Immersion Heater - PV electricity

[Duplada]

My first post here, though I have been reading this thread since I had my 3.84kw PV system installed last November. The reason for my post is to give those of you who are considering using your excess PV to power your immersion heater, insight into some of my experiences using manual switching and using a proportional device. After reading this thread from start to finish, when it originally had over 50 pages, it soon became apparent to me that a proportional solution was the way to go, because as far as I could see, all the other none proportional solutions had the possibility of importing more electricity than you were trying to save.

Since I first had my PV system installed I have monitored my PV generation with a SunnyBeam, my true house load with a clamp sensor on a Current Cost ENVIR Monitor (via a /Henley Block) and also my real time energy import with an Optismart reader on another Current Cost ENVIR monitor. These days, the data from these devices is output and recorded in an SQL database before being uploaded to one of the PV statistics sites. This setup allows me to see the true house load on one monitor and to see instantly if I am importing or exporting on the Optismart monitor. The Optismart monitor counts the pulses generated from the Electricity meter and is very accurate indeed, it shows zero when you are exporting. When you are importing the Optismart shows your true import and the difference between the house load monitor and the Optismart is your real time generation, which of course can be confirmed on the Sunnybeam generation monitor.

Finally to the reason for telling you about all these monitors, I work from home and with them sat on my desk it was difficult not look at them constantly. Monitoring my ever changing power status this way, enabled me to manually switch on washing machines, tumble dryers, dishwashers etc in sequence when sufficient power was available. I managed up to the end of February this year and was using about 70% of the power I generated. When March arrived with numerous sunny days (remember those) resulting in daily generation in excess of 22KW it was very clear that I could not mop up all the available excess power. By lunch time I had done two loads of washing two loads of tumble drying and had run the dishwasher and was now exporting again, with nothing left to run. My PV panels are at an inclination of 22 degrees so I do not generate over 3KW until the end of March. Therefore firing up the Immersion heater (3KW) would have meant also importing prior to this date, so up until the end of March the Immersion heater was not part of the manual load switching. Even when I could fire up the Immersion heater without importing I was forever having to switch it off again as it clouded over. In fact managing all this excess power was becoming a full time job and it was driving me nuts.

I therefore decided for my sanity that I had to get hold of one of these proportional controllers that dumped any excess into the Immersion, so that I could mop up any excess over my base load. If you have the means of monitoring your consumption and generation in real time like I have, you will have noticed that very often in particular on cloudy days, or early and late in the evenings, there can be a continuous small excess of say 300 to 500 watts, it is more or less impossible to mop up this excess without a proportional controller, and it adds up to quite a lot of export over an entire day.

Since I am not a electronics wizard building my own unit was out of the question for me. I managed to get hold of a kit manufactured by Echase a regular poster here. At the time (April 2012) he was handing his design over to a company for commercial production and had a few kits still for sale. To get the kit I had to sign a non-disclosure agreement, so I can’t talk about how much it cost its design etc. Though I don’t think Echase will mind me telling you that it is a very professional unit and works very well indeed. As I understand it, the same commercial unit that I have, can be purchased from Engesa with a PV system, but it is going to be available to purchase on its own, if enough people enquire about it. I think its commercial name is Solar24. I would also like to point out that I have no connection with either Echase or Engesa,

The unit connects between your consumer unit and your immersion circuit, there is no configuration whatsoever, you switch it on and it just works.

I have had the unit installed and operational now for over two and a half months and the unit is mopping up around 90% of my excess power. The unit exports a very small amount of power and never imports when a load changes (I can see this on my OptiSmart). It typically sorts out the new export value in about a second or two, if the load changes (kettle switched on) or a cloud appears to lower generation, but it never imports which is quite remarkable. Since the beginning of May when I completed the unit, my GAS central water heating has been off. I have only had to heat the water twice during this period, due to consecutive days of very poor weather. I have very detailed records of my GAS usage and during the two and half months I have had the unit in operation I have saved about £25 in GAS. I am quite satisfied with this; it will obviously be lower in winter but nevertheless a good saving.

