Gas water heating - timed or constant?

Bogof_Babe

Would love people's views on whether it is more economical in the winter to keep the gas water heater set on constant, or to let it cool down and start from scratch twice a day?

We have a back-boiler for water and the central heating, and also an electric immersion water heater which we rarely use unless needing a back-up for high demand.

At the moment the gas system fires up at 5.30 a.m. and goes off at 8.00, then again at 4.30 p.m. to 9.00. Would it be cheaper to have it continually cutting in and out, so that it never runs cold?

trafalgar_2

If you rarely use hot water then it may be cheaper to do it in spurts but if your like us.......3 in house...............and use often then it is absolutely cheaper to leave it on

Bogof_Babe

Thanks Traf (if I may be bold and use your shortened name that I have seen elsewhere ). There are just two of us, but I am at home nearly all day for most of the week, and tend to switch it to constant automatically for washing dishes etc. (our cats are heavy on dishes ::)) so it might as well be left on anyway.

Just got to convince my hubby now - he reckons it wears the pump out ::).

trafalgar_2

"Just got to convince my hubby now - he reckons it wears the pump out"

Men................lol ;D

It will definately be cheaper if your home all day

shanni

I've often wondered this. I have a combi-boiler in my small flat. Is it the same answer? I'm out most of the day but pop home lunchtimes. There's only me and 2 cats! My flat is so small I only have 4 radiators (but no dbl glazing). Is it cheaper for me to leave it on low or have 2 timed periods?
Thanks anyone

trafalgar_2

It all depends.......if you have a big tank of water that gets heated,then it's cheaper to keep it heated .

shanni

Thanks Trafalgar,

I've no idea about the boiler, I didn't think there was one with combi's but I could be totally wrong. Perhaps it's in the attic.

I'm really tight with heating and hardly use any hot water (elec shower). I usually get into bed with my elec blanky and a cat on each foot!

Thanks, :-*you've helped me in a couple of places. This site is really good isn't it.

hilstep2000

I recently had loft insulation fitted under the goverments homewarm scheme, and the man who assessed me said that to heat a tank of water only takes an hour, I was keeping mine on for three hours at a time, he reckons cutting the timer down to an hour will save me £60 a year at least!

MATH

I used to time my immersion for 3hrs every morning and a 1hr boost in the afternoon until my mate told me it will heat a full tank in 1 1/2 hrs. Now I time it for 2 1/2 hrs in the morning when we're drawing off water and do not need to boost in the afternoon.

t8769

Most people forget about the pipes.

For only £5 you can pick up insulating foam from Homebase, which clips around the pipes.

How water pipes around a boiler or tank give off masses of heat. Save yourself a packet by insulating them thoroughly.

TimBuckTeeth

trafalgar wrote: »

If you rarely use hot water then it may be cheaper to do it in spurts but if your like us.......3 in house...............and use often then it is absolutely cheaper to leave it on

Absolutely wrong.
It is more expensive to leave it on, no matter how many people in the house.

It uses more gas to keep the water hot, the hotter the water in the tank the greater the heat loss from the tank. A cold tank doesn't lose (waste) any heat.
If the water is heated in the morning and not all used it should stay fairly hot until the evening, if it doesn't then the tank needs better insulation.
It still is cheaper to heat a full tank from cold than try and maintain a constant temperature, especially if the tank is not well insulated.

A hour in the morning and a hour in the evening (or longer if you use a lot of hot water) is the cheapest. Just enough water should be heated soon before it is needed.