central heating radiators

[shopper]

I have combi boiler central heating with 7 radiators running from it. What I would like to know is, am I saving gas by turning off 3 of the radiators and just heating 4. Or will it use the same amount of gas to heat them all?Thanks

[Catso]

'Course you're saving gas; you're approximately halving the amount you use.

The more rads you use, the colder the water returning to the boiler will be, as moer heat has been taken from it to heat your rads/rooms. So the more gas will be used to reheat teh water back up to the required temperature.

[shopper]

thanks for your answer. it makes sense now youve explained why.