There are one are two things I can point out to help you maximize the amount of excess power you can mop up. My hot water tank is a big one nearly 2 meters tall and holds 240 liters. However, my Immersion is only just under a meter in length. Therefore, I am only heating half the tank, this takes about 7KW to heat from cold but typically takes less on a daily basis as the water is not cold. To maximize the amount of water I can heat in my tank, and the excess export I can use, I am using a low voltage pump and two thermostats to circulate the water in the tank, to automate the process of heating a full tank.

On really sunny days (joke) my system can generate about 29KW so even after heating my big tank of water and running every white goods device to hand, I can still end up exporting 6 to 9KW. The real benefit though is I no longer have to think about the excess PV on most days, my proportion device just takes care of heating the water which is lowering the amount I spend on GAS. The other big asset is that I am no longer rushing around the house performing sequential domestic appliance management and have got my life back.

If you have managed to read this far you deserve a medal, and I promise not to post again. Though my advice is, if you want to have an easy life, and save money, then invest in a proportional device.

regards

 

[Duplada]

My first post here, though I have been reading this thread since I had my 3.84kw PV system installed last November. The reason for my post is to give those of you who are considering using your excess PV to power your immersion heater, insight into some of my experiences using manual switching and using a proportional device. After reading this thread from start to finish, when it originally had over 50 pages, it soon became apparent to me that a proportional solution was the way to go, because as far as I could see, all the other none proportional solutions had the possibility of importing more electricity than you were trying to save.

Since I first had my PV system installed I have monitored my PV generation with a SunnyBeam, my true house load with a clamp sensor on a Current Cost ENVIR Monitor (via a /Henley Block) and also my real time energy import with an Optismart reader on another Current Cost ENVIR monitor. These days, the data from these devices is output and recorded into an SQL database before being uploaded to one of the PV statistics sites. This 3 monitor setup allows me to see the true house load on one monitor and to see instantly if I am importing or exporting on the Optismart monitor. The Optismart monitor counts the pulses generated from the Electricity meter and is very accurate indeed, it shows zero when you are exporting. When you are importing the Optismart shows your true import and the difference between the house load monitor and the Optismart is your real time generation, which of course can be confirmed on the Sunnybeam generation monitor.

Finally to the reason for telling you about all these monitors, I work from home and with them sat on my desk it was difficult not look at them constantly. Monitoring my ever changing power status this way, enabled me to manually switch on washing machines, tumble dryers, dishwashers etc in sequence when sufficient power was available. I managed up to the end of February this year and was using about 70% of the power I generated. When March arrived with numerous sunny days (remember those) resulting in daily generation in excess of 22KW it was very clear that I could not mop up all the available excess power. By lunch time I had done two loads of washing two loads of tumble drying and had run the dishwasher and was now exporting again, with nothing left to run. My PV panels are at an inclination of 22 degrees so I do not generate over 3KW until the end of March. Therefore, firing up the Immersion heater (3KW) would have meant also importing prior to this date, so up until the end of March the Immersion heater was not part of the manual load switching. Even when I could fire up the Immersion heater from the end of March without importing, I was forever having to switch it off again as it clouded over. In fact managing all this excess power was becoming a full time job and it was driving me nuts.

I therefore decided for my sanity that I had to get hold of one of these proportional controllers that dumped any excess into the Immersion, so that I could mop up any excess over my base load. If you have the means of monitoring your consumption and generation in real time like I have, you will have noticed that very often in particular on cloudy days, in winter months, or early and late in the day in summer, there can be a continuous small export excess of say 300 to 500 watts over base load. It is more or less impossible to mop up this excess without a proportional controller, and it adds up to quite a lot of export over an entire day.

