A car heater that is no longer functioning can turn a pleasant morning commute into a chilly ordeal to be dreaded every time you wake up.
And let’s face it – resorting to your sleeve to defog a windscreen is far from ideal and potentially even dangerous to you and others on the road.
Fixing a faulty car heater usually requires a mechanic and could be prohibitively expensive for most people without an emergency savings fund. Deciding on the best alternative for you will depend on your particular needs and your budget.
12-volt electric car heaters are commonly used alternatives but don’t produce much heat and are potentially unsafe. Portable propane heaters are another option and don’t require electricity to work. There are also units that use your car’s hot coolant as a heat source, but these usually require a mechanic to install.
Not having heat in your car when you need it can be a real nuisance to say the least. Wouldn’t it be great if there were car heater alternatives to keep you warm on those icy mornings?
Here are the best car heater alternatives to keep you warm and safe:
1. 12-Volt Car Fan Heaters – DO NOT BUY
12-volt fan heaters are a seemingly thrifty and practical solution when you cannot afford to repair your broken car heater immediately.
They conveniently plug directly into the cigarette lighter and claim to be a solution to your heat problems – or at least be able to defrost your windows for only $20-$30. But when something seems too good to be true, it usually is.
While I'd love to recommend a good 12 volt car heat that could at least defrost your windows so you can drive safely unfortunately I just can't find any that are actually good quality and worth recommending.
The truth is that most 12-volt car heaters on the market are not only poorly designed and cheaply built but are also a dangerous fire hazard that you don’t want sitting on your dash.
At best they'll break almost immediately causing no damage to your car. At worst they'll break your fuses, completely drain your battery or actually be a fire hazard.
Most of these 12 volt heaters consume 150W of power but can also be found in a range of wattages between 80W and 200W. That’s a lot of wattage for something with such a cheap build quality; it’s not surprising that most will only work a few times (if at all) before malfunctioning.
The only heater I found which had semi-decent reviews was the RoadPro 12-Volt Direct Hook Up Heater at Amazon. With this heater you need to directly connect it to your car battery and run the wiring through the firewall. But if you're willing to put in a little bit of effort then it can do a decent job for around $50.
It also comes with 2 x 20 amp fuses which means the chances of it breaking the fuses in your car are low. This is a decent product and worth a try compared to the ones you plug into your cigarette lighter.
You can see a video review for this product below.
While the above heater seems ok you should almost certainly avoid the 12 Volt heaters that plug into your cigarette lighter.
Looking at the reviews – the wiring in these products seems to be shoddily done to say the least. Some don’t even have a fuse installed which means that your vehicle’s electrics are in peril when the heater inevitably fails.
Check out the video below to see a detailed breakdown:
In a standard car heating system the heat is derived from the hot engine, so the heat put out by any 12-volt alternative is always going to pale in comparison. Even the most powerful 12-volt heater however, is no match for the heater your car rolled out of the factory with.
If you can look past the safety concerns and poor quality construction, the one advantage I do see is that they provide immediate heat.
Where the factory heater relies on the car engine to heat up, an electric heater can simply be plugged in and switched on. This means that you could theoretically pre-heat the car and defog the windscreen without waiting for the engine to heat up.
But if you do decide to buy and install a 150W heater that plugs into your cigarette lighter then you're a braver person than me and I hope you have good insurance. I couldn't find one with more than a 2.5 star average on Amazon.
2. 12-Volt Car Seat Warmers
Given the 12 volt fan heaters don't seem to work what are the other options for staying warm if your car heater isn't working.
Luckily, there are other 12-volt heating alternatives that also plug into the car’s cigarette lighter. The good news is that these products actually seem to be decent and work as expected.
Heated seat covers can be placed over your seat for you to sit on. They work by having a heating coil running through them. When pressed against your body these become nice and warm and can help keep your core warm when driving without a heater. The Healthmate Car Seat Warmer is a popular brand, has good ratings and is an affordable price.
They won't do anything for the passengers in your car or to defrost the windows though.
3. 12-Volt Electric Blankets
To keep you even warmer heated blankets could be an even better option than heated seat covers. They work by having a heating element running through the fabric that can warm you up but have the added benefit of being able to cover your body.
Like the seat warmers, the 12-volt electric blankets will warm the body more directly than the fan type heaters and might be the better option if you don’t need to heat the entire space or de-mist your windscreen. They also have good ratings and seem to work as intended without breaking easily.
They still aren't the highest quality products, but they should get your though a winter.
The downside of these is that they can be tedious and difficult to use when driving. But they are great for passengers.
4. Residential Electric Heaters
Another option is to pre-heat the car’s interior with a residential electric heater. These are the heaters that you would usually plug into the wall at home to use indoors.
They are much more powerful than their 12-volt cousins and will have your car toasty in a few short minutes.
This method will defrost your windows, melt the ice and snow from the outside of your vehicle, and keep you warm until the engine heats up.
This will only work prior to driving. You'll need to plug it in to your mains power with an extension chord and it's a good idea to get it running 20-30 minutes before you need to hop in your car in the morning. Some people even allow 1-2 hours if the weather is particularly cold.
You'll want to get a heater with a small form factor so it fits nicely in your car and you'll want to get one that outputs around 1,500 Watts so it puts out maximum heat. I like this small space heater at Amazon as it's high wattage, small form factor, has a fan that rotates and it has thousands of great reviews.
If you get one that only outputs 250-500 Watts it'll hardly do anything for the car – although these lower power ones can be pointed at the windshield to defrost it.
