Boiler issue - Heating only works if hot water switched on

[Roofies]

Hello. I have different switches to heat water and to turn on hot water supply to the radiators in the house I bought some time ago. Previously, these worked independently. However, past few months- the radiators will only warm up if the hot water is switched on which isn't very efficient.

I spoke to a plumber who thinks one of the valves has blown and has quoted me £220 to find the fault and repair it (incl. labour and parts). Is this reasonable? It seems high to be and I have no idea how long it will take (ie split of labour and materials). I have used the plumber before and he was reliable on that occasion. Thank you.

Sounds like your diverter valve has gone.
No idea on cost, but valves are fairly cheap, so that's quite a lot of labour.

Why does it seem high to you ?

What is the cost of the part he is going to replace and how long is it likely to take him if you believe you have a better idea of what the costs should be ? Can you itemise the task list of things the plumber has to do to both diagnose the fault, source the part and replace ?

If anyone is concerned about costs then surely the correct thing to do is a three quote source and see whether you can get cheaper.

If I had a broken divertor valve I could probably fix it myself for less than £50. That's no use to you though, unless you have a clone of me lurking in your basement and have exactly the same central heating system as me.