My guess is that the ambient temperature was between 75 and 80 degrees. Still, I'd like to see the low side a bit lower than that. Keep an eye on it. If the evaporator ices up, it might be a little undercharged.

OP, be aware that those small cans of refrigerant might contain fewer than 12 ounces. The only way to know for sure is to weigh-in each can (or partial can) to arrive at the total amount for your system.

One-quarter cup equals approximately 2 fluid ounces. So, yes, put 2 fluid ounces of the proper weight PAG oil back into the condenser.That's the amount I was going to suggest anyway.

Several questions here, but the first few are:
How did you evacuate it?
How did you charge it?
Did you check for re-heating?

Great news...thanks for updating us.

Both the high and lower pressure switches have been replaced and the refrigerant load is per spec as he had it evacuated and refilled to factory levels. Another thought: Depending on when it was evacuated and re-charged, it's possible that the system has a leak and the refrigerant amount is no long...

Glad that you solved the riddle of the switch/sensor. As for the high and low pressure limits, and presuming that this safety device will be installed on the R/D, they're usually ~405/30 PSI respectively. Above ~405 PSI on the high side, the compressor circuit opens to prevent over-pressurization. B...

In the photo, I can just barely make out the text that says "1.16, Refrigerant pressure sensor signal input, used to protect A/C compressor when pressure drops," and "A/C pressure sensor, +5V, sens gnd, and 0-5V signal" written in by hand. There's also an electrical symbol that s...

tbirdtbird wrote: ↑Fri Sep 16, 2022 8:02 am I take issue with his determination of condenser fan function

Right...it would also be helpful to get actual condenser inlet and outlet pipe temperatures instead of just going by feel to determine how the condenser is performing.

Both the high-side and low-side pressures are too high as previously mentioned. With a low side of ~55 PSI, you are looking at an evaporator temperature of around 60°F, far too warm to provide any measurable cooling. A high side of ~300 PSI, even at 100°F, suggests a condensing issue. You've checked...