Air in the system or not?

[rossi]

Ever since a handyman changed our leaking valve in our radiator upstairs to a thermo control valve, loud bubbling noises (air stopping water to pass by) can be heard whenever the central heating system is started. I've bled all raditors and it makes no difference.

Please help because i'm now running out of ideas.

 

[AlanE]

Personally I would suggest calling in a proper heating engineer and have the problem sorted properly.

A bit more expensive than a handyman but then you get what you pay for as you have found out.

Alan

 

[MANDATE]

The system I assume would be drained so try bleeding the pump as well.
You may have to bleed your radiators more than once to ensure all the air has been removed from system.