Is boiler underspec?

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Did Worcester visit? Did they do a heat loss calculation? Do you operate the heating on a timed ON/OFF schedule? Does your disability mean you are house bound?
I am using a Google Nest and schedules and self-learning have been removed. There seemed to be an issue when the Thermostat was connected to WIFI in that the temp would stay at 16C. Disconnecting the thermostat from the network allowed the temp to get to around 19C, still not enough though.

I am pretty much house bound and the boiler is in the loft along with the Google Hat Link which I think should be located downstairs if I need to get to it.
 
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I'd suggest you turn up the outlet temperature of the boiler. On the basis that your boiler is a condensing model (it should be) the figure of 55 is reckoned to be the latent heat recovery temperature on the return from the radiators, so your installer probably set things up incorrectly.
If the radiator delta-T (the difference between the temperature entering them and that leaving them) is around 15 to 20 degrees then the boiler will still be performing 'efficiently' with an outlet set temperature of say 70 degrees. Yes, it will burn a bit more gas to get up to this temperature but it will heat up the house faster and hence satisfy the room thermostat setting. I take it your thermostat is an analogue type rather than a simple ON-OFF. If the latter then you need to get this changed to improve boiler efficiency and hence reduce gas consumption.
I have sent the heating engineers an email, so hopefully they will resolve the issue for me.

It is a heat only oiler by the way located in the loft which is a no go for me due to my disability
 
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Assuming this was installed after June 2022, a full room by room heat loss survey should have been carried out in order to comply with Building Regulations prior to specifying the new boiler
Yes, the boiler replacement was installed 2 weeks ago. I on't think a heat loss survey was carried out. I will confirm but pretty sure not.

Thanks for that.
 
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Are you saying the boiler should be adjusted from 55C to 75C?

I remember you saying that your old boiler was running at 60C. How did you know that? Many older boilers would usually run at about 75C. As Johntheo5 mentioned, if the water going to the radiators is 75C, they will give out about twice as much heat as at 55C.
 
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Are you saying the boiler should be adjusted from 55C to 75C?
Temporarily perhaps.
Certainly not permanently.

55C is required to comply with building regulations, also applicable from June 2022 along with the heat loss survey.
 
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What power was the old boiler?

If you have radiators then they have probably been designed to provide enough heat output when supplied at 80C.

If you are only running the new boiler at 55C then the radiator heat outputs will only be about half of that at 80C.

But if the house has four bedrooms then are you occupying them all? If not then have you turned off the rads in the unused rooms?

With the current high price of gas you will need to do everything possible to reduce consumption. Turning off rads in unoccupied rooms and turning down the room stat to 18C to 19C and wearing a thick pullover! And checking loft insulation is up to the recommended minimum thickness of 270mm
 
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Temporarily perhaps.
Certainly not permanently.

55C is required to comply with building regulations, also applicable from June 2022 along with the heat loss survey.
And therein lies the problem. 55 might well be adequate for a well designed and insulated new build with either under-floor heating or radiators sized to suit the thermal losses and the lower operating temperature. But an old house with existing radiators that were running at 70+ won't have a cat in hells chance if a new boiler is to comply with the regulation unless the radiators are resized to suit the new running conditions. (or the regulation is ignored on the basis of exceptional circumstances and the boiler is reset to run at 70+)
 
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unless the radiators are resized to suit the new running conditions
There is the answer.
If a new boiler also requires some or all new radiators, then that is what must be installed together with the new boiler.

55C flow temperatures should have been mandatory 15+ years ago when condensing boilers were introduced.
 
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If a new boiler also requires some or all new radiators, then that is what must be installed together with the new boiler.

Are you saying that, when I replace my boiler, I will have to fit new radiators, if the current ones can't produce enough heat at 55C?
 
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The regulations are designed to make an installation future proof.

Gas boilers are more efficient with a 55C flow temperature but not that much more.

The regulations is designed to enable them to run from an electric heat pump. That is flawed thinking by the Gov who seem not to understand that heat pumps are only as green as the electricity that powers them.

We have failed to replace nuclear power stations and to install new ones to replace gas and coal powered stations.

Both France and Ukraine are way ahead of us in this respect.

All because most people do not understand how they work and are frightened of "radiation" which they do not understand and cannot see. So politicians have failed to provide a green electricity generating system just because they cannot risk upsetting people and so we end up with the dreadful global warming. It is worse because there is a very long lead time to install nuclear power stations and only a very few suppliers.

Even the land based green wind turbines are objected to by anyone living near them. And the Gov are again frightened of upsetting them.
 
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I remember you saying that your old boiler was running at 60C. How did you know that?
The last engineer that serviced the boiler told me. But it is possible I misheard, and he was talking about something else. I cant say for certain.
Many older boilers would usually run at about 75C. As Johntheo5 mentioned, if the water going to the radiators is 75C, they will give out about twice as much heat as at 55C.
OK
 
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What power was the old boiler?
18KW

If you have radiators then they have probably been designed to provide enough heat output when supplied at 80C.

If you are only running the new boiler at 55C then the radiator heat outputs will only be about half of that at 80C.

But if the house has four bedrooms then are you occupying them all? If not then have you turned off the rads in the unused rooms?
Not all andrads have been turned off or down in various rooms yes.

With the current high price of gas you will need to do everything possible to reduce consumption. Turning off rads in unoccupied rooms and turning down the room stat to 18C to 19C and wearing a thick pullover! And checking loft insulation is up to the recommended minimum thickness of 270mm
 
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And therein lies the problem. 55 might well be adequate for a well designed and insulated new build with either under-floor heating or radiators sized to suit the thermal losses and the lower operating temperature. But an old house with existing radiators that were running at 70+ won't have a cat in hells chance if a new boiler is to comply with the regulation unless the radiators are resized to suit the new running conditions. (or the regulation is ignored on the basis of exceptional circumstances and the boiler is reset to run at 70+)
Perhaps I should have included that those who dream up these regulations don't live in the 'real' world. In an ideal world we'd all be living in super insulated houses which cost virtually zilch to heat in winter and cool in summer. But we're stuck with what we have and there has to be some degree of compromise between what we wish for (legislation) and what we have and can do (reality) If you live in a victorian sandstone house that was designed and built around every room having a coal fire and serviced by servants then there's not a reaistic option. Heat pumps wouldn't meet the need and one must do what suits. To meet sensible legislation and climate change the best option would be to burn it to the ground, collect the insurance money and build a super efficient house. But that's not a sensible option.
 
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Perhaps I should have included that those who dream up these regulations don't live in the 'real' world. In an ideal world we'd all be living in super insulated houses which cost virtually zilch to heat in winter and cool in summer. But we're stuck with what we have and there has to be some degree of compromise between what we wish for (legislation) and what we have and can do (reality) If you live in a victorian sandstone house that was designed and built around every room having a coal fire and serviced by servants then there's not a reaistic option. Heat pumps wouldn't meet the need and one must do what suits. To meet sensible legislation and climate change the best option would be to burn it to the ground, collect the insurance money and build a super efficient house. But that's not a sensible option.

If you are just replacing a boiler, do these new rules apply?

EDIT: It looks like it just applies if you are fitting a new system or a full replacement system, rather than just a boiler. That makes sense.

Existing properties: New or full replacement (including all radiators and pipework) wet central heating systems should be sized for a maximum flow temperature of 55°C where possible.
 
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