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The Real Reason To Use Block Heaters on Engines

When temperatures get cold things don’t move as well, and this includes your engine parts. An engine block heater can heat your engine up before you even start it and there are a few important reasons why you should use it.

Today, we’ll share why you should use block heaters on your engines. Let’s get started!

Everything You Need To Know About Your Block Heater

What Is a Block Heater?

A block heater is an electric heating element that is usually installed in the cooling system of an engine. When plugged in the heating element gets hot to warm the coolant. Natural convection currents will help the heat flow through the engine and heat the block and head.

People typically use block heaters in cold weather climates that experience extreme winter conditions. They warm the antifreeze, oil, and various internal components to make it easier to start your vehicle during freezing weather.

Vehicles with a block heater often have a short electrical plug sticking out. So Tesla and other EV drivers aren’t the only ones who have to plug their vehicles in occasionally. While it may not charge a car, there are several reasons drivers should consider using a block heater.

We have block heaters on all of our diesel engines, this includes our moterhome, diesel truck and even backhoe!

This is our block heater on our backhoe
This is our block heater on our backhoe

Why Should You Use a Block Heater?

The most important job of a block heater is to protect the engine and its many components from damage. A cold start in low temperatures can be incredibly harsh on the components. There’s a potential for damage as oil may not circulate and effectively lubricate parts during colder weather.

Block heaters can also help the engine start easier. Cold parts and oil are harder to turn over and with cold batteries, its possible you won’t be able to get started at all. If the engine is above freezing it will be much easier to turn over.

In addition to protecting the engine, block heaters pre-heat it, which helps it avoid running for extended periods before your vehicle warms us. A vehicle creates more pollution when it runs that long and cold. As a result, block heaters reduce emissions and are better for the environment as well.

Another reason you should use a block heater is they warm the cabin faster. The sooner your engine can reach its operating temperature, the sooner you’ll notice your vehicle’s cabin getting warmer. You won’t be one of those who start their car 10 or 15 minutes before they need to leave to avoid climbing into a cold vehicle. A car with a block heater could have a warm and toasty cabin in minutes.

Pro Tip: If you want to travel this winter, make sure you know The Truth About Winter RV Living.

Close up of a block heater on car engine
Protect your engine by warming it up with a block heater.

When Should You Use a Block Heater on Your Engine?

When to use a block heater on your engine will significantly depend on your vehicle and where you live. Typically, drivers start plugging in their block heaters once temperatures approach single digits. A car sitting in temperatures this low for several hours will get very cold and increase the chances of damage when a driver starts the engine.

You don’t need to leave your block heater on all the time, however. If you will not be starting the car you don’t need to heat the engine. Running it for an hour or so before starting the engine is usually enough to warm it up.

If you are experiencing cold temps and use your vehicle regularly you can even put the block heater on a timer so that it heats the engine every day at the same time.

What Types of Engines Could Benefit Most From a Block Heater?

While all engines can benefit from a block heater, diesel engines often benefit the most. A diesel engine depends on higher temperatures and compression than a gas engine to start and run. In addition, drivers who use non-synthetic oil or whose vehicle sits for extended periods greatly benefit from using a block heater.

block heater used on cold morning
If temperatures are low, before you jump into your car and drive off you will need to warm up your engine first. This is the block heater on our truck

How Long Do Block Heaters Take to Warm Up?

While it may be tempting to plug your vehicle in all night, it’s unnecessary. Depending on the block heater, it typically takes two to four hours for a block heater to do its job. Will it harm your vehicle if you leave it plugged in all night? Likely not. However, you’re wasting electricity and money by doing so. As long as your block heater has a few hours to work, it’ll have your engine ready for you to hit the road.

Do Block Heaters Use a Lot of Electricity?

Block heaters typically range from 750 to 1500 watts when running. While you may notice a slight increase in your electrical bill, it shouldn’t be shocking. The increase in your electric bill will significantly depend on how long you’re using your block heater and the rates for your utility company.

The increase you see will likely reflect the drop in temperatures. These conditions often increase electrical usage across the board from furnaces and other residential heating sources. However, the costs are a drop in the bucket compared to repair bills that often come from cold-weather damage.

Give your block heater two to four hours to heat your engine correctly.

Can I Leave Block Heaters Plugged in All Night?

You can leave your block heater on all night. It won’t do any harm or cause any damage to your engine. It will turn on and off throughout the night to keep your engine warm. Is it necessary to do this? No.

Leaving your block heater on all night wastes electricity and money. A block heater only needs two to four hours to heat your engine correctly. Leaving your block heater on for any longer than this is unnecessary and wasteful. Some drivers will use timers to automatically turn on their block heater at a specific hour to ensure plenty of time to warm their engine.

Can You Start Your Car While Block Heater Is Plugged in?

You can start your vehicle while the block heater is plugged in. However, you’ll want to be mindful to ensure that the extension cord is out of the way and won’t tangle in any moving parts.

Many drivers use the remote to start their vehicle before heading out to their car in the morning. Unplug the block heater before pulling away, or you could damage your block heater, the extension cord, and the electrical socket.

Pro Tip: Find out everything you need to know about your RV propane furnace before you need to use it this winter.

MAn wiping snow off vehicle attached to a block heater
Avoid wasting gas while warming up your engine by using a block heater instead of letting your car idle.

Can a Block Heater Overheat?

Block heaters are electrical appliances, and they’re not perfect. They can overheat and pose a fire risk. Ford issued a recall for their 2015-2016 Lincoln MKC due to overheating block heaters. You should always ensure that your block heater is free of wear and tear. In addition, properly size the extension cord running from the block heater to the electrical outlet.

WHY should you use your ENGINE BLOCK HEATER?! #gmc #chevrolet #engineblockheater

Do Block Heaters Really Work?

Block heaters do a fantastic job of ensuring your engine is ready to go when you need to use it during cold weather. They protect your vehicle, help you avoid wasting gas, and reduce unnecessary pollution. If you live in a cold-weather climate and want to protect your car, a block heater can work. However, if you live in an environment that rarely sees single-digit temperatures, you may not benefit much from a block heater.

Do you live in an area that would require the use of a block heater? Tell us about your experience in the comments!

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About Tom Morton

Tom, a Pacific Northwest native, is our technical genius. Born in Washington and raised in Alaska before settling in Michigan. He's the man who keeps our operation running, both figuratively and literally.

With a background in Electrical Engineering, Tom specializes in RV solar systems and lithium batteries. He made history as the first documented individual to use a Tesla battery module as an RV battery. Tom has personally assisted countless RVers with system installations and has educated thousands more through his videos and articles.

Cinematography is another of Tom's passions, showcased in his work on the Go North series. You can see his camera skills on display in The RVers TV show on Discovery Channel and PBS where he also stars as a co-host.

Tom's mechanical expertise extends beyond RVs to boats, planes, and all things mechanical. He's renowned for taking on maintenance and repair projects single-handedly and is often spotted underneath RVs, making him the technical backbone of our endeavors.

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Tuesday 24th of January 2023

They absolutely work and work well. I live in north Idaho. If I don't plug in under 40°, if my diesel starts, it billows white smoke and I need to drive several miles before it warms enough to stop. When plugged in, start right up and drive away with warm air coming from heater vents and no smoke. Love it. Rock on 7.3 Power Stroke!