Heating Water

[BigDogsWang]

I want to reduce my Gas bills. How long should I have the boiler come on in the morning, to heat enough water for my wife and I to shower (not together!)?

Same in the evenings, for washing up and for the washing machine?

[gasman]

The boiler will cut out when the water is hot enough so it is not relative to how long it is on for. For the most efficeint use of energy have your hot water set to come on 1/2 hr before the heating comes on then the boiler is dedicating all of its energy to just one job at a time and will reduce warm up times compared to when it is heating the house as well as the hot water at the same time and taking twice as long and energy to do so.

[Miss-taken]

Don't know the answer but just wondered why you would need hot water for the washing machine? Surely they only need a cold feed going into them and then the machine heats the water up to the right temperature?

[BigDogsWang]

Don't think so. All my machines have had hot and cold feeds.

Gasman. You say it is not relative how long you have the boiler on for, but surely if you leave it on for two hours, it will keep firing up if the temperature drops? I would have thought it best to have it kick in for half an hour, and to turn off 10 mins before getting in the shower.

[umm]

i solved this problem by buying a rayburn,,the best investment ever made,,runs on solid fuel so burns 24 hours a day for very little money giving me loads of hot water and roasting radiators,,

[BigDogsWang]

Thanks for the suggestion umm, but I dont think it's very practical in a 3 year old house made out of cardboard :)

[gasman]

BigDogsWang,
With the Hot water cylinder cylinder properly insulated, it will take quite a long time for the temperature to fall enough for the boiler to kick in again . It uses more energy to heat up from cold than it does to just top up the heat when it has dropped a few degrees. It will not be firing up every ten mins or so, more like a few hrs between top up. Then it will only be on for a few mins because the water will only need to be heated a few degrees instead of trying to heat a full cold tank.