Many thanks for your time and patience.
Installed a new thermostat this morning. The AC compressor clutch no longer cycles, engaging and disengaging, when the AC switch is off.
However, when the AC is switched on the cycling restarts, at least at idle, not noticeable when driving.
I only have a low DIY filling kit with low pressure gauge so did the best of a bad situation and connected it up. Low side, at 12C (54F) with the AC on 20/25 Psi, and then when the clutch disengaged it went up to 40/45 Psi. This seems normal? I should add I have never recharged the AC on this car.
When test driving with the AC off, the heater seems noticeably cooler, unless turned full on when it is really toasty. The old thermostat was reluctant to open early so maybe a bit of over-temperature.
Got some technical info for the car off the web which seems to support what you say. It states:
- â€ Compressor Energy Conservation Control. Optimum ON/OFF control of the compressor is achieved according to the outside/inside air mode air temperature (air temperature sensor), and insulation.â€
- â€ Detection Control For Refrigerant Leaks. When it is judged from the air temperature (air temperature sensor) and the refrigerant pressure (A/C pressure sensor) that the refrigerant amount is the specified value or less, or the refrigerant pressure is abnormal, the compressor is forced to be cut off to protect the A/C system.â€
What next please?
Sunday, February 23rd, 2020 AT 2:03 PM