Post by coldspaces on Oct 24, 2016 0:52:25 GMT
I really should stop looking at Cragslist. Last Sunday I drove about 20 miles each way and adopted this Frigidaire charged with Dichlorotetrafluoroethane. Was advertised as needing a compressor. The PO said he rewired it 20 years ago and it had been starting funny for a long time till it stalled completely. He tried a NOS start relay but still no start. Got it home and hooked up the Annie and the compressor started right up so I hooked it back to the wiring and tried it again. Tripped the breaker as soon as I plugged it in. Turns out the light has never been rewired and is now unhooked.
Since these run the low side in a vacuum the charge fitting (On suction line) had been soldered over and I had to remove the solder to put on the charge adapter. I forced in some Supco 88 thinking the problem was a sticking compressor but found that it would still stall. After trying it for hours I decided it would always start if it was balanced out so something else was going on. If left running long enough to warm up good it would stall every time and only a small part of the evap would frost.
The next day I ran it some more and decided that the problem was that the system was wet inside and ice was restricting the cap tube. Didn't realize it at first as I always heard some refrigerant flowing into the evap when I listened.Then I heard the flow into the evap stop completely and I knew there was water inside. I then warmed the tube at the end of the cap tube and the flow came right back.
I have no new r114 so I had to recover what I had and hope to reuse it. After recovering the juice I pulled a vacuum for a while and then charged it to 75 psig of dry nitrogen, factory test pressure was 100 psig. I let this set about 20 hours and it held right on 75 psig. At this point I installed a new drier with hi pressure tap and pulled what I thought was a good vacuum. I then charged it with the old gas and tried it again. I could still only get a small part of the evap to frost and after trying to improve it I decide the evap must be oil logged and need more R114 to get it to move. I know I lost some of the charge I recovered so I must still be low right?
Well the only source of 114 I have is another Frigidaire that I think has a plugged strainer that will be a bit tricky to replace and this has a poorly done repaint so here I am making a transfusion from it. I would add a little gas and warm the evap but all I got was a bit more coil frosted and a compressor that stalled repeatedly if left run. At this point I had previously unhooked the hi pressure gauge and was trying to avoid hooking it back up and losing anymore 114 that I had to. Finally I heard the flow stop completely again and I knew there was still water inside.
I did not want to start over again only to find out the compressor was bad after doing the work twice so I made some adapters, hooked up the hi pressure line and flowed the refrigerant through a drier in the gauge hose. It took a while but I started to get more flow. Still the compressor would stall every time if left to run. I shut it off for the night and left the low pressure side exposed to the extra drier all night.
The next day I was getting enough flow to frost all the evap but she still stalled out. I finally decided that when the cab tube was restricted I had sucked too much juice from the other unit and the poor rotary compressor was stalled because of excessive head pressure. 105 Psig did not seem like much till I remembered the PT chart shows r114 at 50 psig when at a 120 F temp. I ended up bleeding 5 oz into the recovery tank and she has been purring along for a day and 1/2 now and maintaining 34-35F. I really did not think I was going to get this one working.
Since these run the low side in a vacuum the charge fitting (On suction line) had been soldered over and I had to remove the solder to put on the charge adapter. I forced in some Supco 88 thinking the problem was a sticking compressor but found that it would still stall. After trying it for hours I decided it would always start if it was balanced out so something else was going on. If left running long enough to warm up good it would stall every time and only a small part of the evap would frost.
The next day I ran it some more and decided that the problem was that the system was wet inside and ice was restricting the cap tube. Didn't realize it at first as I always heard some refrigerant flowing into the evap when I listened.Then I heard the flow into the evap stop completely and I knew there was water inside. I then warmed the tube at the end of the cap tube and the flow came right back.
I have no new r114 so I had to recover what I had and hope to reuse it. After recovering the juice I pulled a vacuum for a while and then charged it to 75 psig of dry nitrogen, factory test pressure was 100 psig. I let this set about 20 hours and it held right on 75 psig. At this point I installed a new drier with hi pressure tap and pulled what I thought was a good vacuum. I then charged it with the old gas and tried it again. I could still only get a small part of the evap to frost and after trying to improve it I decide the evap must be oil logged and need more R114 to get it to move. I know I lost some of the charge I recovered so I must still be low right?
Well the only source of 114 I have is another Frigidaire that I think has a plugged strainer that will be a bit tricky to replace and this has a poorly done repaint so here I am making a transfusion from it. I would add a little gas and warm the evap but all I got was a bit more coil frosted and a compressor that stalled repeatedly if left run. At this point I had previously unhooked the hi pressure gauge and was trying to avoid hooking it back up and losing anymore 114 that I had to. Finally I heard the flow stop completely again and I knew there was still water inside.
I did not want to start over again only to find out the compressor was bad after doing the work twice so I made some adapters, hooked up the hi pressure line and flowed the refrigerant through a drier in the gauge hose. It took a while but I started to get more flow. Still the compressor would stall every time if left to run. I shut it off for the night and left the low pressure side exposed to the extra drier all night.
The next day I was getting enough flow to frost all the evap but she still stalled out. I finally decided that when the cab tube was restricted I had sucked too much juice from the other unit and the poor rotary compressor was stalled because of excessive head pressure. 105 Psig did not seem like much till I remembered the PT chart shows r114 at 50 psig when at a 120 F temp. I ended up bleeding 5 oz into the recovery tank and she has been purring along for a day and 1/2 now and maintaining 34-35F. I really did not think I was going to get this one working.
