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TC_Z's avatar
TC_Z
Explorer
Mar 17, 2018

What is sensor on back of AC compressor?

With your help I am replacing the AC compressor on our 2007 Winn Voyage on Workhorse chassis W24 8.1l engine. There is the electrical connection on the clutch, there are the 2 Freon connections. What is the connection or sensor on the rear of the compressor? And how do you swap it from the old unit to the new?
Many thanks
  • TC&Z wrote:
    Another question, the new compressor came with 2 freon line washers. One washer is thick and one is thin. Odd because disassembling the original its washers are both thin. Anyone know where the thick and thin are supposed to go, or where to look, on the suction or on the discharge? Or did the box have the wrong washers in it? These are shown in the pictorial in the link above but visibly appear to be the same. Thanks


    I contacted supplier and determined that the wrong package of O-rings was in the box. The correct ones are both the same, and both thin, just like the ones I removed. Now back to my repairs....
  • dougrainer wrote:
    I have never seen a OBD-2 connector for a Class-A Motorhome aftermarket AC system. Usually, that sensor is a Hi Pressure sensor and shuts down the compressor power when your Coolant(134a)level gets way low or you lose the 134a. Is this the part you are talking about? Doug

    https://www.ultrarvproducts.com/6571650-A-c-Compressor-High-Pressure-Cut-off-Switch


    Yes! This is the sensor I wasn't expecting as part of the compressor replacement. I wish I had known about this before and I would have bought a new sensor at the same time. Fortunately I am not pressed for time so will order a new one.

    Another question, the new compressor came with 2 freon line washers. One washer is thick and one is thin. Odd because disassembling the original its washers are both thin. Anyone know where the thick and thin are supposed to go, or where to look, on the suction or on the discharge? Or did the box have the wrong washers in it? These are shown in the pictorial in the link above but visibly appear to be the same. Thanks
  • most switches on back of compressor are high pressure they are held in with snap ring very easy to transfer
  • Hope you have the equipment to evac. and charge the system. Also you need to flush system or warranty on new compressor is void.
  • 77rollalong wrote:
    most newer systems have both a high pressure switch, and a low pressure switch. i have seen in some cases where if the low pressure switch trips too many times due to low Freon the body control module will lock out the AC system until the system is charged properly and either have had to manually run a jumper wire to the clutch to the battery so i could put in the correct amount, then clear the code and would run proper after that..


    You are comparing Automotive type control systems with Class A motorhome systems which are totally different control systems. There is NO body control module that affects Class A motorhome AC systems. The Class A AC system is 50 percent Chassis supplied(Compressor/hoses/condenser) and RV OEM supplied(Evap/heater Core/fan motor/Dash control). Doug
  • most newer systems have both a high pressure switch, and a low pressure switch. i have seen in some cases where if the low pressure switch trips too many times due to low Freon the body control module will lock out the AC system until the system is charged properly and either have had to manually run a jumper wire to the clutch to the battery so i could put in the correct amount, then clear the code and would run proper after that..
  • If you are talking about the lock sensor, it should have came with the new compressor already installed. Post a p/# for the old and new compressor and will look it up.

    Most are install when the compressor are put together. If your old system did not have this then you got the wrong compressor if the new one has one. It talks to the engine computer . Here is a link to what it does.

    https://www.yourmechanic.com/article/b1862-obd-ii-trouble-code-climate-control-a-c-lock-sensor-failure-by-brady-klopfer