What is an AC low-pressure hose?
Your car’s AC works using a system of high- and low-pressure hoses that are connected to the evaporator, AC condenser, dryer, and AC compressor. The low-pressure hose is one of the vital hoses that carries refrigerant throughout the system. It’s also called a suction side hose.
Here’s how refrigerant moves through the AC system (starting in no particular order). The system draws in hot air, and the evaporator coil absorbs the heat. The liquid refrigerant in the coil turns into a gas and heads to the compressor. To get there, it travels through the low pressure hose.
The compressor squeezes the refrigerant gas to raise the refrigerant’s pressure. Then, it moves to the condenser, where it comes into contact with outside air. The outside air absorbs the heat, which lowers the refrigerant temperature and makes it shift back into a liquid.
The cold refrigerant liquid travels back through the expansion valve and into the evaporator, where the cycle begins again.
If the AC low-pressure hose begins to malfunction, your entire AC system may be in trouble. If left untreated, your air conditioning system could suffer substantial damages.
How do I know if my AC low-pressure hose is bad?
You’ll probably realize pretty quickly that something is wrong with your car’s air conditioning. Here are signs that the AC low-pressure hose is causing the problems:
The air conditioning isn’t as cold as it should be: If you’re still getting some cool air, just not as much as you’d like, the low-pressure hose might be leaking.
There are crimps or kinks in the hose: Inspect the low-pressure hose for signs of damage. Bends in the hose prevent refrigerant from flowing into the compressor.
The AC doesn’t work at all: The low side moves refrigerant to the compressor, so if the low-pressure hose is bad, the system can’t make cold air.
Refrigerant leaks on the hose: While it’s easier to spot leaks from the high-pressure hose, low-pressure hose leaks appear as a greasy film. Look near the fittings to identify a leaking low-pressure hose.
How often should an AC low-pressure hose be replaced?
AC low-pressure hoses typically last eight to ten years before they need to be replaced. The older the hose is, the more likely it is to leak.
Keep in mind: AC pressure hoses aren’t inspected as part of regular maintenance. If you suspect a problem with your air conditioning system, get the hoses inspected.
Can I replace the AC low-pressure hose myself?
Replacang the hose is a bit more complex than just swapping out parts. Doing the work requires releasing the refrigerant from your car’s AC, and there are EPA regulations about how to do this safely, so it’s not a good DIY project. It’s best to leave the hose replacement to a mechanic who specializes in AC repair.