Combi boiler- How water not that hot anymore

[Geordie Spark]

"Hello puddy",


Well done for `researching` about your Boiler / Heating & Hot Water requirements and sticking to what You wanted.

There are various Combination Boilers that are advertised by the Manufacturers to be able to suppy `High Hot Water demand` properties - for example the Ravenheat CSI 150 - a `42 KW Combi` - the published Hot Water supply specifications are:

D.H.W. FLOW RATE 30 °C rise 20.1 l/min

D.H.W. FLOW RATE 35 °C rise 17.3 l/min

D.H.W. FLOW RATE 40 °C rise 15.1 l/min

These stated Temperature rises are from a 10°C Cold Mains inlet temperature.


BUT - the Hot Water outlet pipe from the Combi is still only a 15mm Pipe - so it would still NOT be suitable to run Hot Water to TWO Hot Water outlets / Taps / Showers - especially if they were any distance [pipework] from each other.



Regards,


Chris - Heating Engineer - Registered Gas Engineer.

What size is the Gas Supply pipe for that one Chris?

I'm guessing it's probably 28mm

 

[chris murphy]

What size is the Gas Supply pipe for that one Chris?

I'm guessing it's probably 28mm

"Hello Geordie Spark",


When I posted My message to puddy I had not looked at the Gas Rate / Gas Connection size for the Ravenheat `42 KW` Combi.

I had just seen an Advert for it in the `Installer` Magazine - January Edition and I have the Installation Instructions on File so I looked for the Hot Water Flow Rates to include in My message.

NOW - After You asked about the Gas Supply size I went back into the Installation Instructions and looked at the Gas Rate / Inputs and Outputs - NOWHERE is this `42 KW` Input shown.


AND - The Gas Supply connection is 15mm - ! !

Obviously We would be calculating the Gas Pipework Size / Resistance and running the appropriate size to within a short distance from the Combi Gas Inlet Connection.


Here are the published specifications [From Ravenheat] for the Gas Consumption / Input & Outputs:



NOMINAL HEAT INPUT NET QMS 32.0 kW

MINIMUM HEAT INPUT NET 8.0 kW

NOMINAL HEAT OUTPUT 31.7 kW

NOMINAL HEAT OUTPUT CONDENSING 34.9 kW

MINIMUM HEAT OUTPUT 7.93 kW

MINIMUM HEAT OUTPUT CONDENSING 8.73 kW

GAS RATE max 3.4 M3/Hr - AFTER 10 MINUTES min 0.85 M3/Hr

INLET PRESSURE 20 mbar

I have not done any Calculations regarding the Gas Supply / Pipe Size examples as yet as I am just about to have Dinner and also My Gas Pipe Calculation Tables are not to hand.

EDIT: The comments below are not directed at You Geordie Spark - they are for other Members / interested parties:

EDIT: THESE COMMENTS ARE BASED ON SOME VERY QUICK / `ROUGH CALCULATIONS:

In an `Average Home` [If there is such a thing] - guessing that the Gas Meter would probably not be more than about 12 / 15 Metres [pipework length] from the Combi and that there could easily be other Gas Appliances in the Home - Cooker / Gas Fire:

Allowing for the necessary Elbows and Tee Fittings 22mm Pipework from the Meter to the Combi would NOT be adequate to Supply the `Maximum Gas Rate of 3.4 M3 per Hour` when the other Appliances Gas requirement and the Resistance of the Fittings / Pipework is calculated.

Obviously depending on the layout of the property and the location of the Appliances there would be a requirement for at least one section of the Pipework to be `Upgraded` to 28mm from the Meter.

Again depending upon any other Appliances - there could then be a decrease at some point to 22mm which I would then run to just under the Combi before reducing to 15mm - although in this particular case the Manufacturer states that the last 3 Metres can be in 15mm Pipe.

Here is a Link to the Ravenheat Literature Download webpage for this Combi - in case You are interested in looking at the Installation Instructions / Specifications:

http://www.ravenheat.co.uk/images/manuals/CSI120-CSI150-manual.pdf


"Happy New Year".


