Cars can be complicated, and it’s easy to be confused about services and terms you hear when visiting an auto repair shop.
Sometimes, drivers may mix up fluids found in a vehicle.
Coolant and refrigerant are a couple of examples. These two fluids are used in different systems.
An automotive professional may mention “coolant” when talking about a car’s cooling system. This fluid helps prevent the engine from overheating.
Meanwhile, refrigerant is associated with the air conditioning system and keeps you feeling cool during those hot summer days.
How the cooling system and a/c system work
The cooling and a/c systems both operate in a circle. However, the parts and process differ.
Cooling systems feature a thermostat that acts like a door and remains closed until the engine block reaches a certain temperature. Then, it slowly opens. The water pump pushes coolant through the radiator. This fluid continues to travel into the heater core and back to the engine block.
As the thermostat opens up, more coolant is able to get into the radiator and keep the engine block at an even temperature.
On the a/c system, you have a compressor that creates pressure. Pressurized lines go into the evaporator, which has larger tubes.
When the refrigerant goes from a tight, high compression into a loose area, it gets very cold.
Like the thermostat, the expansion valve opens and closes based on temperature.
After the refrigerant makes its way through the evaporator, it runs through the condenser, which sits next by the radiator. The air conditioning condenser turns the gas into a liquid. Then, the refrigerant goes back to the compressor.
Looking for coolant and refrigerant leaks
Leaks can occasionally occur in the air conditioning and cooling systems. When they do, we start our investigation with a visual inspection.
If a/c leaks are present and can’t be located, our technicians receive help from a machine and ultraviolet dye. The a/c machine enables them to confirm there is a leak through a vacuuming process. We inject dye and oil before recharging the a/c system.
The customer will then drive their car for a certain amount of time and return to the shop so we can find the dye. It’s a good idea to bring it back after a week, even if the air conditioning system is still working. However, it could take months to spot the leak.
There is no tracer dye yet for 1234yf systems. In these cases, we inject the system with nitrogen and use a sniffer that smells gas.
We can follow a couple of paths to track down coolant leaks. After looking the vehicle over, we pressurize the system using a coolant pressure tester. Two or three times of what the system’s pressure would be is applied, prompting any external leaks to drip.
In cases where a system doesn’t have any external leaks but is experiencing coolant loss, we’ll look for coolant transferring into other systems. Different tests, such as a block test or hydrocarbon test, may be performed.
Kinds of coolant and refrigerant
There are different types of coolant and refrigerant.
Engine metal and coolant requirements differ between Asian vehicles and those made in the United States, for example. European cars also have a specific kind of coolant.
R-12 is the refrigerant needed on cars that were made before 1995 and 1996. After that, R-134a started to be used. R-1234yf can be found on more recent vehicles. More information about AC repair and maintenance can be found in this article we wrote.
Knowing the coolant and refrigerant your car takes could prevent damage and allow these systems to run as designed.
HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located near Lake Ridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.