R-12 Odd-ball Indoor Package Unit

[PalmettoMaintPro]

i am working on a unit that is an INDOOR package unit. The condenser section is ducted with intake and exhaust vents. The evaporator section is open return. They are manufactured by Freidrichs,and their brand name is The Insider. They have a TXV and run on R-22. They are also heat pumps. The units are dated 1999. They are a RPITA to do anything to outside of change the filter. The unit was apparently really popular in Texas,but are now no longer made so any part is going to be aftermarket based on capacity and tonnage. The unit had a refrigerant leak which I isolated and remidied with new compressor at the owners request. the only thing is it had really foamy oil come out when I connected my gauges. i have seen this before but have never asked anyone what this is all about. I was told that someone put R-12 in this particular unit to fill up one of the leak down episodes. Is there any particular method or anything any one can recommend while doing these repairs. Keep in mind that replacement is not an option as I have already went over all the possible catastrophic failures that could go wrong. I had to replace the TXV in this unit too,which was discovered as soon as the replacement compressor was cranked up. This TXV was probally the culprit that took out the compressor.I flushed the lines and the coils thoroughly with rx11 and nitrogen and pulled a deep vacuum. I know some old timers and old schoolers will say "dont flush the coil "But if the flush is purged and vacuumed thoroughly all should be well. I weighed the charge back in according to the rating plate. The pressures are still fluctaiting but not as bad. I plan to remove the filter drier in three days and perform a triple evacuation and recharge the unit and see how it works. Right now even with the dancing pressures it is cooling ok. I just wanted some differing opinions on this.

[bjd]

Wow thats a world of info there, how is the system running after you pulled the dryer?
and which side had the flux in pressure?

[PalmettoMaintPro]

Hey sorry it took so long to get back to the thread. Well since I took the drier off and performed a triple evacuation , the strange old package is doing well. I had to use a small 3/8" liquid drier as my drier due to space constraints. I dont think the drier was as effective as a larger suction drier. The pressures now read 75/325. I know the head sounds high but the condenser exhaust is undersized by a couple of inches which is the only thing I could come up with as all 6 of these things do it even when they havent had the problems this one has. The air is nice and cool coming out of the vents and it is cycling on 95 degree days. So all in all I think it went well . There is still slight flucuation in both sides of pressure though which I believe to be left over nasties in the oil and lines.

[trouble time]

Was the compressor change out like for like? Sounds like the foaming could be caused by excessive oil in the system. IMHO

[bjd]

Very good point Trouble, glad you brought it up.

[PalmettoMaintPro]

That is brilliant Trouble Time .That is a condition I was not aware could exist . I am seasoned but there are I things I have not took time to learn /consider . I love knowledge . I was considering recomending oil removal just am not real sure of the process. But it is not an issue some good research and reading wont cure I am sure

[PalmettoMaintPro]

Quick note the compressor change out was not oem it was aftermarket . THe old model number was copeland scroll with a 26k to denote tonnage, The replacement had 25k as the the tonnage indicator. If I am not mistaken isnt that the way seer is determined? I know the old Rheems/Ruuds used to use 25 in the model number to indicate a higher seer unit. Anythoughts?

[PalmettoMaintPro]

Been getting packed to move to my new house , been super busy . Sorry it has been taking so long to reply guys.