Only Very Occasional Hot Water From Central Heating

Hi

When you run your hot water does the boiler light?

If it doesn't then the fault is probably with the flow sensor.

If it does light, can you check and see if the radiator pipes become warm. If they do, that suggests the fault is with your diverter valve.

Regards,

Steve

I'm curious as to how the almost total lack of hot water is only a problem in winter ?

That aside, presumably you have a combi boiler - one that is supposed to provide instant hot water on demand - and not a stored system with a hot water cylinder ? As has been suggested, the flow sensor could be faulty (causing the boiler not to light or the fan not to come on), or the diverter valve may be stuck (causing the heated water to be circulated through the radiators rather than the internal heat exchanger which actually heats the cold mains water). You should be able to diagnose what is or isn't working and report back.

Oh, and you should probably sack your plumber. To "service" a boiler (which is doing virtually nothing[1] on most appliances other than taking the cover off and looking busy while drinking any profferred cups of tea) and then airily dismiss a genuine fault as something you could do yourself[2], is rank amateurism. He just wants an easy life.

HTH.

For those of you new to plumbing, that is a boiler that only fires up when the house is too cold, or when you turn a hot tap on. It then delivers a thin trickle of hot water to maybe one tap if you are lucky. ;-)

Forgot to mention it's a back boiler not a combi boiler.Radiators al

work absolutely fine too

-- kjhi98

Sadly, I've just moved house and that's what I have to put up with now. The idea of not having storage does actually accord quite well with the house inhabitants and their residency patterns, but sadly the reality of a combi boiler is having to wait ages for anything. They're hardly compatible with the idea of saving water.

Cue Drivel and his usual suggestion of doshing out enormous amounts to replace one functional boiler for another with heat store...

My sister had a combi in a medium sized 4 bed house in Germany. It was the size of a small car. I believe there was about 10,000 liters of oil tank as well in the basement. At that size for 4 people it worked well..lord KNOWS what the peak output was..guessing around 70KW.

This house here is twice the size and we do nicely on 13KW of stored hot water sysem boiler.

You must therefore have a HW cylinder somewhere. The first question to ask when someone says they have no hot water is "Do you have cold water or no water from the hot taps?" The next question will probably be something like what type of programmer or time switch do you have?