Since I am not a electronics wizard building my own unit was out of the question for me. I managed to get hold of a kit manufactured by Echase a regular poster here. At the time (April 2012) he was handing his design over to a company for commercial production and had a few kits still for sale. To get the kit I had to sign a non-disclosure agreement, so I can’t talk about how much it cost its design etc. Though I don’t think Echase will mind me telling you that it is a small very professionally designed unit that works very well indeed. As I understand it, the same commercial unit that I have, can be purchased from Engensa with a PV system, but it is going to be available to purchase on its own, if enough people enquire about it. I think its commercial name is Solar24. I would also like to point out that I have no connection with either Echase or Engensa.

The unit connects between your consumer unit and your immersion circuit, there is no configuration whatsoever, you switch it on and it just works.

I have had the unit installed and operational now for over two and a half months and the unit is mopping up around 80% of my excess power. The unit exports a very small amount of power and never imports when a load changes (I can see this on my OptiSmart). It typically sorts out the new export value in about a second, if the load changes (kettle switched on) or a cloud appears to lower generation, but it never imports which is quite remarkable. Since the beginning of May when I completed the unit, my GAS central water heating has been off. I have only had to heat the water twice during this period, due to consecutive days of very poor weather and kids home from University wanting consecutive baths. I have very detailed records of my GAS usage and during the two and half months I have had the unit in operation I have saved about £25 in GAS. I am quite satisfied with this; it will obviously be lower in winter but nevertheless a good saving.

There are one are two things I can point out to help you maximize the amount of excess power you can mop up. My hot water tank is a big one nearly 2 meters tall and holds 240 liters. However, my Immersion is only just under a meter in length. Therefore, I am only heating about half the tank, this takes about 7KW to heat from cold, but typically takes less (4-5KW) on a daily basis as the water is not cold. To maximize the amount of water I can heat in my tank, and the excess export I can use, I am using a low voltage pump and two thermostats to circulate the water in the tank, to automate the process of heating a full tank. You have to think about when you use the hot water also, having a bath late at night may well leave you without much in the morning if the next day is cloudy.

On really sunny days in summer (joke) my system can generate about 29KW so even after heating my big tank of water and running every white goods device to hand, I can still end up exporting 6 to 9KW, however this is the exception rather than the norm. So depending on the size of your hot water cylinder, your base house load, and whether or not you are at home in the day to run other devices, will depend on how much you can actually save. The real benefit though for me, is I no longer have to think about how to use the excess PV generation on most days, as my proportional device just mops up all the excess heating the water and lowering the amount I spend on GAS. The other big asset is that I am no longer rushing around the house performing sequential domestic appliance management and have got my life back.

If you have managed to read this far you deserve a medal, and I promise not to post again. In conclusion, if you want to maximize the use of your excess PV generation then get yourself a proportional PV controller as in my experience they really do work very well.

regards

 

[Duplada]

My first post here, though I have been reading this thread since I had my 3.84kw PV system installed last November. The reason for my post is to give those of you who are considering using your excess PV to power your immersion heater, insight into some of my experiences using manual switching and using a proportional device. After reading this thread from start to finish, when it originally had over 50 pages, it soon became apparent to me that a proportional solution was the way to go, because as far as I could see, all the other none proportional solutions had the possibility of importing more electricity than you were trying to save.

Since I first had my PV system installed I have monitored my PV generation with a SunnyBeam, my true house load with a clamp sensor on a Current Cost ENVIR Monitor (via a /Henley Block) and also my real time energy import with an Optismart reader on another Current Cost ENVIR monitor. These days, the data from these devices is output and recorded into an SQL database before being uploaded to one of the PV statistics sites. This 3 monitor setup allows me to see the true house load on one monitor and to see instantly if I am importing or exporting on the Optismart monitor. The Optismart monitor counts the pulses generated from the Electricity meter and is very accurate indeed, it shows zero when you are exporting. When you are importing the Optismart shows your true import and the difference between the house load monitor and the Optismart is your real time generation, which of course can be confirmed on the Sunnybeam generation monitor.

