Block Heaters vs. Remote Starters

Should you use a block heater, a remote starter, or both?

While both block heaters and remote starters are used to warm up vehicles, they are different technologies performing different functions: block heaters warm up the engine prior to starting it, while remote starters start the car from a distance.

Here's a closer look at the difference between the two.

Block heater vs remote starter

Overall Findings

Block Heaters
  • Warm the engine, which can help reduce engine damage caused by starting it cold.

  • Prevent engine coolant from gelling, delivering heat to the radiator more quickly.

  • Prevent oil from thickening or turning into tar.

Remote Starters
  • Start engine from a distance.

  • Warm the interior, lessoning or eliminating time spent driving in a cold vehicle.

  • Do not protect engine from risks of starting cold.

Block heaters are useful in very cold situations, as they help to warm the engine prior to starting it. This helps reduce damage caused by starting an engine in freezing temperatures. Remote starters, on the other hand, simply start the engine from a distance, allowing you to wait from a warm environment as the car interior warms up.

Use Cases: Engine Maintenance vs. Remote Convenience

Block Heaters
  • Meant to keep engine and peripheral components warm during dangerously cold temperatures.

  • Can prevent damage caused by overly cold engine startup.

Remote Starters
  • Allows you to start and warm up car from a distance.

  • Does not affect engine performance or protect against damage.

Block heaters are electric heating elements that prevent engine coolant from gelling. It's important to keep coolant as fluid as possible because gelled coolant is colder and therefore has trouble dissipating heat from the engine to the radiator. In extremely cold temperatures block heaters can help prevent oil from thickening and turning into tar. This task is less important, but it can cut down on engine wear. It also allows older engines to operate closer to peak efficiency without needing to warm up. And it means less time sitting in a cold car waiting to get warm.

Remote starters allow you to start the engine from a distance. The idea is that you don't have to wait inside the car while the interior warms up. You just have to make sure your car's climate controls are the right settings. The main benefit of a remote starter is comfort and convenience, rather than engine care and maintenance. A remote starter will not prevent damage if the weather gets cold enough to gel or freeze engine coolant.

Engine Maintenance: Block Heaters Keep Things Moving

Block Heaters
  • Help keep parts warm, prolonging life of engine.

Remote Starters
  • Does nothing to prolong life of engine.

If you park your car outside, and the temperature dips low enough to gel antifreeze or turn oil into thick sludge, then a remote starter won’t do you any good. Even if the remote starter manages to start your engine in extreme cold, it may still suffer damage as it warms up. If you have a heated garage, then a remote starter can still be of use, but it's important to avoid running a car inside a garage that is not properly ventilated, as doing so could lead to deadly carbon monoxide buildup.

Block heaters can prevent engine damage in extremely cold weather for a relatively low cost. Certain block heaters, specifically the ones that heat up the engine coolant, can also make you more comfortable during your commute by quickly providing warm air from the radiator.

Although remote starters are useful in that they allow you to warm up your car without going outside, it’s important to note that they’re most useful in circumstances where it isn’t cold enough to warrant a block heater, but it is still cold enough that jumping into an unheated car would be uncomfortable.

Types of Engine and Block Heaters

There are a few different types of engine heaters, some of which are not necessarily block heaters.

  • Oil heater: Heats the oil rather than the engine block. Best for climates where it doesn't get too cold.
  • In-line coolant heater: Warms the coolant to deliver heat to the radiator more quickly.
  • Contact heater: Transfers heat directly to the block via physical contact.
  • Heater blanket: Warms up the entire engine compartment.

How Oil Heaters Work

Oil heaters are heating elements that are installed in place of the dipstick or attached to the bottom of the oil pan. The heat they emit keeps the engine oil loose and warm, preventing engine damage and improving gas mileage.

These types of heaters work fine, and they’re great if you live in an especially cold area, but they don’t do anything to make you more comfortable, if that’s your primary concern.

How In-Line Coolant Heaters Work

The coolant is used to deliver warm air to the car's interior. In cold weather it can take some time for the coolant to absorb and dissipate heat from the engine, which is then used to warm the inside of the car. In-line coolant heaters expedite this process by installing a heater directly into the radiator hose.

How Contact Block Heaters Work

Contact heaters bolt to the engine, usually to the block, and heat the engine via conduction. They're somewhat similar to oil heaters that are fixed to the oil pan, and can heat up both the coolant and the oil. In extremely cold environments, block heaters help to keep the engine oil and coolant more fluid, preventing catastrophic engine damage. They are not necessary in more temperate climates.

How Heater Blankets Work

Heater blankets are essentially big pads with resistive heating elements woven into them. They don’t directly heat up the engine or its fluids, but they do radiate heat into the engine. These, too, are helpful in freezing climates where the damage risk of starting an engine in the cold is high.

Other Electric Car Heater Options

You can connect a block heater to an electrical outlet timer with a remote starter. While somewhat involved, this solution allows you to start the car from a distance while also pre-warming the engine to reduce wear and tear.

Plug-in electric car heaters are another way to warm up the inside of a car before stepping into it, but you need a garage or access to an electrical outlet to run them. Nonetheless, it is a more efficient method than running the engine via a remote starter. Depending on the source of electricity where you live, it may also be better for the environment. However, you must be careful about the type of heater you use, as most residential space heaters aren't safe to use in cars.