Regards,

Chris

 

[Vegelen]

If you dont want to replace your boiler for another with improved flow rate,

What about installing an Eco Flow Shower head?

It uses 40% less water at a lower flow rate, but gives a similar experience to higher flow rate conventional shower heads.

It may not solve your problem, but it should warm up the water leaving your shower head slightly, whilst reducing your water bill.

Waterpik Showers Videos

http://www.waterpik.com/shower-head/ecoflow.htm

 

[chris murphy]

Have you thought of installing an Eco Flow Shower head?

They use 40% less water with a lower flow rate, but give a similar experience to higher flow rate conventional shower heads.

Waterpik Showers Videos

http://www.waterpik.com/shower-head/ecoflow.htm

"Hello Vegelen",


The Eco Flow Shower Head might help the Original Poster to have a more acceptable Shower - well done for posting these Links about it - although I would not expect the OP to respond to your message.

It might help other Members / Readers - in conjunction with adjusting the Hot Water Flow rate via the Shower Valve which will probably still be required - even with the `40% Less Water Use` of the Shower Head.

We have already tried to advise the Original Poster about adjusting the Hot Water Flow rate through the Shower - by simply adjusting the Flow with the Shower Valve - to reduce the Hot Water Flow through the Combination Boiler to a level where the Water will be able to be heated to an `acceptable temperature`.

He has NOT even bothered to respond to Us - I am guessing that He either does not agree with what we have stated or just cannot be bothered to respond as the Answers are `Not to His Liking`[?].

I may be wrong about this - BUT - to just not even acknowledge our Answers to Him is simply Bad Manners - unless He has had some kind of Emergency - which obviously I hope not.




For the benefit of other Members / Readers - and because there is a `New Device` on the Market which claims to address this exact Hot Water problem - I will now give some details about it:


There is a New product specifically designed to help with this `Hot Water from a Combi not as Hot in Winter` problem - But as I do not have all of the details about it - AND because of the OP NOT responding to Our Advice - I have NOT mentioned it up to now on this thread - it is called the `COMBISAVE`


I AM NOT RECOMMENDING THIS PRODUCT - I HAVE NOT EVEN HAD TIME TO LOOK AT WHATEVER INFORMATION IS AVAILABLE ABOUT IT - BUT IN CASE THAT IT IS SOMETHING THAT COULD HELP THOSE IN THIS SITUATION:


`COMBISAVE` - `IMPROVE BOILER PERFORMANCE IN WINTER`

www.combisave.com



Something that occurs to Me immediately about this product is that Combination Boiler Manufacturers would probably be VERY unlikely to Approve the fitting of this `Thermostatic Control` to the Hot Water Outlet Pipework of their Combi`s.

Although it may be a `Water Supplier Approved device` - regarding the statement that it will `Save Water` - I cannot imagine that a Combi Manufacturer would approve ANY device that would Reduce / `Delay` the Hot Water Flow through the Boiler Heat Exchanger.

Because the device could malfunction I would not class it as the same as a Thermostatic Valve / Thermostatic Shower Valve - OR the same as reducing the Hot Water Flow rate through the Combi using a Tap / Shower Valve Control.

I have seen the British Gas and NPower Logo`s on the website as Installers of this product so there must either be some Manufacturer`s approvals or these Utility Companies must have decided that there is NO Issue regarding fitting these devices to Combination Boilers [?] - but I do not know about that.

Installing one of these on the Hot Water Outlet pipework from your Combination Boiler without getting approval from the Manufacturer [probably very unlikely] MAY cause the Appliance to become either `Faulty` - or possibly even Dangerous.



This is just My Opinion - I could be wrong about this - BUT there will definitely be Combination Boilers which would NOT be suitable to have this device fitted to the Hot Water Outlet Pipework - for example Combis with a Thermal Store or a Hot Water Storage Cylinder / some Combi`s with a Preheat Tank.

