Heater core: What it is, how it works, the symptoms of a leaking heater core and how to fix

Is your car’s heater not working as it should? The heater core, could be the culprit. This essential component keeps your vehicle’s interior warm during cold weather, and when it fails, you need a quick and reliable solution.

Discover how a heater core works, common signs of failure, and why it’s crucial to address issues promptly. For an easy and effective fix for heater core leaks, trust K-Seal. Find a stockist today and get back on the road with confidence.

Where to Buy K-Seal

What is a heater core?

The heater core is also known as the heater core. It works in a similar way to the car radiator but, instead of removing heat to the outside air, it transfers heat to the vehicle interior to help keep you warm.

The heater core

What does a heater core do?

The heater core is a small radiator which uses conductive brass or metal tubing and a fan to transfer heat from hot coolant making its way around the cooling system out into the air of the interior of the vehicle. In this way, it can provide heat to the driver and passengers during cold weather.

Why do heater cores fail?

Heater cores can fail for several reasons:

  • Clogging: The tubing that makes up the heater core can become clogged over time with dirt and other contaminants that can be picked up by the coolant if it is not flushed out and replaced on a regular basis. This will eventually lessen its effectiveness and it may stop working completely if it is not maintained.
  • Heater core leaking from Electrolysis: Electrolysis, a chemical reaction where electrical currents flow through the coolant, can corrode the heater core tubing. This can eventually make the heater core tubing spring a leak. Even a tiny pinhole leak can disrupt the system and worsen over time.

What are the symptoms of a heater core leaking and failure?

It isn’t easy to recognise the symptoms of heater core failure for what they are. You might not know that some of these symptoms signify a problem with the heater core, which is why it’s important to identify and deal with them as quickly as possible. They include:

How much will a heater core repair cost at a garage?

Whilst the cost of a replacement heater core part isn’t particularly high, there is a large amount of labor involved.

The dashboard has to be completely removed to access the area where the heater core is located and, while the actual job of replacing the heater core isn’t particularly complicated for a competent mechanic, the whole task can take several hours. 

It may take longer depending on the type of vehicle being worked on, and this means that the costs of the job may stretch into the thousands, and certainly the hundreds.

Car mechanic passing car keys to the car owner after repairing the heater core.
Car mechanic passing car keys to the car owner after repairing the heater core.

Can K-Seal fix my heater core?

If you’re looking for a heater core leak quick fix, then you’re in luck — K-Seal will fix most leaks in the heater core. 

How to use: When using K-Seal for this type of repair make sure that the heater is switched to maximum so that K-Seal flows through the pipes and reaches the leak, permanently sealing it.

Want to get hold of a bottle to fix your heater core? Use our simple stockist search and get back on the road – fast.

Could other parts of my engine be affected?

Although your heater core could be the source of your engine troubles, it might not be the only component you need to take a look at. Select an engine part in the interactive diagram below to explore your engine and the important components that keep everything ticking over.

Click on the engine components below for details
More Info »

Still not sure what the problem is? Try our 60 second problem solver to quickly identify what the issue is based on your symptoms.

K-Seal Is The Best Way To Repair Engine Heater Core Leaks

Expert Advice

Head Gasket Failure? Cracked Head or Block?
Leaking Radiator?

Expert Advice

Where to buy K-Seal

Have any of these symptoms? K-Seal could save you thousands on a workshop repair. Search for a stockist today!

Find a stockist