Wilo Yonos Pico pump - gurgling sound

[pingo123]

Hello

My pump makes an odd sound... see attached file. Is this normal? Tried venting/bleeding it but no difference. Same sound whether the hot water or CH is on. Changing the pump speed doesn't help.

Thanks

Chris

 

[John.g]

If you have a open vented system ensure header tank "full", if a closed system with expansion vessel ensure system pressure at 0.75 to 1.0 bar which I'm sure you have.
Can you try and vent the pump with the discharge valve closed and then try and vent it through the 1.5 ins connection to the pump body discharge, that should ensure that you have a flooded pump then suggest constant pressure mode at 3m setting. With a closed discharge and pump properly flooded/vented the power should be ~ 12W and should increase on opening the discharge valve.

 

[pingo123]

If you have a open vented system ensure header tank "full", if a closed system with expansion vessel ensure system pressure at 0.75 to 1.0 bar which I'm sure you have.
Can you try and vent the pump with the discharge valve closed and then try and vent it through the 1.5 ins connection to the pump body discharge, that should ensure that you have a flooded pump then suggest constant pressure mode at 3m setting. With a closed discharge and pump properly flooded/vented the power should be ~ 12W and should increase on opening the discharge valve.

Thanks for all your input, will give it a go.