Worcester Heatslave 20/25 Scalding hot water & no heating

[winnart]

Hi,
I have a Worcester Heatslave 20/25 oil boiler which is about 10 years old. Even though the hot water thermostat is turned right down, the water is piping hot. The central heating only works now & again. An engineer replaced the Diverter valve control box I think, he said this was also causing the problem with the hot water. He didn’t replace the spring as he said this seemed OK. I have called him back but I live on the Isle of Man so it could be a long time before he returns, so I thought I’d try to find a solution myself. I’d appreciate any advice you can give. Thanks

 

[lame plumber]

if he only replaced the diverter valve head, then the valve itself is probably seized and needs a whole new unit now as the head will have burnt out again. Good luck doing it yourself, little beggars as as soon as you move one bit another will start leaking, so be careful, you may wish you never started

 

[winnart]

Thanks for your advice, I think I'll just wait for the engineer to come back, but it is nice to know what was causing the problem. I have a better understanding of whats going on.