Dumb question about hot water timer control

[ProgressPenguin]

I feel really silly asking this as I think I should know what to do by now.

I have a controller for my hot water which I can program with times the hot water comes on and goes off.

How do I know how long to put it on for? I don’t want to waste loads of gas, but then I don’t want us running out of hot water either. What is a good ballpark amount of time? And how far in advance before you use the water do you need to heat it?

At the moment I’ve got it as:
6am-7:30 am to cover mine and DH’s showers
Middle of the day - I don’t use this option, can’t see why I would?
6pm-8pm to cover DC’s bath or bath+shower

Does that sound reasonable? I just don’t have a clue!

Thanks!

How old is your boiler?
I now have a combi boiler (?) That heats water as we need it. In our previous home there were 6 of us and we timed it for an hour in the morning (showers) and 1-1/2 hours in the evening for washing up and baths. Generally needed it turning on about an hour before we needed it.

The easy question is - are you getting hot water when you need it? If it is working for you as it is then don't change it.

I think you could have it on a lot less. We have ours on half an hour in the morning, just before our showers. Still plenty of hot water for dishes and my daughters bath in the evening (and the next day when we didn't quite understand how the boiler worked so didn't turn it on...).

Yes my point is we do get hot water, but I’m not sure if I’m having it on too much and wasting gas.

It must have been a combo boiler I had in my old place as you just turned on the hot tap and the hot water came as needed.

I would reduce it by 15-30 mins am and pm and see what hot water you get. Sometimes it is just guess work and fiddling with the timer.

Agree with @Anyonewhoknows it's an educated guess game. We had a combi which I much preferred as it was so easy but to answer your question there are three of us I have it on for an hour in the morning (now reducing to 45 mins), half an hour at lunch (as I'm on mat leave) and half an hour at 6. So far the morning showers have been fine but I think I can reduce the time, the two half hour stints mean we have hot water for second showers after runs/gym etc and hand washing etc. I am still tinkering at the moment and may reduce the 30 mins to 20 mins and go from there.

A lot depends on how long you shower for, etc.
I would half it (at a weekend so don't miss work if not enough in morning). If that works half again until too little water, then increase in 10% chunks.
You will probably need a little more in winter.

What colour is your hot water tank? Ours has a solid white cover and 20 mins a day is enough for us in the winter, every other day in the summer.

I have the thermostat set at 55c.