Air in pumped central heating All aspects of plumbing questions and answers, help, tips and information

[Faff]

I have a pumped central heating system that continually draws air in through the vent pipe. (the pipe that drops down into the top of the header tank)

I was thinking a good solution is to extend this pipe so it sits below the water level in the header tank.

Is this a good idea, or not?

[parkyplumber]

this is a bad idea as you are effectivley sealing your heating system from the atmosphere. Its called an open vent for a reason.
The pump may be sited in a bad position related to your cold feed or vent pipe

[htg engineer]

No, you could try extending the vent, it should go to 18" above the tank.

Is this a new problem ? or has it always been the case ?

Pump speed and position may be to blame.

htg

[Faff]

Thanks guys, I will definitely give that idea a miss.

The problem has been there since I moved in about 2 years ago.

I'll check the height of the vent and reduce the pump speed. If that doesn't work I'll get someone in to take a look.

Cheers