Need an Air conditioning heating inspection?
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Air conditioning heating inspection
What is the air conditioning heater?
In Australia, a car’s heater is often used in the winter months. It is, therefore, a good idea to test the heater every few months to make sure it’s ready to go when the temperature does drop. If you find the heater is out of action or not pumping out as much heat as expected, then an inspection of the unit will be required to determine what has failed and what might need to be repaired or replaced.
The heater is part of the heating, ventilation and air conditioning system (HVAC). When this system is not working effectively it can cause uncomfortable driving conditions, especially if the heater decides to fail in the middle of winter.
Since the heater is also used to help remove fog from inside the windows, it isn’t just the comfort factor to consider - there are obvious risks to driving without a clear view.
WINDOWS FOGGING UP? How to stop the fog
How does the heater work?
The heater element of the HVAC system involves a number of components, including hoses, valves, a heater core, blower motor and fans, and a control switch.
While it may sound paradoxical, it is actually engine coolant that is used as the heat source. It is first used to cool the engine, a process that will see it absorb at least some of the heat generated during an engine’s operation. This action heats up the coolant considerably.
This hot coolant then flows through the heater core (behind the dash) which works like a mini radiator. The hot coolant flows through the core and a fan blows over fins within the core which transfers the heat to the cabin.
You would have noticed that the heater takes time to warm up. This is because the engine needs to warm up first. When the engine is hot enough, a thermostat opens to allow coolant to flow and the process begins. This process doesn’t usually take too long but when you’re cold it can feel like an eternity!
Of course the heater wouldn't work at all without a control panel, and electrical switches, wiring and fuses are required for the system to operate. Because there are so many components that combine to make a heater work, diagnosing any problems requires a systematic approach.
Common reasons for the heater to not work
- Faulty heater core
- Air in heater system
- Faulty thermostat
- Blown fuse
- Failed blower motor
- Wiring issue
- Low coolant levels
How is an A/C heating inspection performed?
A qualified air conditioning (A/C) technician is required to inspect and diagnose any HVAC system concerns.
The A/C tech will look at the most obvious areas first and then systematically test all heater component functionality. They will check the following:
- Check coolant levels and look for leaks or contamination
- Ensure the blower motor is operating properly
- Check for blown fuses
- Check the electrical system
- Test heater control switch
- Check heater core, valve and hoses for faults, blockages or leaks
- Inspect if there is air in the system
- Check thermostat operation