Potterton combi 80 hot water but no heating....HELP!!!

by **opfresco** » Thu Dec 04, 2008 2:42 pm

My Potterton combi 80 boiler provides hot water but when heating is called for, boiler fires up for 1-2 minutes then shuts down. Pump and fan are both running. This "on -off" cycle happens every 30 mins or so (if the boiler is on "constant" or on timer).
Please help! It's cold in Scotland.....

by **gasmick** » Thu Dec 04, 2008 9:17 pm

hi it sounds like it may be the C H temp thermsitor but to check it out the combustion cover needs to be removed but thats illegal for D I Y
and must only be attempted by a competant person so get a corgi engineer to look at it

by **htg engineer** » Fri Dec 05, 2008 8:32 pm

Possibly diverter is stuck in HW mode, as there's no taps running the heat cannot escape therefore the boiler will keep cycling on and off.

htg