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Hello,

My 2012 Volvo XC60 has had intermittent AC problems since March of 2018. At that time, my mechanic diagnosed a failing AC Pressure Switch and put in a new one. The part was not an official Volvo switch because they are no longer available. In March of 2019 my AC had the same intermittent AC problem and once again, the pressure switch has failed. A new pressure switch will be installed on Monday for a total of $174.00. It will be interesting to see how long the repair lasts. I'm going to contact the Volvo dealership about this issue next week. I sure hope this helps other frustrated Volvo owners.

Ann




Symptoms of a Bad or Failing AC Pressure Switch

If the AC is cutting on and off rapidly, unable to cool the cabin, or failing to turn on the compressor, you should replace your AC pressure switch.



The AC pressure switch is a safety switch that is mounted on both the high and low sides of the air conditioning system. It monitors the pressure of the refrigerant on its respective side of the system. There is a high side pressure switch, and low side pressure switch, and they both serve to monitor the system for pressure faults that can damage the compressor.

When the pressure is too low, the compressor risks damage due to running with low oil. When it is too high, the compressor is at risk of overheating and becoming damaged. Depending on which side of the system the sensor is mounted in, when the pressure rises too high or drops too low, the switch will turn off the compressor to prevent damage from occurring. As the pressure switches serve to protect the compressor and rest of the system from damage, they play an important role for the proper function and service life of an AC system, so they should be replaced if they are causing problems. When they begin to fail they will usually display a few symptoms that will alert the driver of a potential problem.

1. AC system cutting on and off rapidly

Repeatedly cycling on and off is part of the normal operation of an AC system. There are periods where the AC is turned off, such as when the proper temperature has been reached, and the pressure is adequate. However, if the system is cycling on and off very frequently or more rapidly than normal, it could be a sign that the cycling switch is not functioning properly.

2. Unable to cool the car

If either of the AC pressure switches fails, then the system will have a difficult time maintaining the pressure required to function properly. If the pressure is not right, then the AC system will not be able to produce the cold air required to adequately cool the cabin. You may notice that the cabin takes longer than usual to reach the correct temperature, or may not even be able to reach the correct temperature at all.

3. Compressor not coming on

As the pressure switches control the on/off function of the AC compressor, a switch failure can prevent the AC compressor from functioning at all. The compressor is what pumps refrigerant through the entire system. If it is not functioning, then the system can not operate, and will be unable to produce cold air.

Because the AC pressure switches play such a vital role in ensuring the proper operation and service life of the AC system, any problems with them should be addressed immediately to ensure the integrity of the system. If you suspect that one of your AC switches is bad or failing, have it diagnosed by a professional technician from YourMechanic. If necessary, they will be able to replace your AC pressure switch so that you can ensure the system remains functioning correctly.
 

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Great information. My S80 occasionally won't start the AC compressor. After some high revs it comes on and is fine. I have AC gauges and the pressures are correct. This explains why it is intermittent.

Thx!
 

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I've been looking around at my S80 problem. Looks like there is only one AC Pressure Switch and a real Volvo one is available.

Can anyone confirm that there is only one? Do we know if there is a schrader valve at this location? For $125 bucks or so I'll change my own.

thx!
 

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My 2011 XC60 R-Design is having issues of blowing warm air for the first five to ten minutes of operation, then will start blowing cold air, then sometimes goes back to blowing warm air. Does this seem like a similar issue?

I have checked the freon level and it is good...The guys at my local dealer want to pressure test the A/C system, remove the old freon and replace it with new freon. Big $$$$.
 

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If there is the correct amount of freon in the system, the best way to diagnose this is with a set of AC gauges. 9/10 the pressures on the high and low side will be close to equal. Start with a switch. Always start with an A/C service 1st.
 

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If there is the correct amount of freon in the system, the best way to diagnose this is with a set of AC gauges. 9/10 the pressures on the high and low side will be close to equal. Start with a switch. Always start with an A/C service 1st.
Thanks! I am going in this Friday to have this issue diagnosed/serviced. Will keep everyone posted.
 

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I've been looking around at my S80 problem. Looks like there is only one AC Pressure Switch and a real Volvo one is available.

Can anyone confirm that there is only one? Do we know if there is a schrader valve at this location? For $125 bucks or so I'll change my own.

thx!
Where did you find the real Volvo switch? Do you have a video or instructions of the switch being replaced? I would also be doing this myself. I will first check to make sure there is ample flow of electricity to the AC Pressure Switch.

Did swapping this AC Pressure Switch solve your AC problem?
 

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Where did you find the real Volvo switch? Do you have a video or instructions of the switch being replaced? I would also be doing this myself. I will first check to make sure there is ample flow of electricity to the AC Pressure Switch.

Did swapping this AC Pressure Switch solve your AC problem?
FCP Euro has a Volvo A/C Pressure Switch - Genuine Volvo 31305844

I have not done mine yet. Could not find a video any where.

I have a set of AC gauges like mentioned above. Made sure the freon amount was correct. It acts much better and is freezing cold. Occasionally it does not fire up right away, which I believe is the pressure switch.

