Water Not Getting Hot

[DarceyK123]

Mum has a Vailliant Eco plus boiler (its not a combi)
Although thankfully the heating is working, the hot water is tepid.
Its on the highest setting 75degrees but still tepid.

Trying to get through to BGas but they are "experiencing high levels of calls"

Any ideas in the meantime?

Any help appreciated.

[bhg481]

Just to be clear, are you saying the house warms up perfectly well but hot water from the taps is only lukewarm?
There are probably 3 thermostats on your system. One on the boiler, one on your heating system (possibly TRVs on your radiators as well) and one on your hot water cylinder. If it's only the tap water which is lukewarm it could be that the cylinder thermostat has been knocked or has failed. Alternatively, the diverter valve, which directs the water from the boiler to either the cylinder or the radiators, has stuck in the radiator position. These valves can usually be operated manually but normally default to hot water position.

[bednobs]

ps bg are always experiencing high volumes of calls. i have never known a time they are not!

[youngmafbog]

Turn the HW stat down and listen for the click (that shows the thermostat is sensing) and also for the motor in the tri valve (assuming that is the set-up) which should also move. Could also try turning down the heating. This should force the valve shut to CH and fully open to the HW. You should hear the valve shut.

[The Builder]

I've long suspected that BG's "high volume of calls" is just code for "there's no one here".

The others have said it. Cylinder stat or diverter valve. It's usually the diverter.
The diverter is probably in the airing cupboard. Possibly a metal box sitting on top of the plumbing bit. Tapping this box with a small hammer often frees things up, or taking this "head" off and manually turning the valve over to Hot Water.
If it's a problem with the Cylinder Stat, then it will most likely need replacing.
A few simple tests would identify the cause.

If you don't feel confident to try this, then I would suggest calling out a "proper" heating guy.
In the meantime, switch on the immersion heater to heat up the cylinder.

I'm sure we all wish we could do something to help. Maybe one day, "Remote Assistance" will become available. Then I could do it from here ;o(

[DarceyK123]

Thank you all for your suggestions, much appreciated.