Walk in Solenoid noise

[chince13]

Installed a walk in freezer last week and the customer has asked to make into a cooler instead. (Unit had been used in another location prior to this installation)

Ive had a few problems changing unit freezer over to cooler,

Found unit was pumping down due to a restriction at solenoid inlet (piece of rubber).
Removed restriction and opened valves after evac and then removed timer pins and wired evap fans so I wouldn't have a fan delay on start-up.


Run tested unit to see if it would shut off on thermostat A419 johnson controls.
When stat satisfied solenoid would start bouncing making a racket, removed wires from solenoid ohmed out, checked to ground it's fine electrically with full 240v during call for cooling. But once the thermostat was satisfied and closed it would bounce and rattle until i brought the temp down to call and open solenoid.

Ive opened solenoid a few times and flushed LL with nitro to clear any debris.

Im thinking maybe seat of the solenoid valve is gone and compressor is forcing liquid through a slighting opened seating of the valve.

Any ideas?

[Tommy knocker]

Does it pump down? I'm guessing not. Your probably on the right track.

[chince13]

Does not pump down. I'm guessing that it is attempting to once stat has satisfied.

[Phase Loss]

its backwards

[cool_tech_llc]

Found unit was pumping down due to a restriction at solenoid inlet (piece of rubber).

>First warning sign - any more rubber/debris still floating around?

Ive opened solenoid a few times and flushed LL with nitro to clear any debris.

>As above - if chunks are stuck between needle and seat the nitrogen may not be able to flush it through the valve.

Im thinking maybe seat of the solenoid valve is gone and compressor is forcing liquid through a slighting opened seating of the valve.

>inspect needle/seat/spring and if that's not it check what Phase Loss said and make sure it's installed with the right flow direction.

Any ideas?[/QUOTE]

[chince13]

Yes it's installed correctly with spring seat and needle in correct position and facing installed in the right direction.

[ar_hvac_man]

its backwards

backwards or trashed. stick a new one on there

[chince13]

Changed out solenoid. Stop the banging then found TXV screen had disintegrated im guessing from what ever was floating around in system and had caused restriction in TXV causing it to pump down. Sigh.

Had an hour and a half drive to supplier then back downtown at 3pm
Replaced and were off to the race's.

[fridg]

Have seen this on small cabinet freezers , from manufacture new solenoid hammering hot gas to coil , spring tension on danfoss valve incorrect , hence not seating correct.