40's or 50's coke machine

Late 40's machine. Have condenser with no fan. Evaporator has fan. Compressor is new. What pressures should I see after start? I have 23 low side and 250 high. Frost at end of captube, not cool on suck line. Refrigeration not in machine at this time, on service bench. Condenser appears to have a regulator on liquid line. Help please, scott '>

[johnieG]

Hi & welcome, first, what manufacturer is the machine, & what model '>  because regulator & a "cap" tube (capillary tube) on the same machine doesn't make sense to me, can you show some pictures of the bugger? it also depends on which refrigerant it's using, R12/ R134a ( a new compressor might mean it's been converted over to R134a) assuming it's a machine like a Cavalier C51, (convection cooled condensor coil) you're kinda asking us flying blind.... hope we can help...
really need more info!!!

in general, it sounds like it's overcharged. but don't hold me to that...

'>  Thanks for the reply. I am not sure of the machine, as I am doing this for someone else and all I have is the cooling system. It is a Nash-Kelvinator condensing unit part #1068100, using f-12. I have between 6 & 8 oz of R-12 gas installed. It does have what appears to be a regulator on the condenser outlet, just before the capilary tube. Today I started it up with 85*f ambient.Suction was 10#, discharge 130#. After 30 minutes it settled out at 34# suction, 250#discharge. The compressor is a new Tecumseh #AE160AL-727-J7  labeled R-12. Typical water cooler style I believe. I am concerned about the thermal overload and compressor in general being up to the task. '> Scott

'> How come it got so quiet?

[Jim]

Well...
For expert advice, we all depend on Eric at Global Compressors who drops in from time to time...

[globalcompressors]

Hi Scott,

You've said a couple of things that may have thrown us off.
One, you said no condenser fan. Does that mean there is not one and is a "static cooled condenser" or is the motor missing? Second, you also said "water cooler style". Do you mean the box being a water bath or are you speaking of the compressor itself? It would really help if you had a little more info of maybe a photo or two. From the pressure readings you have given, it sounds like it maybe a bit over charged or too large of a compressor. Of course that could change depending on what freon is being used. There will be different properties as well as pressures. If the compressor is too large, you will see a lower suction pressure as well as a higher head pressure. If you try adding more freon, to bring up the suction pressure, the head can easily exceed 250 or 300 psi. The compressor is not designed to run that high. See what you can come up with and get back to us.

Eric

'> As it turns out, the compressor is in fact too big. I was given a 5th hp in place of an 8th hp compressor, with the pressures doing exactly as you say. Also, it is a static condenser, upon which we have added a small fan. Should I remove this. We have ordered the 8th hp compressor. The refrigerant is r-12. The charge I am trying is 10oz. The machine is a V-39. Sorry  about lack of info, I will try and do better. Scott