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View Full Version : old r12 walk in freezer won't drop below 3*.



jasonrd
05-08-2014, 08:48 PM
Sight glass is clear. Superheat at compressor is 20*. Both coils clean. It's an old semi hermetic, I thought the valve plate was bad. Changed out the valve plate expecting a super efficient compressor, but got no improvement. Not familiar with r12, I think the suction was at like 12 psi, witha bout 10* box temp. The damn thing runs and runs.

The MG Pony
06-08-2014, 06:12 PM
What state is the condensor at?, what is the ^t on the filter dryer?

TXV or Cap. so much info missing here

nike123
06-08-2014, 08:23 PM
Superheat at evaporator? Frost pattern at evaporator?

Brian_UK
06-08-2014, 10:11 PM
Why are you working with/on R12 ????

monkey spanners
06-08-2014, 10:25 PM
Door seals? cold room panels ok?

palmerm
09-08-2014, 11:09 AM
Sight glass is clear. Superheat at compressor is 20*. Both coils clean. It's an old semi hermetic, I thought the valve plate was bad. Changed out the valve plate expecting a super efficient compressor, but got no improvement. Not familiar with r12, I think the suction was at like 12 psi, witha bout 10* box temp. The damn thing runs and runs.

What head pressure do you have?

install monkey
09-08-2014, 04:09 PM
you sure its a freezer, not a fridge:o

hyperion
09-08-2014, 05:28 PM
How long has the box been offline? What is the insulation like? If it has completely thawed and then the insulation has got wet, it will take a long time to re-freeze the insulation. As it was designed for R12 and is therefore probably quite old, you would be lucky to get down to 3degF or are you meaning 3degC? What are the suction and head pressures, is it fully or over charged. Have you got any restrictions at the drier?

The MG Pony
09-08-2014, 08:28 PM
One hit wonder, think it safe to say no need for futur rplies here till they can be bothered to post above stated data.