Sonia's Driver

I am repairing the A/C in the del Sol.
I'm replacing the compressor, receiver/drier, expansion valve, and o-rings. Also recharging w/ R-134a rather than the OEM R-12. The system will be flushed in the next week or so.
The system is currently competely discharged. (probably since when the old compressor got a huge crack in it, the scroll disintegrated, and the pressure plate disappeared.

Can someone please confirm whether the condensor fan should operate when the system has low pressure and the A/C switch is in the ON position? According to the wiring diagram for the '93 civic that I was reviewing yesterday, it should not function with low pressure, but that is not the observed behavior, and also I felt rather distrustful of the diagram when I was looking at it. I just though to double-check with the Hynes manual that I have - will do that this afternoon.

Also - should Honda brand PAG oil be used, or is all PAG oil the same?

Thanks in advance.

Former User

I think your circuit diagram for the R12 system is correct. The R134a dual pressure switch needs only 28 PSI (extremely low charge) to close the circuit.

motegicivic

The specs are for R12 (pre 134a) I would not use that as guideline.

Former User

I don't have the R12 pressure switch specs, but the point is that the lower limit of high side pressure needed to close the circuit is quite low for either R12 or R134a Civic systems.

Sonia's Driver

Let me restate my questions in simpler terms:

For the refrigerant pressure switch, (p/n: 80440-SM4-003; SWITCH, AIR CONDITIONING (DUAL) (FUJI)), which was installed in the '93 del Sol, '92-93 Civic, and '90-93 Accord, and the '92 Prelude: is the switch supposed to be closed or open at atmospheric pressure.

I'm asking this because my condensor fan is functioning when the system is open to the atmosphere, and according to the Honda wiring diagram for the Civic, the fan circuit is interrupted by the pressure switch, which would indicate that the switch has failed, or that the del Sol is wired differently.

Thanks in advance for the clarification.

Former User

The switch should be open at atmospheric pressure.

Do a test. Unplug the pressure switch. If the condenser fan still runs, then your Del Sol is almost surely wired like 96-00 Civics, where the pressure switch controls the compressor clutch but not the fan.

cqljohn

to my knowledge, ther are 3 different PAG oils, it all has to do with the volicity of the oil, from Honda all I have seen is PAG 46 and PAG 100. A simple search should tell you what you need to know???

I'm 99.9% all PAG oils are the same as long as you get the correct volicity PAG oil. Honda SP-10 = PAG 46, SP -20 = PAG 100, and so on.....