City Multi - Inverter Speed / Noisy Check Valve

[Contactor]

:)Hello

Have a noisy check valve on a new PURYP250YHMA whenever the compressor speed dops below 50hz. Having discussed briefly with Mitsu tech and Thermatech (thanks again) it seems there is a dip switch setting which will increase the speed to a minimum of 30hz.

I have had a look through the green Mitsu City Multi service handbook and cant find anything listed for SW2-5.

Any thoughts anyone?

Many thanks :p;):D:o

[no-ri-ta-n]

try sw3-1 on

[desA]

Out of interest:

In what orientation does the check valve lie?
Is it horizontal, angles, or vertical?

Where is it positioned - the discharge line?
How close to the compressor, or condenser?