Central Heating Pump High Pitched Noise All aspects of plumbing questions and answers, help, tips and information

[Robh1990]

Hi guys I've got a DAB Evosta central heating pump and lately its been making a high pitched squealing kind of noise which travels through most of the heating system. I've turned the bleed screw and doesn't seem to be any air in there. Bled all the radiators.
Any ideas, I'm grateful.

[stoneyboy]

Hi Robh1990,
Sounds like you have air in the pump - you need to remove the central bleed screw completely to clear the air, have a cloth ready to catch the escaping water.
Regards, S

[Robh1990]

Hi Robh1990,
Sounds like you have air in the pump - you need to remove the central bleed screw completely to clear the air, have a cloth ready to catch the escaping water.
Regards, S

Turn the pump off first? Do I need to close off the water either side of the pump? Or just open the screw until it runs dry?

[stoneyboy]

Hi,
Probably better with the pump running and valves open.
Water should come out around the pump shaft once the air has cleared.
S