea of what's going on. With the need of having to look at these items (Fuse Board, Water & Gas) it would be good if anything stored in the same cupboards as them were removed so we can get the best view possible...."

I understand the fuse board needs to be checked but the water and gas pipes ( I do not have gas anyway)? Ok I'm not an electrician so is it a standard thing? The electrician wants to come have a look, assess first and next will give me a quote. I thought that when he comes he at once would be able to at least check and if necessary replace the fuses but the switches next to each heater, it seems like a small job (if that needs to be done). I also offered to buy some parts still available on ebay - you had suggested but have not beard about it. It would be more efficient if "simple" things which might casue the issue could be fixed at once, wouldn't it? I am just worried by this email that it already sounds like a huge job...

The electrician will need access to the fuseboard, so asking if things can be cleared out of the way is good. However it sounds to me as if the electrician is wanting to look at earth bonding arrangements in your electrical installation, which in my humble opinion is nothing to do with determining why your heaters don't work (and it will not give him "a good idea of what's going on" with regard to the heaters.! It looks suspiciously as if he is looking for further, perhaps more remunerative, work, or an excuse to conduct an Electrical Installation Condition Report (EICR). If yours is a rented property (sorry - can't remember!) the Landord is responsible for having that done, not you.
You might tactufully sugest he is welcome to review water pipe bonding if he must, but only after he has diagnosed, and fixed, your heaters.
I don't think it is a good idea to buy random spare parts in advance of an electrician looking for the fault.
Just be a bit wary and reiterate that you want a diagnosis of why the heaters do not work, not advice, or a report, on the condition of your electrical installation.

 

[AlexFullerton]

You might have to call an electrician for this so they can test the on peak and off peak flow for you.

 

[Agaxyz]

Hello,

A bit of an “update”.

A couple of months ago an electrician came to look at those heaters which did not store the heat overnight. It was one brave electrician who did not have much experience with those heaters but was willing to help, all other electricians to whom I had talked to, said it was not worth it to look at those heaters anymore as they were discontinued.

Ok, so the electrician took the heaters all apart to check. It seems the CREDA DIMPLEX STORAGE HEATER CHARGE CONTROL MODULEs were not working in them. So he also took apart that one heater that used to work properly, and from that working heater he took that control module out and put it in the other heaters (those which did not store the heat overnight) to check if it would be working there and if it would make a difference – I am not an electrician, so I cannot specifically say what he did, but he did connect some cables to check the day electricity flow, including the night electricity flow E7 and it seemed it was flowing/working (he was able to check this night E7 electricity flow somehow during the day when he was here - apologies I know my description of what he did is rather “not precise/not professional” yet again I do not know much about the electricity). Anyway, once he checked those other heaters with that control module from that heater which worked he decided that that control module would need to be changed in all of them…(=needed to be changed in those ones which did not store the heat overnight to make them store the heat overnight). Ok.

At the end of the visit, once everything was checked, he put all heaters back to how they were, it also means that he put back the control module which was working last winter into the heater that used to work last winter. It was summer, the heaters were turned off, so I could not check if it was working again as it used it, it was too hot outside as well. Now it is getting colder, I turned that heater that used to work on, but the night storage heat stopped working… I could not believe it….So it does not store the heat overnight = it is cold in the morning, so the background mode is not working (it does not store the heat overnight), but the comfort zone is working.

It seems to have the same problem like with the other heaters. But what happened? It used to work before, and the electrician put the correct control module back in? Could you please advise? Would you have any idea how to make at last this one heater work again? As far as I know/read about those heaters the explanations might be:

• already mentioned: the control module also stopped working (but is this possible that something like this could happen just because he took it out and put it back in)?
• perhaps it is bad connection as he was disconnecting and connecting the parts heater?
• perhaps it is the thermostat (it seemed a little brown when he opened the cover, as the heater was used a lot)?
• Is it possible that I should only need to change the fuse which is next to the “off peak” switch on the wall to make that heater that used to work, work again?
• Any other idea why this one heater is not storing the heat overnight either now? Plus, which of the 4 ideas I mentioned is the most probable?

Someone, earlier in this thread mentioned “….The fusible links for the background heater have blown …” I was looking on the internet for those fusible links but can not sure how they look?

I think what I would like is the list of parts I should buy so when I call this electrician he can check and replace at once what needs to be replaced. The winter is coming, and it would be necessary to have 1-2 of those heaters working… In advance thank you for any advice.

 

[Avo Mk8]

I've been looking at availability of parts, and it seems that's considerably worse now than it was a year ago. There have been no spares available from Dimplex for years as you may know. I could not see any of the spares you need on eBay now, and one charge controller I see that had been for sale in the past went for £150!
Some of the electronic components inside your heaters, such as electrolytic capacitors, have probably reached their end of life, and the reliability of the assemblies may be so impaired that repair of your heaters with secondhand parts may not last long. In fact I think your enterprising electrician has demonstrated that concept - that the remaining parts are now so fragile that they may fail!

I think you have to accept the fact that these heaters are beyond economic repair. Sorry.

 

[Agaxyz]

I think I might give it one more try. Seem a bit bizarre that those heaters are working in the other flats (not ideally and not all of them but still ...) and all of mine do not store the heat overnight ( plus the one which is constantly buzzing when turned on is totally out of order).. However, can someone please recommend some good heaters with the night storage option as well - just in case I really have to get one...

 

[freddo]

The general design and the PCBs in these are terrible and have a very short life. The components are underrated and the PCBs are mounted in a hot location, making the problem worse. They are often brown from the heat. They can sometimes be repaired but if the board is burned it's game over.

These are rubbish heaters, you are better off replacing them with the newer Quantum heaters, the design is much improved, though care should be taken to set the parameters up correctly to prevent excessive electricity use.

 

[Avo Mk8]

I think I might give it one more try. Seem a bit bizarre that those heaters are working in the other flats (not ideally and not all of them but still ...) and all of mine do not store the heat overnight ( plus the one which is constantly buzzing when turned on is totally out of order)..

You could always see if these people can repair the modules in your radiators, if you can get the offending items removed safely:

Module pcb REPAIR SERVICE Storage heater Dimplex Duoheat 300n 330 400 N 87389B | eBay

Any Storage Heater. Brief Fault Symptoms. This is a Repair Service. Test and repair of your module/pcb Update for orders placed after 25/08/22. What you need to do. In the unlikely event of loss, our liability is limited to the cost of the repair service.

www.ebay.co.uk

I have no experience of this seller, though they seem to have good feedback, but I'm not recommending this as the complete solution to your heating issues!

 

[Agaxyz]

Thank you for the suggestion

 

[Agaxyz]

Just a question, is it safe to take the module out and leave the heater without it for a week or so? - not sure how long the repairs will take.