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onebad4D
07-16-2011, 01:38 PM
The factory service manual says our vehicles are equipped with a "Low Pressure Switch" that cuts off the compressor when the high pressure side drops below 28psi. It doesn't mention cutting off when the pressure gets too high. Does anyone know when Honda first started installing "Dual Pressure Switches" to deal with abnormally low or high pressures?
Sprocket
07-17-2011, 06:00 PM
Good question! I was sitting at a stoplight for 5 minutes on a 100 degree day. All of a sudden smoke's coming out of the hood. Pop the hood and all my refrigerant and oil is spewing out at the receiver-dryer. Does this mean that my car only has a low pressure switch which can't detect when the pressure's too high? How can we tell the difference between a dual pressure switch and a low pressure switch?
Oldblueaccord
07-25-2011, 07:26 PM
The low pressure switch is on the low side on the compressor not the high. I would think you would need to tap into the high side some place if there is such a switch on Hondas. have you looked up the part number by year ?


wp
Oldblueaccord
07-26-2011, 03:20 AM
The low pressure switch is on the low side on the compressor not the high. I would think you would need to tap into the high side some place if there is such a switch on Hondas. have you looked up the part number by year ?


wp

http://www.autopartswarehouse.com/details/QQHondaQQAccordQQ4-SeasonsQQA-fs-C_SwitchQQ19861989QQFS20926.html

I am surprised but it seems it is a hi/low switch combined.

wp
onebad4D
07-27-2011, 12:29 PM
The low pressure switch is on the low side on the compressor not the high.


wp

The factory service manual on page 23-2 states: "LOW PRESSURE SWITCH: interrupts current to compressor clutch when HIGH pressure drops below 28 psi" Said "Low pressure switch" is located on the high pressure side.




wphttp://www.autopartswarehouse.com/de...QQFS20926.html

I am surprised but it seems it is a hi/low switch combined.
wp

Yes, today in 2011 they are dual pressure switches. The real question is: what was installed on the assembly line back in 1988? Was it just a low pressure switch like the service manual shows or was it a dual pressure switch?