For safety’s sake, attach a timer and position the heater in the car where it isn’t going to melt anything.
Once you're ready to drive unplug the heater, store away your extension chord and you're good to go.
If you want to stay warm on the go then you'll need to use one of the other methods we've mentioned.
5. Portable Propane or Butane Heaters
Portable propane heaters are popular among van lifers. These devices use propane or butane canisters as a fuel source and require great care and caution if you decide to use one to heat your car – especially if you're on the move.
Propane heaters are safer to use as a pre-heat option rather than operating in a moving car. If you do decide to use a propane heater these are the minimum precautions to adhere to:
- Make sure yours has a low oxygen shutoff function
- Make sure yours has a tip-over shutoff function
- Make sure you open windows for ventilation
For a Butane Heater with the easy to use cans this PDD Outdoor Butane Heater at Amazon is a great compact and affordable heater that works great.
It's compatible with both butane cans and larger butane bottles which is a really nice feature especially if you want to run this for a decent amount of time.
For a Propane heater I recommend this Mr Heater Propane heater at Amazon. It's approved for indoor use and puts out a lot of heat – thus heating your car quickly.
The propane canister tucks away nicely and it's got a lot of very positive reviews. Well worth a look.
6. Engine Block Heaters
A working car heater still relies on hot engine coolant to supply the heat. If the engine fluids are frozen or sludgy you are going to have a difficult time getting anywhere, let alone getting warm.
An engine block heater is basically an electric blanket for your car’s engine. It is laid over the engine, under the hood, and plugged into a socket.
For those of us in colder climates, an engine block heater is an essential piece of gear that warms up the engine fluids before starting the vehicle. This prevents the damage caused from cold starts and will also reduce the time it takes to get you on the road in a cozy car.
7. Engine Coolant Heaters
If you have the budget or mechanical know-how, there are systems that use your car’s hot coolant as a heat source, just like the factory heater did. These systems are more expensive upfront but provide a more permanent, energy efficient solution than electric heaters.
These systems work in the same way as the vehicle’s original heating system does and might be the only option when the original heater core is unfixable or the parts needed are unattainable.
They consist of a heater core, which needs to be connected to the car’s cooling system, and a fan, which needs to be wired to the car’s electrical system.
Hot coolant from the car’s cooling system flows into the heater core, which is essentially a small radiator. The fan blows air through the heater core thereby heating the air before it enters the interior.
While you will have to wait a short while for the engine to heat up, these systems will provide much more heat output than any 12-volt heater can hope to come close to. Another advantage is that these can be installed anywhere in your car that you can run the coolant and electrics to.
8. Create A Heater Using A Cooler
Just like people make homemade air conditioners using a cooler you can take the same idea and use it to create a portable heater.
First you'll want to install a fan into the lid of your cooler. If you're using this on your car ideally you'll want to use a battery or 12 volt fan – not one that runs off 110 or 240 Volts.
But instead of putting ice in your cooler to blow out cold air you'll want to put hot items in your cooler.
Hot bricks that you've baked in the over work great and so do hot water bottles or even non-insulated metal bottles filled with boiling water. Just make sure to cover the hot bricks in tea towels so it doesn't melt the plastic of your cooler.
Below are some instructions on how to make one of these cooler heaters.
A warm cooler can also be used to stop water from freezing in your car overnight.
If you don't want to make one yourself then you can buy an IcyBreeze Cooler which has the fan and everything pre-installed and runs off rechargeable batteries.
Now this is designed to be used with ice water but I don't see why you couldn't use it with hot water to create a portable heater that will work for a couple of hours in your car.
9. Use A Hot Water Bottle
Sometimes the simplest solutions are the best.
When at home fill up a hot water bottle with boiling water and then when it the car keep that hot water bottle under your clothing to keep you warm.
If you want to have multiple hot water bottles you could make multiple and keep them in your car in a heavily insulated cooler like a Yeti, which can keep things hot for hours at a time. Alternatively, you can wrap up the hot water bottle in blankets or clothes or have a kettle with you and refill your hot water bottle as needed when you have access to power.
10. Fix Your Car Heater Yourself
While a mechanic might quote you $1,000+ in order to fix your car heater there are a lot of common heater problems that can be diagnoses and fixed yourself. Below is a great video showing many of the common problems stopping your heater from working and what you can do to fix them.
Common issues you can diagnose and fix yourself include:
- Check you have enough coolant in the radiator and coolant reservoir
- Bad water pump
- Absence of thermostat or thermostat stuck open
- Blower motor resistor
- Blower motor is bad
- Clogged heater core
- Heater control valve
- Air stuck in coolant system
- Blend door actuator
If none of these work then you may need to see a mechanic or use one of the car heater alternatives mentioned above.
There are plenty of alternative car heaters out there to choose from to suit your specific needs. The 7 options outlined in this article all have their pros and cons but amongst them you are sure to find the right solution for you.
- 12-volt electric fan heaters do not provide much heat. Most are cheaply manufactured and will malfunction before long, posing a risk to your vehicle’s electronics and making them a fire hazard.
- Other 12-volt seat covers and blankets have a heating element running through them. They provide heat directly to the body.
- Residential electric heaters can be placed in the car for a brief period to pre-heat the inside.
- Portable butane or propane heaters are a good pre-heating option but must be used with extreme caution.
- A cooler heater or hot water bottle could provide you with heat without any big external power source.
- Engine coolant heaters provide the most heat. They work the same way a factory system works.
- Engine block heaters are used in more extreme cold. They heat the engine fluids before starting the vehicle.