This should be researched very carefully by contacting the Manufacturer of your Combi at the very least - IF you are contemplating having one of these fitted.


I hope that this is helpful to some Members / Readers - Please remember - I am NOT recommending this Device / `Thermostatic Control`.

Regards,


Chris - Heating Engineer - Gas Engineer - Plumber / Heating, Plumbing & Gas Contractor

 

[puddy]

The Eco Flow Shower Head might help the Original Poster to have a more acceptable Shower - well done for posting these Links about it - although I would not expect the OP to respond to your message.

I was going to suggest that we got a small plastic disc that said insert in between showerhead and pipe to save water its was shoved though the letter box one day

He has NOT even bothered to respond to Us - I am guessing that He either does not agree with what we have stated or just cannot be bothered to respond as the Answers are `Not to His Liking`[?]

.


Even the words thank you for your help would be nice. It would only take few seconds

There is a New product specifically designed to help with this `Hot Water from a Combi not as Hot in Winter` problem - `COMBISAVE` - `IMPROVE BOILER PERFORMANCE IN WINTER`
www.combisave.com

I am so glad I read up on my replacement boiler!!! Warmfront wanted to fit a combi oil boiler outside, They hadn’t counted all the rads and some rooms had double rads and they missed the on-suite and downstairs loo in the survey. They choose a underpowered boiler which I wouldn’t let them fit and pointed them to bosh website on my laptop. Plus the dreaded Total Trade Services installed it.

They said it would take 3 days max to fit new oil tank and oil wall mounted boiler bosch boiler it took 2+ years before it was done correctly. They put the oil tank to close to wooden fence all there oil joints leaked caused £1200 damage to boilermate by dry firing it. Counterfeit oftec paper work. No spirovent, 3 hours to wire thermostat.

He had no oftec number used the HQ supervisors number. But the worst of all Total Trade Services did not inform building control of the work. Warmfront had to re-do everything again.

So they brought in a better firm to re do the work. Remove tank lay new base position tank fit fireboard protection to garage re-lay oil line with no joints in this time fit oil filter replace tiger loop remove boiler flue and fit in a different position so gases don’t come in upstairs window. Fit missing spirovent fit thermostat
Repair boilermate new circuit board 2 new pumps and replace backup water element and 2 sensor

Make good garden


I am glad they wasn’t a gas boiler all those leaks could killed us. TTS where a disgrace to your profession

Something that occurs to Me immediately about this product is that Combination Boiler Manufacturers would probably be VERY unlikely to Approve the fitting of this `Thermostatic Control` to the Hot Water Outlet Pipework of their Combi`s.

Although it may be a `Water Supplier Approved device` - regarding the statement that it will `Save Water` - I cannot imagine that a Combi Manufacturer would approve ANY device that would Reduce / `Delay` the Hot Water Flow through the Boiler Heat Exchanger.

Because the device could malfunction I would not class it as the same as a Thermostatic Valve / Thermostatic Shower Valve - OR the same as reducing the Hot Water Flow rate through the Combi using a Tap / Shower Valve Control.

I have seen the British Gas and NPower Logo`s on the website as Installers of this product so there must either be some Manufacturer`s approvals or these Utility Companies must have decided that there is NO Issue regarding fitting these devices to Combination Boilers [?] - but I do not know about that.

Installing one of these on the Hot Water Outlet pipework from your Combination Boiler without getting approval from the Manufacturer [probably very unlikely] MAY cause the Appliance to become either `Faulty` - or possibly even Dangerous.

Site Forman said don’t fit if you have a boilermate 2000 it’s all done on flow and return temps when calling for heat or water its onboard chip gets confused I am sure you have come across them at some time? I like them but don't know how you guys feel when you find them in a property

 

[chris murphy]

"Hello again puddy",

Thanks for posting a reply to what I wrote - Sorry to read that You have had some VERY Bad experiences with a `Heating Installation Company` - ending up with what seems to have been a `Disasterous Heating / Boiler / Oil Tank Installation`!


