New boiler worry

callmechar

Had a new Worcester 18ri fitted last week.

Looked through installation manual and it says Co2 should be minimum 9.2% with a tolerance plus or minus 0.5%. The Co2 reading from my boiler is 8.2%

Spoke to plumber who said this is ok, the "high flame was good"

He has noted on warranty form this is low

Is this a problem? I have no idea what all this means.

keystone

I don't think you have anything to worry about.


Cheers

Canucklehead

callmechar wrote: »

Had a new Worcester 18ri fitted last week.

Looked through installation manual and it says Co2 should be minimum 9.2% with a tolerance plus or minus 0.5%. The Co2 reading from my boiler is 8.2%

Spoke to plumber who said this is ok, the "high flame was good"

He has noted on warranty form this is low

Is this a problem? I have no idea what all this means.

In your other thread one of the RGIs mentioned the gas supply needed to be upsized from 15 mm to 22 mm. What did your chosen RGI do?

Canucklehead

Canucklehead

keystone wrote: »

I don't think you have anything to worry about.


Cheers

Poor show if the RGI is unable to commission the appliance within WB specs.

Canucklehead

keystone

Canucklehead wrote: »

Poor show if the RGI is unable to commission the appliance within WB specs.

Canucklehead

OPs 8.2% is LESS than the stated 9.2% CO2 a minimum rated heat output after 30 minutes. So its actually better than WB specs and yes I did have to look it up.

Cheers

callmechar

keystone wrote: »

OPs 8.2% is LESS than the stated 9.2% CO2 a minimum rated heat output after 30 minutes. So its actually better than WB specs and yes I did have to look it up.

Cheers

Hi yes its 22mm now from the boiler.

So is the fact its less than the minimum good? I do not understand this. From someone who doesnt understand, it looks like this is a bad thing?

callmechar

Canucklehead wrote: »

Poor show if the RGI is unable to commission the appliance within WB specs.

Canucklehead

so this is bad or good? RGI is approved by WB

keystone

No you misunderstand. The WB spec is for the beastie to produce not more than 9.2% CO2 in the flue gases at the minimum rated heat output of the boiler and not more than 9.8% at the maximum rated heat output. Both after 30 minutes operation. Yours is producing less CO2 so its better than spec.

Cheers

callmechar

keystone wrote: »

No you misunderstand. The WB spec is for the beastie to produce not more than 9.2% CO2 in the flue gases at the minimum rated heat output of the boiler and not more than 9.8% at the maximum rated heat output. Both after 30 minutes operation. Yours is producing less CO2 so its better than spec.

Cheers

Thank you. I still am a bit confused? Why does it state minimum of 9.2 though if in fact it could be lower like mine is. From someone who has no clue, this appears to be not doing as it should be. If it can be less like mine, should this not be in the tolerance? Sorry if I sound completely clueless, on this I am! I

keystone

If you are looking at the same doc as me whch is the benchmark it doesn't say a minimum of 9.2% CO2 in the flue gasses at all. The specification says 9.2% CO2 at minimum heat output after 30 minutes operation. You have 8.2% so you are producing LESS CO2 than the manufacturer says is acceptable so it has to be better. If you were producing 10.2% then that would be different.

Look at it this way then: 9.2% is the passmark. 10.2% is outside spec and a fail. 8.2% is within spec and is a pass.

Cheers

gas4you

8.2% is way too low for this boiler.

As Keystone rightly says it should be 9.8/9.2 %, but unusually I have to respectfully disagree with his comments about the boiler running at 8.2% minimum. (Sorry Keystone)

With such a low reading on minimum, you will, or may eventually get ignition lockouts.

You also may get the boiler shutting off when it modulates down, rather than just ticking over on minimum.

Has your installer said he cannot set the minimum to 9.2%, or does he just not know how?

There are lots of installers who just fit a boiler on the wall and leave it.

What is the working pressure at the gas meter and the inlet pressure at the boiler gas valve?

Your installer should have checked both of these with such a problem as this.

I also hope he gas rated the appliance at full power, whilst in your case I would have also gas rated it at minimum power as well.

On the face of it, setting the gas valve on one of these is a POP.