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Is it possible to have two gas combination boilers connected to the same gas meter?

I'd like to have two combination boilers (one downstairs the other upstairs, and serving likewise) connected to the same gas meter. The problem is I have received confusing messages from builders, some saying that I can, some that I cannot have that on one meter.
The room upstairs is rented out and ideally I'd like the tenant to be able switch her own heating there on and off. But as I'm the one paying gas bill for the whole property, I do not see why I need the second meter. Any advice please?

9 Answers from MyBuilder Gas Engineers

Best Answer

I would strongly recommend you have two meters! most combi boilers at full rate require 3 m3/hr+ so the usual meter E6/U6/G4 Can only supply 6 m3/hr. So you do the maths! THIS COULD IF YOU GO AHEAD CAUSE AN AT RISK INSTALLATION! Your meter must have a working pressure of 21mbr +/- 2mbr,your not going to get that! There must be no more than 1mbr drop between the meter and the boilers working pressure! you aint going to get that!
Zoning the heating will be costly,and require a system boiler,different pipe work ,zone valves,two stats. You only have to zone a system over 3-4 floors etc etc.
Everybody above me is right in there own way!!!! some haven't thought about it on the load front!

regards kieran


Answered 15th Feb 2012

Hello, yes, its perfectly fine to have them from the same meter.

The only reason to have a secondary meter would be for billing purposes.

If your happy with arrangements for bills then no reason to get an extra meter.

I would say however that the pipework will need to be adequate to cope with 2 combi's running at top rate so maybe you will need to come off the meter with 28mm pipe before tee-ing off to smaller sizes.
Your installer should be able to test that the boiler's are working to the correct rate upon commissioning.



Answered 25th Aug 2011

you can have both off one meter as there is only one bill payer.both boilers must have enough gas to work correctlyso it would depend on incoming gas pressure and corect pipe sizing but idealy and more than likly you will need 2 meters.


Answered 25th Aug 2011

hi, rather than have two combis you could multizone (room thermostats upstairs and downstairs) your heating off a new system boiler and it would be cheaper than two boilers. hope this is helpful adrian


Answered 28th Aug 2011

Change the pipe work and incorporate 2 zones each controlled by a programmable room thermostat in their own area, include thermostatic valves to each radiator for maximum control of both zones. this will save you buying and servicing a second boiler by far a better way of proceeding.
hope this helps


Answered 10th Sep 2011

yes you can, a domestic meter can deliver 65kw of gas per hour so as long as the 2 combi’s or a combination of gas appliances don’t exceed that and the correct pipe sizeing has been calculated you will fine


Answered 31st May 2018

If the pipework and meter are of sufficient capacity there would be no problem. The installing Engineer will have to check this anyway.

Regards Simon


Answered 26th Aug 2011

yes ifitted correctly shouldn't be a problem


Answered 5th Apr 2016

Yes can be done
As long as engineer checks theb working pressure at appliance , gas pipe prob needs to be increased


Answered 7th Sep 2019

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