Finally to the reason for telling you about all these monitors, I work from home and with them sat on my desk it was difficult not look at them constantly. Monitoring my ever changing power status this way, enabled me to manually switch on washing machines, tumble dryers, dishwashers etc in sequence when sufficient power was available. I managed up to the end of February this year and was using about 70% of the power I generated. When March arrived with numerous sunny days (remember those) resulting in daily generation in excess of 22KW it was very clear that I could not mop up all the available excess power. By lunch time I had done two loads of washing two loads of tumble drying and had run the dishwasher and was now exporting again, with nothing left to run. My PV panels are at an inclination of 22 degrees so I do not generate over 3KW until the end of March. Therefore, firing up the Immersion heater (3KW) would have meant also importing prior to this date, so up until the end of March the Immersion heater was not part of the manual load switching. Even when I could fire up the Immersion heater from the end of March without importing, I was forever having to switch it off again as it clouded over. In fact managing all this excess power was becoming a full time job and it was driving me nuts.

I therefore decided for my sanity that I had to get hold of one of these proportional controllers that dumped any excess into the Immersion, so that I could mop up any excess over my base load. If you have the means of monitoring your consumption and generation in real time like I have, you will have noticed that very often in particular on cloudy days, in winter months, or early and late in the day in summer, there can be a continuous small export excess of say 300 to 500 watts over base load. It is more or less impossible to mop up this excess without a proportional controller, and it adds up to quite a lot of export over an entire day.

Since I am not a electronics wizard building my own unit was out of the question for me. I managed to get hold of a kit manufactured by Echase a regular poster here. At the time (April 2012) he was handing his design over to a company for commercial production and had a few kits still for sale. To get the kit I had to sign a non-disclosure agreement, so I can’t talk about how much it cost its design etc. Though I don’t think Echase will mind me telling you that it is a small very professionally designed unit that works very well indeed. As I understand it, the same commercial unit that I have, can be purchased from Engensa with a PV system, but it is going to be available to purchase on its own, if enough people enquire about it. I think its commercial name is Solar24. I would also like to point out that I have no connection with either Echase or Engensa.

The unit connects between your consumer unit and your immersion circuit, there is no configuration whatsoever, you switch it on and it just works.

I have had the unit installed and operational now for over two and a half months and the unit is mopping up around 80% of my excess power. The unit exports a very small amount of power and never imports when a load changes (I can see this on my OptiSmart). It typically sorts out the new export value in about a second, if the load changes (kettle switched on) or a cloud appears to lower generation, but it never imports which is quite remarkable. Since the beginning of May when I completed the unit, my GAS central water heating has been off. I have only had to heat the water twice during this period, due to consecutive days of very poor weather and kids home from University wanting consecutive baths. I have very detailed records of my GAS usage and during the two and half months I have had the unit in operation I have saved about £25 in GAS. I am quite satisfied with this; it will obviously be lower in winter but nevertheless a good saving.

There are one are two things I can point out to help you maximize the amount of excess power you can mop up. My hot water tank is a big one nearly 2 meters tall and holds 240 liters. However, my Immersion is only just under a meter in length. Therefore, I am only heating about half the tank, this takes about 7KW to heat from cold, but typically takes less (4-5KW) on a daily basis as the water is not cold. To maximize the amount of water I can heat in my tank, and the excess export I can use, I am using a low voltage pump and two thermostats to circulate the water in the tank, to automate the process of heating a full tank. You have to think about when you use the hot water also, having a bath late at night may well leave you without much in the morning if the next day is cloudy.

On really sunny days in summer (joke) my system can generate about 29KW so even after heating my big tank of water and running every white goods device to hand, I can still end up exporting 6 to 9KW, however this is the exception rather than the norm. So depending on the size of your hot water cylinder, your base house load, and whether or not you are at home in the day to run other devices, will depend on how much you can actually save. The real benefit though for me, is I no longer have to think about how to use the excess PV generation on most days, as my proportional device just mops up all the excess heating the water and lowering the amount I spend on GAS. The other big asset is that I am no longer rushing around the house performing sequential domestic appliance management and have got my life back.

