boiler problem

[shuttlebasher]

can anyone please help i have a potterton neataheat 16=22 and recently having problems the heating and water will work fine then all of a sudden the loft will fill with steam from the expansion pipe to the header tank the water in the header tank is then hot! any ideas please

 

[Puddle]

possible boiler thermostat faulty/out of calibration,causing over heating of water in system 🙁

 

[shuttlebasher]

cheers for that at least i wont need a new boiler yet!

 

[oldplumber]

No but you will need a new ceiling if you dont get it fixed pronto