Why is my car heater not working? – The AA

Why is my car heater not working? – The AA

Dream Cheeky will help you know How To Fix The Heat In A Car 2022: Full Guide

Video How To Fix The Heat In A Car

During the colder months, your car heater keeps you warm on drives and helps defrost the car on icy mornings. Which means it’s not ideal to suddenly find your heater not working.

Below, we explain how a car heater works, why it may not be working and what you can do about it.

Read more useful advice on driving during winter.

Car heater and AC thermostat

How does a car heater work?

Most car heaters use coolant to warm up the interior of the vehicle. Here’s how it works:

  1. The vehicle engine heats the coolant to a very high temperature.
  2. The coolant is pushed through the heater core (which acts like a mini-radiator).
  3. Air is pushed through the heater core, resulting in hot air blowing into the car.

Often when you first turn the heating on, you’ll notice the air feels cold for a few minutes – this is because the engine needs a little time to warm up and heat the coolant.

Why is my car heater not working at all?

If the heating system isn’t working at all (no hot or cold air is being blown into the car), this is likely due to a faulty blower motor or an issue stopping power from reaching the blower motor.

We provide 24/7 roadside assistance.

Why is my car heater blowing out cold air when the engine is on?

If you’re only getting cool air when your heating is on, it could indicate a problem.

First things first, make sure you’ve set the system to hot. And let the engine run for a few minutes to give it time to heat up the coolant.

If you’re still getting cool air, then there are a few reasons this might be happening. The most common reasons are:

  • Your engine coolant is low.
  • There’s a fault with the thermostat.

How to fix a car heater

The first thing to do if you’re having issues with your car heater is to check your engine coolant. Make sure to do this when your engine has cooled down to avoid being burned.

If your coolant level is too low, there won’t be enough hot liquid in the heater core, resulting in cold air. You should top up the coolant to the appropriate level and then check to see if the heating is working again.

Low engine coolant can be a sign of a leak or other issue in the system so you should also get your vehicle checked by a professional to make sure there are no further problems.

If there is enough engine coolant but the heating still isn’t working, you’ll need to take your car to a garage so an experienced mechanic can diagnose and fix the issue.

How much does it cost to fix a car heater?

The costs involved in fixing a car heater can depend on the problem and what needs replaced or mended.

A full replacement of your heater core can be expensive due to the labour involved, costing upwards of £1,000 for parts and labour.

Find out what’s causing your car’s heating problems with Smart Care.

How does the heater in an electric car work?

Unlike internal combustion engine vehicles, the motor for electric vehicles doesn’t create heat as a by-product of running. This means EVs need another way to heat up the car.

Most modern EVs use a heat pump, which takes thermal energy from outside air and compresses it before releasing the heat inside.

An EV’s heating system does rely on power from the traction battery, which used to result in the range of electric cars being much shorter during winter. But with modern EVs, the heat pumps are very efficient so this is no longer an issue.

Plus, one of the benefits of driving an EV during winter is preconditioning – this means you can pre-heat or pre-cool your car before you start your journey.

This handy feature means you can warm up and defrost your car in the morning while it’s still charging, so it’s ready for you when you want to drive it and there’s no impact on the battery charge.

Read our guide to maintenance and repair for electric cars.