If you have managed to read this far you deserve a medal, and I promise not to post again. In conclusion, if you want to maximize the use of your excess PV generation then get yourself a proportional PV controller as they do really work very well.

regards

 

[JohnBoyZ]

Hey guys,

I need some electronics advice. I have the cheap ebay 3800w dimmer triac circuit mentioned earlier (inkFrog) that "dims" the power supplied to my immersion heater, the dimming is controlled using an AC potentionmeter (model: wth118-1a).

I now need to programmatically control the potentiometer. Aside from getting an SSR and redoing the circuit, etc., I have explored using a servo motor controlled via USB to turn the pot, but have discovered that 5v/100ma from USB isn't strong enough for the motor to turn the knob (plus very inaccurate) - I want to avoid external power supplies etc. Is it possible to instead send a 5v current down a USB directly (via some conversion circuit of some sort) to one of the terminals of the potentiometer and thus vary the resistance (i'm looking for the simplest solution possible). I am happy with a binary "high power" and "low power", i.e. 5v and 0v from usb. This would allow me to at least step the potentiometer/dimmer circuit one level up when solar pv generation is high.

Thanks.

Have you considered a Vactrol, (optocoupled LDR) there are various ones available, here is a link to the ones on the Farnell website VTL5C1 - EXCELITAS TECH - OPTOCOUPLER, SINGLE CHANNEL | Farnell United Kingdom

 

[Maurice Sauer]

Re: Immersion Heater - PV electricity.

I also installed an echase unit about five months ago and it seems to work very well and I have no reservations about reccommending this. So totaly agree with Duplada. There seem to be quite a few within this blog who wish to reinvent the wheel, but using approaches which don't readily meet the key criterion of heating water whilst minimising the possibility of drawing from the grid. I would welcome further info from Duplada about his pumping system, since I have similar issue of only heating a half tank - and don't wish to install a longer heater because of the possibility os snagging on the (central heating) heating coil.

cheers Mo

My first post here, though I have been reading this thread since I had my 3.84kw PV system installed last November. The reason for my post is to give those of you who are considering using your excess PV to power your immersion heater, insight into some of my experiences using manual switching and using a proportional device. After reading this thread from start to finish, when it originally had over 50 pages, it soon became apparent to me that a proportional solution was the way to go, because as far as I could see, all the other none proportional solutions had the possibility of importing more electricity than you were trying to save.

Since I first had my PV system installed I have monitored my PV generation with a SunnyBeam, my true house load with a clamp sensor on a Current Cost ENVIR Monitor (via a /Henley Block) and also my real time energy import with an Optismart reader on another Current Cost ENVIR monitor. These days, the data from these devices is output and recorded into an SQL database before being uploaded to one of the PV statistics sites. This 3 monitor setup allows me to see the true house load on one monitor and to see instantly if I am importing or exporting on the Optismart monitor. The Optismart monitor counts the pulses generated from the Electricity meter and is very accurate indeed, it shows zero when you are exporting. When you are importing the Optismart shows your true import and the difference between the house load monitor and the Optismart is your real time generation, which of course can be confirmed on the Sunnybeam generation monitor.

Finally to the reason for telling you about all these monitors, I work from home and with them sat on my desk it was difficult not look at them constantly. Monitoring my ever changing power status this way, enabled me to manually switch on washing machines, tumble dryers, dishwashers etc in sequence when sufficient power was available. I managed up to the end of February this year and was using about 70% of the power I generated. When March arrived with numerous sunny days (remember those) resulting in daily generation in excess of 22KW it was very clear that I could not mop up all the available excess power. By lunch time I had done two loads of washing two loads of tumble drying and had run the dishwasher and was now exporting again, with nothing left to run. My PV panels are at an inclination of 22 degrees so I do not generate over 3KW until the end of March. Therefore, firing up the Immersion heater (3KW) would have meant also importing prior to this date, so up until the end of March the Immersion heater was not part of the manual load switching. Even when I could fire up the Immersion heater from the end of March without importing, I was forever having to switch it off again as it clouded over. In fact managing all this excess power was becoming a full time job and it was driving me nuts.

