4 Common Causes of a Clogged Heater Core
There are numerous potential causes of a clogged heater core. While each of these causes differs in origin, all lead to the same troubling condition, which must be remedied in order to restore heater core operation back to peak efficiency. The following are several of the most common causes of a heater core leak.
1) Rust/Scale Build-Up
Corrosion of any type is extremely detrimental to a vehicle’s cooling system as a whole. However, heat exchangers found within this system are especially prone to problems resulting from rust and scale build-up.
This includes the heater core, which tends to clog quite easily. Rust and scale build up of this type often result from the prolonged use of water within a vehicle’s cooling system.
2) Mixing of Oil/Coolant
When oil and coolant mix, sludge is created as a byproduct. This sludge quickly spreads throughout a vehicle’s cooling system, including the heater core.
Due to the density of this sludge, clogging often occurs, ultimately slowing or eliminating the flow of coolant throughout the heater core. Gasket failure is by far the most common cause of oil/coolant mixing.
3) Use of a Stop Leak Product
Many vehicle owners choose to use various stop leak products to eliminate cooling system leaks of one type or another. However, these products tend to cause clogging within a vehicle’s heater core.
This is especially true when more than the recommended amount of such products are used. Stop leak products can also clog a vehicle’s radiator in a very similar manner.
4) Restricted Hoses
Heater hoses are responsible for transferring coolant from the engine to the heater core. These hoses play an important role in maintaining adequate coolant flow, which allows your car’s heating system to work as it should. Over time, wear and tear, debris, and other factors can cause these hoses to become restricted or even collapsed.
When the hoses become restricted, the circulation of coolant through the heater core may be reduced or even stopped and can lead to the issues mentioned above.
How to Bypass the Heater Core
At times, bypassing the heater core is a temporary solution when you experience a clogged or leaking heater core. Here’s how to do that:
1. Locate the Heater Core Hoses
Find the two hoses that connect to the heater core at the firewall in the engine compartment. These hoses are typically the same diameter and run from the engine to the passenger compartment.
2. Disconnect the Hoses
Carefully disconnect the hoses from the heater core. Be cautious of any coolant spills, as the coolant can be hot and cause burns.
3. Connect the Hoses Together
Using a suitable connector, join the two hoses together. Make sure the connection is secure and doesn’t have any leaks.
4. Secure the Hoses
Use hose clamps to fasten the hoses securely to the connector. Ensure the connection is tight and leak-free.
5. Test the Bypass
Start your engine and allow it to reach operating temperature. Check for leaks around the connection and ensure that coolant is circulating properly.
Keep in mind that bypassing the heater core is a temporary fix and should not be considered a long-term solution. While it may prevent further damage to your engine due to clogged or leaking heater cores, it also disables the heating function in your vehicle.