Heating Water Through Central Heating or Immersion? Cheapest?

[blobert]

Hello,

I've recently moved into an apartment with gas central heating. When the central heating is on for some time it seems to heat the water also. So far this is fine as we have the central heating on as its been cold.

As the weather improves I'm not sure whether it is likely to be cheaper to heat water for showers etc by having the central heating on (with all the radiators switched off) or via the immersion?

The central heating option is handier in that there is a timer so I can set it to come on an hour before I get up in the morning but is it likely to be cheaper than the immersion.

I know in general electricity is the most expensive way to heat water, just wanted to make sure that this is the case. I can fit a timer to the immersion if needed, as I say, if gas is cheaper then that will be the way to go.

I'd appreciate any advice.
Thanks

 

[DGOBS]

There should be a valve in your hotpress that will shut of the rads (all all the pipework to them) leaving the boiler heating dhw only, and yes, heating via gas is cheaper, immersion is the most expensive way to go

 

[davidoco]

see above