Having a leaking heater core can be one of the most frustrating leaks you can have in your vehicle. Almost any leak in your car is an external leak, meaning the leaking fluid will just leak out onto the ground. Sure, that isn’t the best for the environment and it can make a mess in your driveway or the parking lot at work, but at the end of the day as long as you keep your fluids topped off, you can keep driving your vehicle relatively comfortably.
What Does A Heater Core Do?
The purpose of a heater core is to bring warm coolant into the cabin of your vehicle so the ventilation air can be warmed up allowing your car’s defroster and heater to work properly. Think of it as a small radiator.
What are the symptoms of a leaking core?
A leaking heater core usually will cause a much more annoying leak. On most new vehicles, the heater core is inside the cabin of the vehicle. Even if you have an older vehicle with the heater core outside the cabin, leaking fluid can still find its way into the cabin through the ventilation ducts.
Having coolant leaking into the cabin of your vehicle can cause all sorts of problems. First, when your car isn’t warmed up yet, the coolant will make a mess on your floorboards and possible start the process of corrosion. As the coolant leaks onto your floor it will soak into your carpet and the padding. As this moisture stays trapped in your carpet it can start to corrode the floor pan in your car. Since this is all happening under the carpet, it can quickly get out of control without you ever knowing. In the worst case, this corrosion can compromise the integrity of the floor of your vehicle making it unsafe.
Another problem with coolant leaking into the cabin of your vehicle is that once it is warmed up, that coolant will be almost 200 degrees! This hot coolant will quickly turn to steam in your car and will definitely cause an unpleasant odor. The steam can also quickly spread through your ventilation system making it very difficult to remove the odor. Depending how big the leak is, the steam can cause fogging problems on your windows and leave you with no way to clear the condensation since it is your ventilation system that is spreading the problem. Lastly, antifreeze is a poisonous substance so breathing in its vapors can even be harmful to you and your passengers.
If you have a leaking heater core, then you may have experienced some of these symptoms and have realized how frustrating it can be. It isn’t unusual for heat cores to develop leaks because they are often made from relatively thin metal to help aid in the heat transfer from the hot coolant inside to the air being blown over it by your vehicle’s HVAC system. This thin metal can develop cracks over time and the joints in your heater core can start to come loose due to vibrations in your vehicle and bumps in the road.
Can I replace or repair a leaking core?
Replacing a leaking heater core can be an extremely annoying project due to its location in your vehicle. The heater core needs to be right next to the fan that pushes the air through your ventilation system. That fan needs to be near the firewall of your car so it can have the ability to both pull air in from outside the vehicle, or recirculate the air in the cabin depending on the settings of the system. If you have air condition in your car, then the AC evaporator will be right next to the heater core which is also a delicate piece of equipment that is difficult to move.
Fixing a leaking heater core will always be much easier than replacing one. Since it is only a small leak in the heater core, we recommend simply sealing that leak and leaving your heater core in place. You can do this by simply by adding BlueDevil Pour-N-Go to your vehicle’s radiator when your vehicle is cold. When BlueDevil Pour-N-Go reaches the leak point, the temperature differential will cause a chemical weld to form sealing your leak without affecting any other part of your cooling system.