boiler problem

[pjmanch]

i have a potterton promax system32 he plus, it has an internal pump and expansion vessl, it is piped using a mid position valve system, when running the return does not get hot, i have checked for blockages and air locks, i have also changed the pump but still cold return, is there something like a stat on the boiler which could be faulty which is telling the boiler it has reached temperature, any clues

 

[Puddle]

Sorry am missing something here, you say return does not get hot, does flow get hot, do some rads get hot ,is boiler operating at all or firing and then going out, with a bit more info ,hopefully we can help
🙂

 

[pjmanch]

Sorry yes, the flow gets hot and the boiler goes through the correct sequence of cutting out when it reaches the selected temperature
And fires again when the temp drops. Radiators on hot on flow side, cheers

 

[justlead1]

Hi It best to follow some sort of sequence when fault finding. Just try turning heating off and make sure cylinder is calling for heat. After a few minuets the return should warm. If not try manual setting of mid position valve and so on. This method will point you in the right direction.

 

[pjmanch]

ok thanks i will give it a go although i have tried something similar and still had a cold return