Could You please help Me to understand something that you wrote about a Quote from one of My posts:

Originally Posted by chris murphy:

Something that occurs to Me immediately about this product is that Combination Boiler Manufacturers would probably be VERY unlikely to Approve the fitting of this `Thermostatic Control` to the Hot Water Outlet Pipework of their Combi`s.

Although it may be a `Water Supplier Approved device` - regarding the statement that it will `Save Water` - I cannot imagine that a Combi Manufacturer would approve ANY device that would Reduce / `Delay` the Hot Water Flow through the Boiler Heat Exchanger.

Because the device could malfunction I would not class it as the same as a Thermostatic Valve / Thermostatic Shower Valve - OR the same as reducing the Hot Water Flow rate through the Combi using a Tap / Shower Valve Control.

I have seen the British Gas and NPower Logo`s on the website as Installers of this product so there must either be some Manufacturer`s approvals or these Utility Companies must have decided that there is NO Issue regarding fitting these devices to Combination Boilers [?] - but I do not know about that.

Installing one of these on the Hot Water Outlet pipework from your Combination Boiler without getting approval from the Manufacturer [probably very unlikely] MAY cause the Appliance to become either `Faulty` - or possibly even Dangerous.


End of Quote


Your reply to that quote:




Site Forman said don’t fit if you have a boilermate 2000 it’s all done on flow and return temps when calling for heat or water its onboard chip gets confused I am sure you have come across them at some time? I like them but don't know how you guys feel when you find them in a property

End of your reply


I am NOT trying to be `Funny` / Awkward here:

I was commenting on the `New` Product that I mentioned in My post - the `Combisave` - I cannot see what You meant when you used the Quote in relation to your reply to it - ?



Could You please post a reply to explain what You meant - "Thanks".



Regards,



Chris

 

[puddy]

Could You please help Me to understand something that you wrote about a Quote from one of My posts

All its about was energy saving devices and why I was told not to fit them with a Boilermate 2000

Originally Posted by chris murphy:

Something that occurs to Me immediately about this product is that Combination Boiler Manufacturers would probably be VERY unlikely to Approve the fitting of this `Thermostatic Control` to the Hot Water Outlet Pipework of their Combi`s.

Although it may be a `Water Supplier Approved device` - regarding the statement that it will `Save Water` - I cannot imagine that a Combi Manufacturer would approve ANY device that would Reduce / `Delay` the Hot Water Flow through the Boiler Heat Exchanger.

Because the device could malfunction I would not class it as the same as a Thermostatic Valve / Thermostatic Shower Valve - OR the same as reducing the Hot Water Flow rate through the Combi using a Tap / Shower Valve Control.

I have seen the British Gas and NPower Logo`s on the website as Installers of this product so there must either be some Manufacturer`s approvals or these Utility Companies must have decided that there is NO Issue regarding fitting these devices to Combination Boilers [?] - but I do not know about that.

Installing one of these on the Hot Water Outlet pipework from your Combination Boiler without getting approval from the Manufacturer [probably very unlikely] MAY cause the Appliance to become either `Faulty` - or possibly even Dangerous.

End of Quote

Your reply to that quote:

Site Forman said don’t fit if you have a boilermate 2000 it’s all done on flow and return temps when calling for heat or water its onboard chip gets confused I am sure you have come across them at some time? I like them but don't know how you guys feel when you find them in a property

End of your reply

I am NOT trying to be `Funny` / Awkward here:

I was commenting on the `New` Product that I mentioned in My post - the `Combisave` - I cannot see what You meant when you used the Quote in relation to your reply to it - ?
Could You please post a reply to explain what You meant - "Thanks".

When I moved to my present home we found that there was no hot water tank and it had been replaced with a device called a Boilermate 2000. When you move to a new housing development you tend to be given freebee’s. The enclosed box had 4 low energy bulbs and includes devices to screw on or attached disk to your taps that meant you would save water if you fitted them

But

The site foreman told is not to fit them

This has nothing to do at all about the Combisave product if you had worked on a Boilermate 2000 you would understand why the devices I was given free should not be fitted.

