Why Is My Air Conditioner Not Blowing Cold?
Refrigerant Leakage
By far the most common reason why you may notice your cars air conditioning is not blowing cold is due to a low refrigerant level. Cars lose refrigerant over time, if your car is more than a few years old it almost certainly is low on gas. This does not necessarily mean you have a leak, however.
Yes, that may sound contradictory, but the truth is most vehicles lose gas over time. In the case, there is no refrigerant in the a/c system or there has been a sudden loss of refrigerant then you almost certainly have a leak.
Condenser Blockage
The condenser is mounted at the front of your radiator. The primary purpose of the AC condenser is to cool the high temperature and high-pressure refrigerant back into a vapour before being cycled back through the compressor. This cooling effect happens when the refrigerant that flows through the tubes of the condenser is cooled by air blowing through the condenser. If your condenser is caked with mud or debris or there is a restriction of free airflow, that will affect the cooling performance of your cars air conditioning system. If the condenser fan is not working properly or has stopped working altogether the condenser will also have adequate airflow.
Compressor Failure
We have extensively covered this topic in previous articles, a faulty compressor is the second most common cause for your air conditioner not to be working or blowing cold. You’re A/C system cannot function correctly with a defective or non-working compressor. It is advisable to run your car’s A/C system for at least 5-10 minutes a week even in the cooler weather. AC compressors can leak particularly on older vehicles.
Electrical Issues
A short circuit in the electrical system or broken wires can be another reason why your cars air conditioner compressor is not blowing cold air. However, a visual inspection of the wiring can be undertaken and repairs made where necessary. It can be tricky identifying electrical issues. The first step would be to check that there is adequate power to the compressor. If there is no power to the compressor you may have a blown fuse or bad relay which is usually a cheap and easy fix. However, more complex repair work may be best undertaken by an Auto Electrician or A/C specialist.
Evaporator
This is the only component that is located inside the cabin behind the dashboard. The rest of the components are located under the bonnet in the engine bay. The evaporator looks like a miniature-sized radiator, it also contains many fine fins and tubes. Evaporators can leak and are the one part of your car’s A/C system you cannot see until it has been removed. There are several ways to determine if the likely cause of refrigerant loss is through the evaporator, but this job is best left to experienced technicians to determine. On most occasions, the dashboard must be completed from the vehicle to gain access to the evaporator, so a correct diagnosis before undertaking this work is essential.
Leaking Hoses
Most vehicle A/C hoses are made of rubber, over time this rubber will shrink and harden causing Refrigerant loss. The most common place an air conditioning hose will leak is at the crimp. The crimp connections are called ferrules. When hoses are newly manufactured, they are soft and flexible. This rubber hose will harden dramatically over time. The ferrule will no longer retain a tight seal surrounding the rubber hose and refrigerant can seep through this joint. A/C hoses should always be dry, if your hose looks wet or oily, particularly from where the rubber is crimped your hose is likely leaking. Most hoses can be repaired however this takes specialised tools.