I hope I'm not becoming a bother in this forum, just trying to learn as I go. I'm working on an old commercial reach in, mostly just for fun at this point. I have a gauge on the low side as there is no high side port, the unit should normally run at 22psi low side, but this unit is continually dropping in pressure as it runs. It will stay at around 10 for a while, but once the condenser fans kick on the pressure sky rockets up into the 50psi range, the compressor shuts off on the overload shortly after this happens. Any idea what's going on. Not sure if its low on refrigerant, partially restricted or if something else may be going on. At this point I've pretty much lost hope in getting anyone else to come look at this thing. There doesn't seem to be anyone in my area that works on them. So I'm on my own.
Sudden pressure increase
AMF Mechanic
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I hope I'm not becoming a bother in this forum, just trying to learn as I go. I'm working on an old commercial reach in, mostly just for fun at this point. I have a gauge on the low side as there is no high side port, the unit should normally run at 22psi low side, but this unit is continually dropping in pressure as it runs. It will stay at around 10 for a while, but once the condenser fans kick on the pressure sky rockets up into the 50psi range, the compressor shuts off on the overload shortly after this happens. Any idea what's going on. Not sure if its low on refrigerant, partially restricted or if something else may be going on. At this point I've pretty much lost hope in getting anyone else to come look at this thing. There doesn't seem to be anyone in my area that works on them. So I'm on my own.
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This should be posted in refrigeration and ice. And keep asking questions.
Why is the condenser fan not coming on with the compressor?
There is no normal suction pressure per say! with R-12, 134A your looking for around 16#'s at or near temperature but that's not gospel.
Few even have low side access, when we have to access the system I install this
Why is the condenser fan not coming on with the compressor?
There is no normal suction pressure per say! with R-12, 134A your looking for around 16#'s at or near temperature but that's not gospel.
Few even have low side access, when we have to access the system I install this
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My mistake, I meant to say evaporator fans. The unit is a continental 2f. Charged with 404a.
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Helps to let us know that from the biging.
Freezers delay the fans from starting when the evaporator is above 25°F (coming out of defrost they will blow water off and that refreezes) The reason your pressure increased was the warming of the coil.
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Low side shoots up to 50 ... from 10 ?
Are the defrost heaters staying on ?
Are the defrost heaters staying on ?
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Depending on the op box temp 50psi is around 18* so possible normal operation. he’s not giving us a complete picture
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