Side effects of bypassing heater core
Understand the consequences of bypassing your vehicle's heater core.
The heater core keeps the vehicle cabin warm, but what happens when it pulls out or becomes faulty? Unlike some other components of the system that require immediate replacement, it is possible to bypass the heater core if you do not want to replace it immediately.
Bypassing the heater core keeps the cooling system functioning and curbs coolant leaks and further threats to the vehicle. However, you must understand that bypassing the heater core is a temporary repair and does not guarantee that all is well. Even when the system is still working correctly, some potential side effects bypassing the heater core have on your vehicle.
So what are the side effects of bypassing the heater core? If you have considered bypassing your heater core but are wondering what else could go wrong if you do, this article addresses the side effects of bypassing the heater core and other things you should know.
Why would you need a heater core bypass?
You don’t need to bypass the heater core every time the heater malfunctions. It is possible that the heater core is clogged and needs to be flushed, not bypassed entirely. The fault could also be that the blower fan is not working correctly or an electrical issue in the system not making the heating system respond well. If any of this is the case, you should focus on fixing the problem rather than bypassing the heater core.
You should only bypass the heater core for two significant reasons to help the system function effectively. The first is when the heater core is damaged or worn out. A damaged heater core could have holes that leak out the coolant from the system resulting in a collapse of the cooling system and heating system and, consequently, overheating.
The second reason is that a damaged heater core in the system will lower the system’s pressure, affecting the engine’s efficiency. In such cases, you will have to replace the heater core or bypass it to salvage your engine from further damage.
Should you replace or bypass a bad heater core?
The choice to bypass or replace a bad heater core is solely yours. Two reasons allow people to decide whether to bypass or replace the heater core in their vehicles.
The first is the climatic condition of their region. If you live in a cold area, you shouldn’t think of bypassing your heater core. The reason is that the heater core blows hot air into the cabin to keep it warm; bypassing it would mean a lack of heat in the cabin, making you freeze inside your car. For those in hot climatic regions, bypassing the heater core would sound like a great idea and can be. You wouldn’t need more heat anyway.
The second reason is the cost. The heater core bypass is affordable as compared to replacing it. On average, it takes about 12 hours to fix a new heater core, and the cost ranges between $550-$1,000; with labor taking the bulk of it, the heater core sells for $25 to $150. Bypassing the heater core should take about $90 to $100 of labor and is relatively easy.
What are the side effects of bypassing the heater core?
As much as you may want to remedy your engine from further damage by bypassing a faulty heater core, you should also be aware of the side effects of this bypass. If you are wondering what effects bypassing the heater core would have on your vehicle, these are some.
Lack of heat
Bypassing the heater core may not be a big deal until you drive in a cold climate. The most noticeable side effect of the heater core is the lack of heat. Since the heater core generates the heat for the cabin, bypassing it also means bypassing its functions, which means no heat for the cabin. A heater core bypass is not something you should try during cold seasons. If your heater core goes bad during winter, you should consider replacing it to avoid freezing in your car. To ensure that your car’s A/C is blowing hot air, bypassing the heater core is a no-go.
Rust and corrosion
Bypassing the hearer core prevents it from functioning with the other parts of the system and leaves it idle. When it remains inactive and abandoned for some time, the heater core becomes prone to rust and corrosion; rusting or corrosion is unsafe for the system.
Before you think of bypassing the heater core, know that fixing it is always cheaper than swapping to a new one, but if the core gets rusted, it will become difficult to repair and require a total replacement.
Threat to windshield defogger
With no heat from the AC vents, the windshield defogger system could become weak or stop working. When this happens, fogs on the rear glass or windshield would not dissipate in cold conditions and might threaten the vehicle. Driving a car with a malfunctioning windshield defogger might result in an accident.
Can I drive with a bad heater core?
No. Driving a car with a faulty heater core is not a reasonable thing to do, as a bad heater core causes some overheating problems. When the heater core is bad, it can leak out the coolant from the cooling system, causing the cooling system to malfunction and the engine to overheat. And you know better than to drive an overheating car.
A bad heater core can stop heat from entering the cabin, and leaking coolant could harm your health. If you notice signs that your heater core could be faulty, it is advisable not to drive it until you bypass or replace it.
Does bypassing the heater core affect the engine performance?
After bypassing, the cooling system should be able to function appropriately again without any effect on the engine or its performance. The bypass shouldn’t affect the engine or its performance if correctly done but bear in mind that bypassing the vehicle’s heater core is patchwork to allow the engine to run for some time. The coolant could leak if the bypass is haphazard, making the engine overheat.
Our take
Bypassing the heater core is a viable option that can help your engine last some more when you don’t want to deal with the time and cost of replacing the heater core yet. It is easier and less costly than replacing the core, but unfortunately, there are some potential side effects too.
First off, bypassing shouldn’t be an option for you if you live in cold zones, as this would lead to a lack of heat in the cabin, and you may freeze inside. Even if you don’t mind some cold inside the car, bypassing should be a temporary repair option as it compromises the windshield defogger system and threatens you and your vehicle.
When you bypass your heater core, you should consider replacing your heater core as soon as possible to avoid further disastrous occurrences.
Does bypassing the heater core affect the air conditioning?
The heater and the HVAC system are distinct from each other. While the AC uses refrigerant to remove heat from the cabin, the heater uses the engine coolant to blow heat into the cabin. Bypassing the heater core should not affect the air conditioning because the AC has a valve that shuts its flow from going into the core when it is not in use.
Can heater core bypass cause overheat?
The goal of bypassing the heater core is to allow the coolant to flow into the engine and reduce the chances of overheating, but the cooling system works more effectively when the heater core is working too. There is a chance that your car might face some issues, and your engine might overheat.u003cbru003eu003cbru003eIf the car overheats after a bypass, it is because the heater is still faulty or wasn’t successful. There could also be an issue with other engine components or a cooling system’s coolant shortage. If your car overheats after a bypass, you should try replacing the heater core.
Why would you need a heater core bypass?
When there are holes in the heater core, it causes coolant leaking, leading to a shortage of coolant in the system and, subsequently, overheating. Holes in the core also reduce the system’s pressure and cause it to malfunction.u003cbru003eu003cbru003eWhen this happens, the heater core needs to be replaced or bypassed. Replacing the heater core can be time-consuming and expensive compared to bypassing it. If you can’t afford it, bypassing the heater core works fine.
