Short Cycling

[ferret82]

Hay everyone,

I have this problem with a Freezer unit.

In normal operation the the unit will cut in at -18C and cut out at -20C.

Here is my problem when the temp is -20C and the unit is supposed to be cutout until the temp is -18C but it short cycles a few time until the temp is -18C then a solenoid opens and the compressor starts pulling the room back down to -20C

I noticed that the solenoid on the outlet side was just frosty and when touched the inlet and outlet of the solenoid the inlet was warm and the outlet was cold.

Could this mean that the seat in the solenoid is not seated properly as there is some refrigerant bypassing which is causing the unit to short cycle during the period it is supposed to be off.




thanks

[sedgy]

hi ferret 82, it sounds like there is something on the seal on the solinoid valve, so when its closed there is gas leaking through, it needs pumping down strip the valve down clean out, maybe fit a liquid line dryer, + there you go

[frederik79]

is the valve far away from the exp valve ?

[taz24]

Hay everyone,

I have this problem with a Freezer unit.

In normal operation the the unit will cut in at -18C and cut out at -20C.

Here is my problem when the temp is -20C and the unit is supposed to be cutout until the temp is -18C but it short cycles a few time until the temp is -18C then a solenoid opens and the compressor starts pulling the room back down to -20C

I noticed that the solenoid on the outlet side was just frosty and when touched the inlet and outlet of the solenoid the inlet was warm and the outlet was cold.

Could this mean that the seat in the solenoid is not seated properly as there is some refrigerant bypassing which is causing the unit to short cycle during the period it is supposed to be off.




thanks

It could be the valve, you need to pump it down and strip the valve down and then see if the seat is damaged or being kept open by swarf or somthing.

It only takes a few mins to strip so check it.

taz.

.

[coolhibby1875]

the fact you have frost when the valve is de energised shows its passing, Pump the unit down clean/replace guts of valve change your drier and you will be good as gold!