Central heating comes on in summer

[helenw@bfbs]

Hello Even though my timer is switched to 'off all the time' and my wireless thermostat is down at 15 for good measure, my rads keep getting hot, even when it's 26C outside. I have a combi boiler - could it be a fault with the diverter valve, or more likely a wiring problem with the timer? Help - I'm roasting alive!

(Edited for awful typing)

[ethandron]

my son had the same problem. the engineer told him it is a known problem with combi boilers. apparently when you've been running the hot water tap, and then turned it off, the boiler sometimes 'dumps' the warm/hot water into the heating system. the only way round it is to turn off your radiators.

[helenw@bfbs]

Thanks for that. My plumber has just phoned me with the price for a new diverter valve, and I think I'm going to give it a go and see if it solves the problem. If it does, I'll let you know and you can tell your son!

[ethandron]

that would be good, thanks. and the price the plumber charges too. if it's too pricey i think he'll just turn the radiators off.

[helenw@bfbs]

He's told me the part is �120 plus VAT, and then there's an estimated 2 hours labour. Worth it if it works...

[ethandron]

think my son will stick to just turning the radiators off for now, as he has better uses for maybe �200 at the moment! hope it works and thanks for the info.

[helenw@bfbs]

Just to let you know, I had the diverter valve replaced and it completely fixed the problem! Definitely worth the money to get rid of the stress and exasperation of constantly having the radiators hot at random times! My plumber said my type of combi boiler regularly fires up the heat exchanger so that when you ask for hot water from the tap you don't have to wait too long for it to heat up. And whenever that happened, I got hot rads. If your son doesn't want to spend the money, just make sure he leaves one rad on as a sort of safety valve.