Why Heater Only Works When Accelerating? 4 Surprising Reasons!

Do you know why heater only works when accelerating? If not yet, then don’t worry; you come to the right place because we’re here to help you out. There seem to be various reasons why a vehicle heater may malfunction.

The heater in your automobile will not operate if the coolant level is low, the center is not running, or the unit lacks air. The coolant itself might be a problem. 

why heater only works when accelerating

When rusted particles or other contaminants are in the coolant, it may prevent the heating center from distributing warm air to the interior. However, we recommend that you remain unconcerned. Because in this post, we’ll show you some required methods that can significantly assist you in resolving your heating problem. Now we’ll talk about how to find these issues and solve them. Let us discuss more on this below. Keep reading!


Why Heater Only Work When Accelerating?

It’s a common problem that, sometimes, your car works only when you’re driving. We know that you’re curious to know why heater only works when accelerating. Below, we have discussed some basic reasons for this issue and fixed them.


#1. Heater control valve

This is perhaps the fault of the heating control valve. Only a portion of the door may open. This only permits warmer water to flow partially whenever the wattage and RPM load are more than when you drive, or not enough otherwise. The air mixing doors are not listed as an additional option in the heater control system. The cold and warm air “mix” is tested until it is expelled from the air, resulting in so little warm air from the furnace ducts. 

Squeeze the hose on the heating control valve’s outlet end and drive the engine at elevated velocities. If the blower continues to spew hot air, you’ve found the issue. The valve also causes the warning if the air conditioner operates hotter with the hose clamps off. If you’ve determined that a problem with the heating valve is causing the heating system to fail, the valve must be instantly repaired. The sort of valve you have had in the motor determines how you fix the heating valve. If you’ve got a manual valve, the mechanic will fix it by eliminating the faulty pieces. 


#2. Low-level of coolant

This problem has a straightforward solution. Just top up the coolant to a recommended level whenever the engine hasn’t been running for a while or is cool. Also, use antifreeze and water to make a 50-50 mixture, then replenish the coolant to the needed quantity. Remember to check your coolant level every week for the following week to ensure that it’s not a leakage causing your low coolant level. Make sure there’s enough coolant in the system once again. 

The heating pad can be used as the furnace, and the regeneration bottle must be checked. We believe air may be present in your “closed” cooling system. In or out of the car, this might happen. Many gaskets were leaking in any of these vehicles. Examine your gasoline’s condition. Instead of being smooth, it must appear like oil. If the coolant light illuminates while you’re driving, the best course of action is to pull over. Drive your car over to the side of the highway and turn off the engine to prevent the coolant from harming or scorching your engine.


#3. Defective water pump

This may also be possible that the car water pump is not pumping enough coolant, due to which a low coolant level enters the radiator.  However, when the engine runs faster, it will finally pump enough coolant to produce hot air from the cooler surroundings. We recommend monitoring the water pumps. It’s not hard to replace the water pump; the first step in working on the cooling system is determining whether it’s necessary to cleanse it. 

If your coolant is unclean or you’re concerned about scaling, flushing your systems before eliminating any parts is a good idea to guarantee that the previous coolant or rust doesn’t impact the new parts. Replace the water pump with a new, unfilled cooling system. By acquiring a car repair handbook, you will learn the proper procedure for changing your water pump, as well as the exact torque values for installing your recirculation pump. Find out why does my car heater not work


#4. Clogged heater control

After using the control buttons for a long time, they always seem rubbery and stop functioning. If the coolant levels are adequate and the heater’s heart does not appear to be in difficulty, you will need to replace the heater control valve or any control buttons. The heater valve is located beneath your bonnet and is also the key that activates and deactivates the gas. If this component fails, cooler air will become trapped in the cabin of your vehicle.


It’s A Wrap!

After reading this article, we hope you all will know why the heater only works when accelerating. Above, we have discussed four common reasons for this issue; by fixing them, you can get rid of this problem, and your heater doesn’t freeze; it works even when you’re not driving. Thank you, friends, for being with us at the end!

Read related articles; know why is my car heater not working and why is my car heater blowing cold air.

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