single door reach in freezer

[bernie]

r-12 system, remote condersor, lac-4-100, gfe-1\2-zp valve.
175 psi head pressure, 0 psi suction pressure. one thing for sure is the lac-4-100(condensor flood control is working properly. outside temp is 55 degrees and box temp is high 80's. Distributor tubes are all frosting equally.
Ant thoughts on this subject are welcomed. were trying to fix this one from 100 miles away. thanks

[subzero*psia]

One fact can be seen immediately... you have a 128 degree condensing temperature while the outside ambient is only 55 degree's (fahrenhiet). The suction is slightly low but not too far out... it shouldn't be since it is a modulating valve.

With the high head, you could be seeing air in the system or condenser coil blockage.

What is this freezer used for... if the evaporator was subjected to a very high heat load you may have crankcase oil in the condenser coil creating a blockage. This oil will eventually make it to the evaporator and low evaporator pressure will develop... if the system survives that long.

I have to admit I am not sure of what you are describing as a condenser flood control? Also, why would the end-user need this device?

[Gary]

This is the minimum data needed for long distance trouble shooting:

High side saturation temp.
Condenser air in temp.
Condenser air out temp.
Liquid line temp at receiver outlet.
Liquid line temp at TXV inlet.
Low side saturation temp.
Evaporator air in temp.
Evaporator air out temp.
Suction line temp at TXV sensing bulb.
Suction line temp near compressor inlet.

It is also the minimum data needed for short distance trouble shooting.

My guess (and guessing is all we can do without data) is also non-condensables.

[Gary]

The first thing I would do is shut down the system and see if the equalized saturation temp matches ambient temp.

[Gary]

Given the very high head pressure, if there are non-condensables (air) in the system, the equalized saturation temp will be well above ambient temp. If this is the case, I would be looking for a substantial low side leak.

If the problem is not non-condensables, then the flood controls and/or overcharge goes to the top of my list, although I would be wondering why the evap coil isn't feeding. Possibly a combination of problems. Unlikely, but not impossible.

[bernie]

thanks for the tips, were taking a road trip tomorrow
to rap this dilema up, as always ill keep you posted as to my findings.

[bernie]

still havent gone to to fix this freezer yet. I wonder if the ice cream is still frozen

[subzero*psia]

how it all turns out.

[bernie]

oops, turns out they couldt wait any longer and called in a brand x company to fix the freezer.
Guess this answers my previous question.
Win some , loose some. Actually im relieved, its been middle 90's
her all week, were very busy.
Sorry such a let down, I know we all wanted to here the end of the story

[Abe]

-------------------------------
High side saturation temp.
Condenser air in temp.
Condenser air out temp.
Liquid line temp at receiver outlet.
Liquid line temp at TXV inlet.
Low side saturation temp.
Evaporator air in temp.
Evaporator air out temp.
Suction line temp at TXV sensing bulb.
Suction line temp near compressor inlet.

It is also the minimum data needed for short distance trouble shooting
---------------------------

Gary, I need an education. Assuming we collect all this information, how would you then use to find the problem

I know Im asking a pretty stupid question here, but is there a standard program where you input all of this data, say into a computer, and it then list exactly what the operating parameters, conditions should be for a given situation.

If there is such a program, what a boon it would be, This wouldnt of course take us away from standard procedures using our hands/fingers to take temperature measurements !!! (techs aghast) murmering, thinking, prodding, and looking for solutions, even escaping for a crafty cigarette.

Software which could run on a Psion , and software written by manufacturers could be great

Im intrested to learn how you use the information, once youve taken all the recordings of temperatures and pressures to come to a prognosis

[Gary]

As a matter of fact, I have two such programs, one for refrigeration and the other for A/C, which analyze this data (and more), and tell you what's wrong with the system.

[Abe]

Gary

I am intrested in purchasing these programs. Would you mind directing me to the supplier?
Thx

[Gary]

I am the supplier. Use the link after my name.