Symptoms of a Bad or Failing Refrigerant Pressure Switch (Sensor)

The refrigerant pressure switch monitors the pressure in the air conditioning system to ensure it is operating properly. If the pressure gets too low, the switch turns off the air conditioning system. This saves the compressor from running without lubrication and sends a signal that there is a error in the AC system. There are a few symptoms you should look for if you suspect a bad or failing refrigerant pressure switch:

1. Air conditioning works intermittently

When you turn the air conditioning on, does it seem to cool the vehicle down then stop working? Or does it not work all of the time, just at random times? This means the switch may not be working correctly or have an intermittent failure. As soon as this happens, contact a professional mechanic to have your refrigerant pressure switch replaced so you can be comfortable in your vehicle.

2. Air conditioning not working properly

The air conditioning in your vehicle may not seem to get cool enough, causing you to be uncomfortable on a hot day. This can be caused by many factors, and one is a failing refrigerant pressure switch sensor. In hot summer months this can be a safety concern if the outside temperature gets too hot. A mechanic can properly diagnose the issue, whether it is the switch or a low charge in the refrigerant.

3. Noise coming from the AC system

If a high pitched sound comes from the air conditioning system when it is on, this is a sign the pressure switch may be going bad. The switch could be rattling against different parts in the engine compartment, so it is important to have this looked at before other parts are damaged.

4. Blowing warm air

If no cool air comes out at all, it could be a switch problem or another issue within the air conditioning system such as low refrigerant. A mechanic will check the pressure in the system to ensure it has the correct reading. If it is too high or too low, the sensor is most likely failing. In addition, they can read any codes the computer puts out to positively diagnose the problem.

If your air conditioner is not working properly, noises are coming from the system, or it is blowing warm air, contact a professional mechanic. The refrigerant pressure sensor switch is an important part of keeping you comfortable on hot summer days so it should be repaired as soon as possible.

YourMechanic makes getting repairs to your refrigerant pressure sensor easy by coming to your home or office to diagnose or fix issues. You can book a service online 24/7. YourMechanic’s qualified technicians are also available for any questions that may arise.


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Ben

41 years of experience
1410 reviews
Ben
41 years of experience
Volkswagen Beetle L5-2.5L - Heating AC - Houston, Texas
i am well satisfied with Mr Smith working on my car(s). He replaced the Jaguar fuel pump like an expert, and then he diagnosed the VW bug ac compressor and fixed it on the spot. I would recommend him to anyone with a car issue
Nissan Altima - Heating AC - Houston, Texas
Incredibly nice and took the time to show me the problem, including comparison pictures between my unit and what a new unit should look like.

Peter

43 years of experience
1321 reviews
Peter
43 years of experience
Saab 9-3 L4-2.0L Turbo - Heating AC - Phoenix, Arizona
He knows what he's doing. Very polite and explained everything. I would no doubt use him again. I highly recommend him.
Mazda Miata - Heating AC - Peoria, Arizona
We are so thrilled to have found Peter as our new mechanic. He is very thorough and knowledgeable. He is also friendly, professional, and extremely honest. He explained to us exactly what services were needed on our vehicle to repair the air conditioner and provided us with an written estimate of the cost. He literally saved us thousands of dollars in repair costs. A local major competitor quoted us a repair cost of a minimum of $1,400 and said that the cost would go up to $2,400 if they discovered an additional part was required. Peter charged us only $202, plus performed the work at our home. The air conditioner in our 2004 Mazda Miata has honestly never worked so great--it always blew out warm air. We just assumed it was how that particular car was manufactured. We would highly recommend Peter to anyone who is in need of an experienced and honest mechanic.

Pedro

31 years of experience
78 reviews
Pedro
31 years of experience
Chrysler PT Cruiser L4-2.4L - Heating AC - Portage, Indiana
Pedro was wonderful! He was early first and foremost. He was very professional and he explained things to me. He worked quickly and was very thorough. Very happy with his service.

Manuel

32 years of experience
580 reviews
Manuel
32 years of experience
Ford Taurus V6-3.0L - Heating AC - Long Beach, California
Good guy. Knows his stuff. Knowledgeable and straightforward with diagnostics and repair costs. I’d love to work with him again! Thank you Manuel!

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