I therefore decided for my sanity that I had to get hold of one of these proportional controllers that dumped any excess into the Immersion, so that I could mop up any excess over my base load. If you have the means of monitoring your consumption and generation in real time like I have, you will have noticed that very often in particular on cloudy days, in winter months, or early and late in the day in summer, there can be a continuous small export excess of say 300 to 500 watts over base load. It is more or less impossible to mop up this excess without a proportional controller, and it adds up to quite a lot of export over an entire day.

Since I am not a electronics wizard building my own unit was out of the question for me. I managed to get hold of a kit manufactured by Echase a regular poster here. At the time (April 2012) he was handing his design over to a company for commercial production and had a few kits still for sale. To get the kit I had to sign a non-disclosure agreement, so I can’t talk about how much it cost its design etc. Though I don’t think Echase will mind me telling you that it is a small very professionally designed unit that works very well indeed. As I understand it, the same commercial unit that I have, can be purchased from Engensa with a PV system, but it is going to be available to purchase on its own, if enough people enquire about it. I think its commercial name is Solar24. I would also like to point out that I have no connection with either Echase or Engensa.

The unit connects between your consumer unit and your immersion circuit, there is no configuration whatsoever, you switch it on and it just works.

I have had the unit installed and operational now for over two and a half months and the unit is mopping up around 80% of my excess power. The unit exports a very small amount of power and never imports when a load changes (I can see this on my OptiSmart). It typically sorts out the new export value in about a second, if the load changes (kettle switched on) or a cloud appears to lower generation, but it never imports which is quite remarkable. Since the beginning of May when I completed the unit, my GAS central water heating has been off. I have only had to heat the water twice during this period, due to consecutive days of very poor weather and kids home from University wanting consecutive baths. I have very detailed records of my GAS usage and during the two and half months I have had the unit in operation I have saved about £25 in GAS. I am quite satisfied with this; it will obviously be lower in winter but nevertheless a good saving.

There are one are two things I can point out to help you maximize the amount of excess power you can mop up. My hot water tank is a big one nearly 2 meters tall and holds 240 liters. However, my Immersion is only just under a meter in length. Therefore, I am only heating about half the tank, this takes about 7KW to heat from cold, but typically takes less (4-5KW) on a daily basis as the water is not cold. To maximize the amount of water I can heat in my tank, and the excess export I can use, I am using a low voltage pump and two thermostats to circulate the water in the tank, to automate the process of heating a full tank. You have to think about when you use the hot water also, having a bath late at night may well leave you without much in the morning if the next day is cloudy.

On really sunny days in summer (joke) my system can generate about 29KW so even after heating my big tank of water and running every white goods device to hand, I can still end up exporting 6 to 9KW, however this is the exception rather than the norm. So depending on the size of your hot water cylinder, your base house load, and whether or not you are at home in the day to run other devices, will depend on how much you can actually save. The real benefit though for me, is I no longer have to think about how to use the excess PV generation on most days, as my proportional device just mops up all the excess heating the water and lowering the amount I spend on GAS. The other big asset is that I am no longer rushing around the house performing sequential domestic appliance management and have got my life back.

If you have managed to read this far you deserve a medal, and I promise not to post again. In conclusion, if you want to maximize the use of your excess PV generation then get yourself a proportional PV controller as they do really work very well.

regards

 

[echase]

Glad the units are working well.

Some users have recommended this pump
DC 12V Electric Centrifugal Water Pump 103 GPH (P-38I) | eBay Search eBay for P-38I pump if the link does not work. But it’s 10 times the flow needed so needs throttling or running for short periods. Smaller pumps that have reliable pipe connections are not easy to find.

To ensure you get 60C at the top it's best to add a thermostat 2/3 to 3/4 up the cylinder to turn the pump off when temperature drops below say 55C. Remember the Legionella problem if heating less than 55C.

Mine is a special and expensive brushless variant of this 12V diaphragm pump http://www.charlesausten.com/Files/charlesaustenpumps/pdfs/88576.pdf The standard 12V non brushless version is reasonably priced but hard to buy one off. It’s flow rate is about right for this application.

