Post by 100yearfridge on Jan 8, 2017 18:35:53 GMT
A little update. I have been running back and forth to Kevin's every week or so to get this little thing running right. The neoprene washers were a great suggestion; the kit seals up much better. We put a fresh charge of r12 in it and everything was looking good until we ran out of gas. The thermostat cycled, and when it kicked on again, cooling was next to nil. I think it was working well while we were charging into the compressor shell because compressor was getting a good feed of refrigerant and was able to achieve a liquid plug on the inlet of the cap tube. Once the machine cycle, and I was out of gas to feed it, the liquid plug never happened and it was just circulating gas. As it turns out we were just short on gas, so Kevin got another two cans for the following week.
The following week we resumed charging, and again everything was looking good. It cycled a few times and still good. We had mentioned to each other that we shouldn't get our hopes up as this has happened before. Then when I pulled the charging adapter off and it cycled again cooling was poor once more. I put my thumb over the GE charging port and got a burp. The bristol valve was not seating well, and the hex cap seal was long gone. Kevin went to the hardware store to get o-rings to try in the hex cap while I pulled the charge. I removed the bristol valve from the service port and cleaned it off. Doing a nitrogen pressure test, I still got a tiny burp from putting my thumb over the port. We re-charged until operation was decent, then the compressor started to growl like it was low on oil. This was extremely unnerving. I wrapped up all my equipment and told Kevin I was bringing the unit back to my lab to do the work properly. The rack we made to support the unit, evaporator and all, transported well.
Hindsight is usually 20/20. I certainly wish I had this unit at my place when we started, but was hoping that a simple squirt of refrigerant charge would suffice. No such luck. These old units, along with the service valve kits, need special attention made to the seals. I should have known better, but here we are. Now that I have it in a nice temperature regulated environment where I can do longer term pressure tests on everything, I can feel much more confident in the work.
I want to get that metal ring off the high side port so i can perform a strong evacuation on the high side. If it comes to it, I'll put schraders on it to make things a little easer. It's likely that I'll be adding compressor oil, or more likely changing it, so figuring out the capacity is a priority. I'll be reviewing the flat top manuals for clues. We don't have a manual. Attached some pictures.
The following week we resumed charging, and again everything was looking good. It cycled a few times and still good. We had mentioned to each other that we shouldn't get our hopes up as this has happened before. Then when I pulled the charging adapter off and it cycled again cooling was poor once more. I put my thumb over the GE charging port and got a burp. The bristol valve was not seating well, and the hex cap seal was long gone. Kevin went to the hardware store to get o-rings to try in the hex cap while I pulled the charge. I removed the bristol valve from the service port and cleaned it off. Doing a nitrogen pressure test, I still got a tiny burp from putting my thumb over the port. We re-charged until operation was decent, then the compressor started to growl like it was low on oil. This was extremely unnerving. I wrapped up all my equipment and told Kevin I was bringing the unit back to my lab to do the work properly. The rack we made to support the unit, evaporator and all, transported well.
Hindsight is usually 20/20. I certainly wish I had this unit at my place when we started, but was hoping that a simple squirt of refrigerant charge would suffice. No such luck. These old units, along with the service valve kits, need special attention made to the seals. I should have known better, but here we are. Now that I have it in a nice temperature regulated environment where I can do longer term pressure tests on everything, I can feel much more confident in the work.
I want to get that metal ring off the high side port so i can perform a strong evacuation on the high side. If it comes to it, I'll put schraders on it to make things a little easer. It's likely that I'll be adding compressor oil, or more likely changing it, so figuring out the capacity is a priority. I'll be reviewing the flat top manuals for clues. We don't have a manual. Attached some pictures.