pump bleeding

[hotncold]

hi all.
just a couple of questions on bleeding a vented system with a Grundfos pump.
Can you bleed the pump with the system running ie remove the big chrome nut? The reason I ask is that the service engineer did just that yesterday but looking at all the threads it don't look correct.

also a manual air valve at the highest point (just above the boiler on my system) should it be opened with the system on or off?

 

[HarrogateGas]

Yes you can bleed the pump with it running...in fact its the best way of doing it..have a towel underneath it though.

 

[hotncold]

Thanks for that Harrogate
would that be the same with the man. air valve above boiler. ie can u vent with system on?

 

[HarrogateGas]

no the only blled point you can really vent with the pump on is the pump itself. Is does depend on what system you have and the way it is confugured but ts you blled all vents with the pump off you wont be wrong.

The bonus of bleeding the pump with the pump running is that it vents a lot of air being pulled through the pump, not just trapped in the pump itself.

 

[hotncold]

thanks again