Engine Block Heaters: A Winning Tool for Winter Weather

Despite Canadians having owned a personal vehicle for about a century now, you still won’t find a vehicle with an engine and battery impervious to cold.

During the coldest months, engine oil thickens, which affects how quickly your engine can start and then create heat. Modern vehicles use engine warming technology and may even come with a remote starter you can activate using your phone. However, for older models, an engine block heater is an inexpensive option.

What Is an Engine Block?

The engine block is manufactured from aluminum or cast iron. It contains the cylinders and serves as the foundation for all parts of your engine. By heating this component in winter, you can warm up the fluids that need to circulate so your engine can turn on easily and quickly.

An engine, especially in older cars, that spends most days and nights in sub-zero temperatures risks damage over time if it doesn’t have assistance with starting.

How Do Block Heaters Work?

An engine block heater uses electricity to keep your engine warm. Most designs rely on a constant 110 V connection to household electricity, so you’ll need an extension cord to plug it into an outlet. For safety reasons, use an extension cord approved for outdoor use.

You’ll find two main categories for block heaters: those that warm the coolant, and those that warm the engine oil.

Warming the Coolant

This is the more common design. Coolant runs through your engine to both cool and warm its components. Without it, your engine could reach a mind-blowing 2204 °C. Despite its name, coolant carries heat. During winter, part of this liquid flows through the heater core, which releases heat to warm the vehicle cabin.

A coolant engine block heater helps to keep the engine warm. Many engines can accommodate one, but it requires professional installation. The big bonus with a coolant engine block heater? Your cabin will warm up fast.

Warming the Engine Oil

Another common type of block heater warms the engine oil, either externally on the oil pan or internally through the dipstick tube.

Warm engine oil circulates through the engine more easily. However, because it doesn’t warm the coolant, your cabin won’t receive heat as quickly, making those first five minutes of winter driving a little chilly.

Other Types of Heating for Your Engine

If you want to forego a block heater install, or your car already comes with engine warming technology, there are two other options to consider when temperatures really drop.

Engine Warming Blanket

Whereas coolant block heaters require installation, engine oil heaters and engine warming blankets do not. An engine warming blanket is placed over the engine and works much like an electric blanket. Drivers living in climates with occasional deep drops in temperature might prefer this option.

Battery Blanket

As the name suggests, this accessory wraps itself around your vehicle’s battery. By keeping the battery’s fluids from freezing, a battery blanket helps your starter engine and alternator start in the morning, which makes it an excellent adjunct to an engine block heater, especially in Canadian locations where winter hangs out at -20 ˚C and colder.

Which Block Heater Works Best?

Which type of block heater is the best choice for you? The answer depends on a few different factors.

Winter Temperatures

If cold weather is rare but possible, you can probably get away with covering your motor with an engine blanket or using a dipstick heater on nights when you know the temperature is going to drop.

If you live in an area where “cold snap” means temperatures falling to about -20 ˚C, a coolant heater should suffice, because it will provide enough all-around heat to facilitate engine starts in the morning.

In freezing climates, an oil heater will reduce the time your motor’s internal assembly spends spinning before it’s properly coated and protected. Your cabin won’t warm as fast, but the mild discomfort is worth a well-coated engine.

You can also combine two types of heaters, which is recommended in areas of extreme cold.

Ease of Installation

Dipstick and oil pan block heaters and battery blankets are relatively easy to install yourself. The others are best left to a professional.

When Do You Not Need an Engine Block Heater?

There are a few situations where a block heater won’t help:

• The winters in your area are generally above -15 ˚C.
• Your car is newer and can handle starts in temperatures as low as -30 ˚C.
• You don’t have access to an electrical outlet.
• You park your car inside a garage.

To have your vehicle assessed for a block heater, visit your local NAPA AUTOPRO store, where one of our friendly technicians will be happy to advise you.