AC system

ANSWER : Here is the kicker. The old air conditioning systems were huge and they wasted a lot of energy. But with that said, they blew as cool as can be and lasted a long time.

For example, you can take an old Chevy AC compressor – those things were gigantic and some of them weighed 50 pounds – but they blew freezing cold. That said, they used a lot of energy to work and those things held like three pounds of refrigerant. Modern ones don’t even hold a pound of refrigerant and they are all computer controlled. So when they break, they can cost a fortune because not only do they have computers that turn the air conditioning clutch on and off, some of them have the air conditioning clutches that work all the time.

Inside, the compressor have these variable swash buckle plates that are controlled by a computer and can give 0-100% power. And guess what, that stuff is all computer controlled. And when it all breaks, it can cost thousands when they finally break down. So I tend to agree with you that old one’s work better, but the newer ones are much more efficient and they use much less fuel. That’s why they are using them. They get bonus points for better gas mileage from the federal government.

ANSWER : Hi Allen. By far the best way to have your AC system correctly diagnosed is by having an AC inspection completed first. By having one of our professional mobile mechanics come to your location to diagnose the issue correctly, it significantly minimizes the mistakes in completing the wrong service. In your case, the issue could be as simple as needing to have the AC system recharged, or there is an existing leak that needs to be repaired before refilling the refrigerant. Best economic bet is to have the AC inspection completed first.

ANSWER : Hello, thank you for writing in. Although the pulley is still spinning, the compressor has likely failed. If it is not properly regulating pressure in the system, one of the first signs is a warm air conditioner. Considering yours is not cooling off, the pressures are not correct. If you believe the compressor is working correctly, you may want to check for a clogged line before replacing it. Keep in mind, a blocked line has likely put extra strain on the compressor, and may cause premature failure. For more help with testing or replacing the compressor, contact our service department to schedule an appointment.

ANSWER : Hi There,
No, generally the AC clutch spins with the AC compressor. As you may know the AC Clutch is the pulley that spins with the Belt. There are two ports on the rear of the Compressor. One is a Suction Port and the other is the Discharge Port. The Suction port is going to be your larger port and the Discharge port is going to be the smaller port. Refrigerant is sucked into the Suction port, compressed and then it exits out the Discharge Port, then entering the A/C Condenser. Your vehicle’s AC Clutch consists of the Hub, the Pulley, and the coil. The front part of the A/C Clutch is the Hub. Next is the pulley, which is where the belt rides. Finally, under the pulley is the coil, also called a field coil. The Coil is a copper would wire, that functions like a magnetic coil. If the AC Compressor is powered up, electricity engages the coil, and when this happens, it also engages the pulley. The large magnet forces the hub to pull against the pulley. Since the Shaft of the AC Compressor is mated with the A/C Hub, once engaged, it begins to pump refrigerant in the system. Turning whenever the engine is cranked, the A/C Compressor Clutch Pulley will spin even if the AC Compressor is off. If the A/C System is turned on, power is sent to your A/C Compressor Clutch and it will then engage. However, if the pressure in the system (or the refrigerant level) is either too low or high, switches will kill power to the Compressor to keep from damaging it. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle.

ANSWER : Hi there. In both cases, when an AC system is not working and a warning light is coming on the dashboard, typically a professional mechanic will complete the same initial inspection, which is to download the stored error codes that triggered the warning light initially. This tends to give them an idea as to what is causing the problems. This could be something as simple as an electrical relay that is faulty or loose or an indication of a computer related "glitch". Either way, the best way to move forward is to have a professional mobile mechanic complete a check engine light inspection.

ANSWER : The compressor clutch relay on these vehicles are a known cause of sticking on the compressor clutch and overheating the A/C compressor clutch coil. Replace the A/C relay to see if it cures the clutch going bad the next time you do a compressor clutch replacement, or replace it now if you have just replaced the clutch.

ANSWER : If you have detected a refrigerant and oil mist in the cabin, then an evaporator "area" leak is likely. However, any time there is one leak, the entire system should be pressurized (whether pre or post repair) and tested for leaks in order to ensure trouble free operation. To request diagnosis and repair of your system, please use YourMechanic’s a/c diagnostic service page and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : If the low side said 40 and the compressor was running, then the high side should be above 175 or more. I think your gauge is not working correctly. Try an check the pressures with the engine off and cool them. The pressure should be about 10 to 15 above your ambient temperature if the system is full. This means it is 90 degrees outside, then you will read around 100 to 115 psi on the gauge with the engine off. When you start the truck, the low pressure should go down as the inside cools down. It should cycle around 24 psi. If you want to have a mechanic take a look at this in person, a certified technician from YourMechanic can come to your home or office to diagnose your AC system.