Still looking for the answer as to if these cars have schrader valves. If they do not the freon will need to be evacuated before removing. If they do have a schrader valve the switch can be taken off and put back on with no loss of freon.
 

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Only the CCOT system cars have two switches. 700/900 models, the P80s (850, S70/V70/C70 cloth top), and the P1 models use this type with an orifice and cycle compressor using a low pressure switch. They (well 850 non turbo 93-94 didn't) use the pressure switch for fan speed control. The P2, P3, and Nedcar S40/V40 use expansion valve have only the pressure switch but also use the evaporator temp sensor to cycle compressor if evaporator air temp gets low enough to mean freezing is a risk. For that matter SPA(P5) and CMA (P6) use this setup too. The V8 P2 and 3.2 P2 and all P3 and anything newer uses variable displacement compressors. These have the solenoid that varies crankcase pressure which changes angle of the piston driving swashplate. The swashplate angle varies piston stroke and thus displacement. The evaporator temp probe is read by climate control module and then is network communicated to the engine control module. P3 models have some delay before the ECM changes the compressor solenoid signal to full displacement. The solenoids can stick and will usually do it until compressor temperature warms up due to engine warming the compressor up. The solenoids can be changed but on some the compresor has to be partly or totally removed and always has to have refrigerant removed and recharged after the valve is changed. I suggest new compressors when the valve fails on the ones with removal needed since the risk of compressor failing after all that money is spent is going to make most angry. On the ones where the solenoid is readily accessible I changed the valves unless I see too much greying in the bore indicating impending failure. The high pressure switch is only schrader valve mounted on P80 models to my recollection. The ones where it is screwed into receiver drier and most screwed onto high side line other than P80 are into an open hole. There is risk on the schrader valve ones that the refrigerant escapes suddenly when you unscrew it so be careful with those and unscrew one turn and see if it stops hissing.
The pressure switch is used as a safety shut off for too high pressure (425 psi +/-) or for no refrigerant or too cold ambient temp if pressure is too low (<33 psi) but when it is slow to cool (> 60 seconds after start) then that is usually sticking solenoid for the VD compressor models.
 

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Only the CCOT system cars have two switches. 700/900 models, the P80s (850, S70/V70/C70 cloth top), and the P1 models use this type with an orifice and cycle compressor using a low pressure switch. They (well 850 non turbo 93-94 didn't) use the pressure switch for fan speed control. The P2, P3, and Nedcar S40/V40 use expansion valve have only the pressure switch but also use the evaporator temp sensor to cycle compressor if evaporator air temp gets low enough to mean freezing is a risk. For that matter SPA(P5) and CMA (P6) use this setup too. The V8 P2 and 3.2 P2 and all P3 and anything newer uses variable displacement compressors. These have the solenoid that varies crankcase pressure which changes angle of the piston driving swashplate. The swashplate angle varies piston stroke and thus displacement. The evaporator temp probe is read by climate control module and then is network communicated to the engine control module. P3 models have some delay before the ECM changes the compressor solenoid signal to full displacement. The solenoids can stick and will usually do it until compressor temperature warms up due to engine warming the compressor up. The solenoids can be changed but on some the compresor has to be partly or totally removed and always has to have refrigerant removed and recharged after the valve is changed. I suggest new compressors when the valve fails on the ones with removal needed since the risk of compressor failing after all that money is spent is going to make most angry. On the ones where the solenoid is readily accessible I changed the valves unless I see too much greying in the bore indicating impending failure. The high pressure switch is only schrader valve mounted on P80 models to my recollection. The ones where it is screwed into receiver drier and most screwed onto high side line other than P80 are into an open hole. There is risk on the schrader valve ones that the refrigerant escapes suddenly when you unscrew it so be careful with those and unscrew one turn and see if it stops hissing.
The pressure switch is used as a safety shut off for too high pressure (425 psi +/-) or for no refrigerant or too cold ambient temp if pressure is too low (<33 psi) but when it is slow to cool (> 60 seconds after start) then that is usually sticking solenoid for the VD compressor models.
Excellent information. It works for the most part so I am going to let this one wear for a bit longer before I make a decision. Thank you!
 

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So my issue was, simply, a bad AC Compressor Control Valve. $550 later.

The initial AC inspection did not consist of much. The tech mentioned that the high pressure Schrader valve broke off and spewed freon everywhere...I was the one that had to fish out the broken portion in order to put a replacement valve in. He initially scared me with the possible necessity of replacing a bunch of AC tubing ($950) worth of repairs (because of the broken valve) and still no fix for the AC. In the end, the "assessment/inspection" consisted of him removing the freon from the system (by a machine), refilling the freon, checking for a leak, and the mechanic telling me he wanted to replace the entire compressor (NOT the AC Pressure Control Valve, this was my idea). He did not check the electricity to the wire terminals nor did he even simply checked to see if the high and low pressure sensors that relay information to the AC Pressure Control Valve were working.

Oh, and the local dealer had THREE different part numbers for the valve...I made sure to get the valve that was made in Poland (31436166). NOT: 31365093 (which was the first one they ordered, made in Japan), nor 31305844.
 
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