 

[CBR600]

Hello echase

Is it possible to buy your unit from you or is it just through Engensa?

Many thanks

 

[pmcalli]

Hello echase

Is it possible to buy your unit from you or is it just through Engensa?

Many thanks

I have just used an old central heating pump and a check valve with a stat 1/3 down from top and one at the bottom. The mains power is supplied via a relay from my proportional controller which detects that stat on immersion has cut out.

 

[CBR600]

Thanks pmcalli, it is the controller I am after not the ability to circulate water. My immersion is at the bottom of the cylinder.

 

[inie meanie]

Glad the units are working well.

Some users have recommended this pump
DC 12V Electric Centrifugal Water Pump 103 GPH (P-38I) | eBay Search eBay for P-38I pump if the link does not work. But it’s 10 times the flow needed so needs throttling or running for short periods. Smaller pumps that have reliable pipe connections are not easy to find.

.

Hi All. Just a quick note on the ebay pump. I fitted a small non return valve, as you could draw cold water into the hot outlet, and this slows the flow rate perfectly. I use two thermostats 1/3 rd down and just above the inlet at the base of the tank, both set at 60. It works perfectly. The threads shown are 1/2 bsp so easy to buy fitting for. It's cheap quiet and effective. :- )

 

[Duplada]

Credit for my pumping system goes to inie meanie above who pointed me in the direction of the parts to use.

I use the ebay pump above, two thermostats, search ebay for KSD9700 you need one 60 degree thermostat Normally Closed (NC) and one 60 degree Normally Open (NO) The normally closed one fits a third down your tank and the normally open one above the water inlet on the bottom of your tank. Wire these in series with your pump. I use a 12v 1 amp power supply on an old ADSL router for power. I use a Brass Swing Check Valve to stop back flow search BES or ebay.

T a 22mm pipe from the top of your cylinder to the pump and from the pump to a T into the cold water inlet to your cylinder, put the none return valve between the cold water inlet and the pump outlet to stop back flow. Good idea to use two isolating valves at each end of your pipe run for maintenance and emergencies.

I have created this crude diagram of how everything fits together.

I hope this helps

regards Duplada

View attachment 14090

 

[pmcalli]

Credit for my pumping system goes to inie meanie above who pointed me in the direction of the parts to use.

I use the ebay pump above, two thermostats, search ebay for KSD9700 you need one 60 degree thermostat Normally Closed (NC) and one 60 degree Normally Open (NO) The normally closed one fits a third down your tank and the normally open one above the water inlet on the bottom of your tank. Wire these in series with your pump. I use a 12v 1 amp power supply on an old ADSL router for power. I use a Brass Swing Check Valve to stop back flow search BES or ebay.

T a 22mm pipe from the top of your cylinder to the pump and from the pump to a T into the cold water inlet to your cylinder, put the none return valve between the cold water inlet and the pump outlet to stop back flow. Good idea to use two isolating valves at each end of your pipe run for maintenance and emergencies.

I have created this crude diagram of how everything fits together.

I hope this helps

regards Duplada

View attachment 14090

I found that I needed an air vent before the pump but this is probably because I am using an old CH pump

 

[Duplada]

I found that I needed an air vent before the pump but this is probably because I am using an old CH pump

This is true because the ebay pump is not self priming, but you can slacken the connection to the pump slightly to let the air out to get it started.

regards Duplada

 

[CBR600]

Has anyone got a view on the patent that has been awarded to Coolpower for their EMMA unit? It seems to suggest that they have a patent over any form of domestic load manager where the there are two forms of supply. I have had a look through it and on page 10 claim 1 it is pretty specific about the operation of the unit so I am not sure what impact this might have on other similar devices as long as they operate in a different way.

This is a link to the patent;

Intellectual Property Office - Patents publication enquiry

 

[methley]

@Duplada - That's a really neat solution using two thermostats (although I think you got them the wrong way up in your description?). How noisy is the Ebay pump compared to a central heating pump on its lowest setting?