Contsi Posted July 21, 2023 Report Share Posted July 21, 2023 Compressor kicks in blowing not cold air. R12 Low side pressure reads 45 with AC off an drops to zero with AC on. Can't read high side because the fitting appears to be of different size (smaller than low side) so hose won't fit. Anyone know what hose to get for the high side? Standard seem to be 1/4, could it be 3/16 on high side end? Started troubleshooting today and could use guidance along the way. I'll be trying to get the high side reading. I do see Freon through the glass. Thanks Link to comment Share on other sites More sharing options...
Contsi Posted July 22, 2023 Author Report Share Posted July 22, 2023 Found adapter for the high side, hope to get psi reading next Saturday at friends house Link to comment Share on other sites More sharing options...
obsolete Posted July 23, 2023 Report Share Posted July 23, 2023 All my A/C experience is with R134a, but 0psi on the low side with the compressor running says to me that the system is low on refrigerant. Link to comment Share on other sites More sharing options...
Contsi Posted July 24, 2023 Author Report Share Posted July 24, 2023 Thanks for the reply obsolete. My feeling is that you are correct but I'm no AC expert. A few years ago I had the system charged ang got cold air; the following year no cold air so I suspected a leak. So what we were doing on Friday was trying to find the leak but ran into the fitting size issue and could only read the low side. We didn't want to overfill since we couldn't read the high side. Now that I have the adapter, I should be able to get that reading come weekend. Link to comment Share on other sites More sharing options...
GoldStar Posted July 26, 2023 Report Share Posted July 26, 2023 If you took it to a shop to have that recharge done, they most likely used a luminescent compressor oil that should show up under a blacklight. Might be pretty difficult to see now, though. Link to comment Share on other sites More sharing options...
Contsi Posted July 27, 2023 Author Report Share Posted July 27, 2023 A friend who is helping me with the issue has all the equipment to check for leaks, including R12. I just had to pick up some dye. It was not chargerd at a shop previously, another friend who is an a/c guy charged it but we never looked for any leaks. I noticed a couple of greasy spots but hadn’t looked further until now. Link to comment Share on other sites More sharing options...
Recommended Posts