If you’re struggling to get through the winter without getting turned into a human popsicle, you may be understandably upset when your car heater stops working effectively. Over the course of this guide, we’re going to take a look at some of the reasons why your car heater is not blowing hot air.
The most common reasons why a car heater may not be blowing hot air include a faulty heater switching system, a clogged cabin air filter, a faulty thermostat valve, or a clogged heater core. Depending on the severity of the issue, you may be able to fix the problem at home or you may need to take your car in for servicing.
Fixing a car heater can either be simple or complex, just like fixing issues like brakes not bleeding or making a grinding noise but a paragraph is hardly enough space to go over all of the potential issues and solutions to your car heater’s problems. We’re going to take a more detailed look at some of the problems that you may run into and how you can get your car heater working again.
Car Heater Not Blowing Air
The first thing to consider is whether or not your car heater’s switching system is functioning properly. If you’re having an issue with this system, it means that your car heater will probably not turn on in the first place, leaving you with either cold air blowing through the vents or no air at all.
Switching System Issues
To see if there’s a problem with the switching system, the first thing that you’ll need to do is determine whether or not any of the fuses have blown in the fuse box. Also, take a look and see if the light indicator for the heating system is turning on. This is usually the little light on the knob or button for the heater.
Also, listen closely when you turn on your car heater. You should hear a small clicking sound when you do it. Another thing to ensure is that you’re not running the AC at the same time as the heater. Some cars have lockouts to prevent you from doing this, but that’s not the case with all vehicles.
Finally, if your car is equipped with a climate control system, you’ll need to take a look at the temperature you have the vehicle set to. If your temperature is too low, then the climate control system won’t end up turning on the heater to make sure that the temperature stays within the range that it’s set to.
Clogged Air Filter
Another potential issue that you may be dealing with is a clogged air filter. This can also happen with more reliable vehicles like Dodge Rams. Air filters are installed on car ACs and heaters to ensure that the air coming in is clean of any particulates. Since the air is usually coming from the engine bay, it’s a good idea to have it filtered before it reaches the passenger compartment.
Over time, the filter for your car heater or AC will end up getting filled with this particulate matter, and it may end up clogging the filter. To ensure that you don’t run into this issue, you’ll want to make sure that you regularly clean the air filter, especially when you bring your car in for maintenance.
You can also clean out the air filter yourself if you’re confident in your ability to maintain your vehicle. Start by finding the air filter for your particular model of car. You can find it in the vehicle manual or you can do a quick search online so that you know where it’s located.
Once you’ve found the filter, take it out of the car and take a look at it. If the air filter is clearly clogged, you may be able to clean it out. However, older air filters should usually be replaced instead of cleaned, so make sure that you get the same model from your local auto shop and slot it in.
Thermostat Valve Issues
Yet another potential issue that you may run into is a malfunctioning thermostat valve. To check the thermostat valve, you’ll want to make sure that your car is parked on a level surface and that the parking brake is engaged. Ensure that your car has had ample time to cool down so that you don’t burn yourself.
Open up the car’s hood and find the radiator. Once again, you can find this with a quick internet search or a search through the car’s manual. Trace the path of the hose that connects to the radiator back to the engine itself. At the end of this hose, you’ll find the thermostat valve.
Be sure that the engine is cold so that you don’t burn yourself and then take out the thermostat valve. You’ll know that you have an issue with your valve if the valve’s spring is loose. When you go to the auto shop to find a replacement thermostat valve, be sure that it has the same temperature rating as the one you took out.
Heater Core Malfunction
The final issue that you may have to deal with is a malfunctioning heater core. This is a heat exchanger that takes the heat from the engine and adds it to the air that’s coming through the ventilation system so that the heater works in the first place. As you may have guessed, replacing this will be a bit more challenging than dealing with the other issues we mentioned.
Over time, rust and salt will begin to clog up the heater core. Like most heat exchangers, it’s made up of a row of pipes, and when these pipes get clogged, the heat can’t be exchanged because the hot water won’t be able to move through the pipes freely enough to bring the heat over.
The problem with a faulty heat exchanger is that it will be difficult to access since you’ll usually have to disassemble a large part of the car’s interior to reach it. In this case, you’re often better off leaving the issue to be sorted out by a professional mechanic.