Noise diagnosis?

[Doctorflip]

I have a fully pumped system using a glow-worm micron 70FF. It has a divertor valve near the pump. If the valve is set to o.3 bar you get good performance but as the system switches off a loud knocking noise occurs. If I alter the valve setting I can get rid of this but takes longer to heat the radiators. Anyone got any suggestions as to the ideal setting or could this be related to a specific fault.

Thanks

Doc

 

[ollski]

do you mean an automatic bypass valve linking the flow and return after the pump and before the motorized valve/s?

 

[Doctorflip]

Yes I think that is the valve you mentioned, it is a big brass valve with a plastic screw top with a scale marked in bar. The lowest setting is 0.5 and the closer the reference mark is to this the more noise I get. To be honest I'm not sure what this valve actually does. Thanks very much for taking the time to comment.

Bob

 

[oilman]

The valve is there to provide a path for the water if all the other valves are shut. What happens if you set it to a higher figure?

 

[Doctorflip]

If I set the valve higher I get less noise but it takes much longer to get any heat in the system which seems very inefficient, I was wondering what would happen if I closed the valve off completely but I'm a bit apprehensive I might damage the system.