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fred fred is offline
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Default New boiler undergassed. Blame gas meter governor?

In article , John
Rumm writes
On 25/06/2010 22:16, ernie mendoza wrote:

I have just had a new Worcester-Bosch 24i system boiler installed in
the loft to replace a 30-year-old non-condensing boiler in the
kitchen. Tests show it is "undergassed". The installer says it may
be a problem with the gas meter governor, in which case they say
Transco would have to fix it. However the 22mm pipe required by the
boiler is connected to a 15mm pipe from the gas meter. Should the
installer fit a larger pipe to the gas meter instead of blaming the
governor and shifting the problem to Transco? Any advice most
welcome.



Easy enough to check. Just work out if the pipework you have is adequate
for the required flow rate.

Look in your boiler manual[1] for the maximum gas flow rate required by
the boiler in cubic metres per hour. Then use the pressure drop tables
shown he

http://www.copperinfo.co.uk/plumbing...downloads/pub-
124-copper-for-domestic-gas-installations.pdf

To see if your pipework is adequate can deliver the required flow.


[1] Available here if you have not got it:

http://www.worcester-bosch.co.uk/ins...greenstar-24i-
system


In addition, if the installer is suggesting that the meter regulator is
faulty then invite him to measure the pressure at the meter outlet test
point with the o/p present and show that it is out of spec (20mbar
+/-1mbar) with the boiler running flat out. O/P may need to watch out
for smoke & mirrors at this point to avoid being duped by a dodgy
measurement technique.

Finger in the air suggests it should be 22mm to within 20cm of the
boiler but nothing beats the full design process above.

Good info here http://www.makewrite.demon.co.uk/GasFitting.html under:
3 Working on Gas Pipework
a) What size pipes should be used for gas?
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fred
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