It seems when computer chips take over any devices not approved by a boilermaker you could knock out fine tolerances that could cause problems. It’s a bit like getting your car engine ECU chipped. Have you worked with a Boilermate 2000?

I am not sure if your building insurance would pay out if you fitted things to your boiler without speaking to the manufacture first. Insurance companies use every trick in the book not to pay out

 

[chris murphy]

All its about was energy saving devices and why I was told not to fit them with a Boilermate 2000


Site Forman said don’t fit if you have a boilermate 2000 it’s all done on flow and return temps when calling for heat or water its onboard chip gets confused I am sure you have come across them at some time? I like them but don't know how you guys feel when you find them in a property

End of your reply



When I moved to my present home we found that there was no hot water tank and it had been replaced with a device called a Boilermate 2000. When you move to a new housing development you tend to be given freebee’s. The enclosed box had 4 low energy bulbs and includes devices to screw on or attached disk to your taps that meant you would save water if you fitted them

But

The site foreman told is not to fit them

This has nothing to do at all about the Combisave product if you had worked on a Boilermate 2000 you would understand why the devices I was given free should not be fitted.

It seems when computer chips take over any devices not approved by a boilermaker you could knock out fine tolerances that could cause problems. It’s a bit like getting your car engine ECU chipped. Have you worked with a Boilermate 2000?

I am not sure if your building insurance would pay out if you fitted things to your boiler without speaking to the manufacture first. Insurance companies use every trick in the book not to pay out

"Hello puddy",

Thanks for your reply - sorry that it was not obvious to Me that You were agreeing with Me on NOT just retrofitting ANY item to a Heating / Hot Water Appliance - certainly not without obtaining the Manufacturers Approval - which I stated to be VERY unlikely for MOST Devices.

I have NOT worked on a BoilerMate 2000 - this is because I am a Heating, Plumbing & Gas Installation Contractor - NOT a Boiler Engineer / `Service & Repair Engineer`.

Also I believe that these Appliances are almost always installed on New Build Developments and there have been not many `Estates` created in the area of London where I operate - nor do I Contract for any Developers / Estate Builders who would possibly have installed these Appliances in their developments.

BUT - I am a Heating Engineer and if I read the Installation & Maintenance Instructions for ANY Domestic Heating Appliance I would then understand the specification / operation of it.

AND: I already know NOT to just Fit ANY `Energy / Water Saving Device` to a Heating / Hot Water / Gas / Electrical Appliance without the Manufacturers Approval.

I was stating / advising this in the message that You quoted.

I have heard just a few comments in the past from Boiler Engineers / `Heating System Maintenance Engineers` regarding the Boilermate 2000 and later models - some positive - some negative - naturally because these Engineers will probably have been called in to rectify a Fault / Service the Appliance they may have slightly biased views on the Boilermate 2000 and the later models [?] - especially as these Appliances are relatively `Rare` in most areas.



I have NOT heard enough OR ever `Researched` these `Boilermate 2000` Appliances enough to have any Technical comment on them.


Your point on Home Insurance is well made - I have stated this a few times on the Forum previously - ANYTHING that is fitted to a Gas Appliance that is NOT either fitted or APPROVED by the Manufacturer could easily be pointed out by an Insurer as the Appliance having been `Modified` / `Not as Manufactured`.

The Insurers / `Loss Adjuster` will have Gas Engineers who they can call out as a matter of course when there is a Claim which is related to a Gas Appliance - these Gas Engineers WILL be looking for ANY reason to allow the Insurer to refuse the Claim.

In the event of a problem with / caused by the Appliance - the Homeowners / Occupiers Home / Contents Insurance could be `Null & Void` !


Regards,



Chris - Heating Engineer - Registered Gas Engineer - Plumber / Heating, Plumbing & Gas Contractor.