In today’s episode, John discusses your a/c system. What to look out for, when to get it serviced professionally, things you can do maintenance wise to prevent system failures and much more.

We will discuss the movement from R-134a refrigerant to the newest type called R-1234yf.

Basic theory and operation of the a/c system, the components involved and the items that breakdown, why they breakdown and how that can be avoided.

GOT SWEAT!?

It gets hot and sticky here in New England in the summer! Soon, you’ll be slipping behind the wheel of your car, starting the ignition and powering on the air conditioner. But what do you do if the car air conditioner is blowing hot air or, worse yet, not functioning at all? Here are five tips to help you beat the sweat and some inspiration to fix your air conditioning:

1. EXAMINE THE CABIN AIR FILTER

Your car’s cabin has an air filter, which expedites the flow of air from the air conditioning system under the hood and into your vehicle’s interior. That cabin filter is located either inside your glove box, under the dashboard or under the hood. Wherever it may be, locate it and pull it out. You will know that it is clogged if it is blackened and filled with debris. Replacing it may be all it takes to resolve your car air conditioner problem.

2. RAISE THE HOOD AND CHECK THE CONDENSER

Under the hood, immediately in front of the radiator, sits another part prone to clogging: the condenser. Fortunately, you don’t have to remove the condenser to clean it and free up air flow. Instead, you can used compressed air or even a leaf blower to clean the louvers or if you don’t have those tools available, simply put a garden hose on a medium to high setting and direct the water flow through the grille’s louvers. The lower portion of the grille is an especially important target, as that is where contaminants like road salt will collect.

3. CHECK THE COOLING FAN

What do you do if there is warm air coming out of the vents? Today’s cars are usually equipped with under-the-hood electric cooling fans so when the air conditioner is on, the cooling fan is running, sometimes it turns on a second auxiliary fan in order to handle the extra load of the a/c. If it isn’t working, then either the relay, temperature sensor, control module or fan motor has malfunctioned. In most cases, the relay is to blame for shutting down your air conditioner. Visible signs of corrosion or burnt wiring are a sure indicator that the relay should be replaced. Other items to watch for is the temperature of your engine. Monitor your temperature guage and if it starts to get hotter than normal then you may have a cooling fan problem.

4. EXAMINE THE COMPRESSOR

Another critical component in the car air conditioner system is the compressor. The compressor is tasked with handling low-temperature refrigerant gas and compressing it into a high-pressure, high-temperature gas. When the compressor is working, it sends refrigerant to the condenser. The compressor should be turning if the serpentine belt is turning; if the belt is not turning, it may need to be replaced. If it is turning, then the clutch wire or compressor piston(s) may have broken. Look for signs of fluid leakage at the a/c fittings and hoses. If they are damp then chances are you have a leak and the special lubricating oil for the compressor has leaked out and could cause major damage to your a/c compressor. If the oil has leaked out then it is guaranteed that the refrigerant has leaked out as well.

Other possible problems could be a bad thermostat, bad clutch oil or low refrigerant levels, which can cause the compressor to shut down. Unless you have the tools and the expertise required to address these issues, your compressor problems should likely be left to the professionals at Auto Care Plus.

5. NO AIR COMING FROM THE VENTS?

So, the compressor is running and the air feels cool at the vents but it just isn’t coming out of the vents? Well this could be a problem with your blower motor system. This motor sits behind the cabin air filter and blows air across the evaporator coil and into the cabin to cool you down. The blower motor can blow a fuse, it can get clogged up with rodents, rodents build nests inside the housing of the motor. There is wiring and resistors that change the speeds of the blower motor that often fail. Some can even cause a fire. If you smell burning wires then turn off the a/c and have a professional examine your a/c system.

TROUBLESHOOTING CONSIDERATIONS

Although some air conditioner problems can be resolved using common hand tools, more complex problems may require air conditioning testing, scanning and specialty tools, something not every weekend mechanic owns. When in doubt, take your car to a mechanic — a wrong move could do further damage to the air conditioning system.

Watch on YouTube: https://youtu.be/73YOkgn7_Qk