How many watts is a Subaru block heater?
Most Subaru engine block heaters used in North American models draw about 400 watts when connected to a standard 120-volt outlet, though some variants and regional kits may use higher or lower values. The exact wattage varies by model and market, so check the label or manual for your vehicle.
Block heaters are a common feature in cold climates, designed to pre-warm the engine and reduce wear during cold starts. This article explains the typical wattage you’ll encounter, how to verify the rating on your specific Subaru, and practical guidance for using a block heater safely and effectively.
Typical wattage you may encounter
Block heater wattage is not uniform across all Subaru models or regions. The most common configuration is a 400-watt heater connected to a 120-volt supply. Some vehicles offered in colder markets or with optional upgrade kits may use a higher wattage to speed up warming, while older or budget configurations may use lower wattage. The exact specification will usually be listed on the heater’s label or in the owner's manual.
- Common factory-installed: about 400 watts (120-volt systems) for many North American Subaru models.
- Higher-wattage variants: some regional or optional kits may use 600 watts to achieve faster preheating.
- Uncommon higher-end options: up to 800 watts in select aftermarket or specialized configurations, though this is not typical for standard Subaru equipment.
For precise wattage, consult your vehicle’s documentation or inspect the power rating on the heater itself. This ensures you use the correct outlet, cord, and timer settings.
How to verify the wattage on your Subaru
To confirm the exact wattage of your block heater, follow these steps:
- Locate the block heater and its power cord, usually near the engine block or on the heater element itself. Look for a label that lists the power rating (for example, "400W / 120V").
- Check the owner’s manual or Subaru dealer service literature for your model/year’s specifications.
- If the label is unclear or missing, contact Subaru customer support or your local dealer with your VIN to obtain the exact heater rating.
- Optionally, measure the current draw with a watt-meter when plugged into a known 120V outlet to estimate wattage, though this should be done safely and with the engine and heater unplugged during setup.
Knowing the precise wattage helps you select the right extension cords, power strips, and timers, and prevents overloading residential circuits.
Practical usage tips
Most users in cold climates set a block heater to run for 1–3 hours before starting a vehicle, depending on ambient temperatures and engine size. Use a timer to avoid leaving the heater on longer than necessary, protect electrical outlets from moisture, and ensure cords are rated for outdoor use.
Summary
The typical Subaru block heater in North America is rated at about 400 watts on a 120V circuit. Some markets or upgrade options may employ higher wattages (600–800W) for faster preheating. Always verify the exact rating on the heater label or in the owner’s manual, and use proper outdoor-rated cords and timers for safe operation in cold weather.
Do Subaru's have block heaters?
HOW DOES IT WORK EXACTLY? Once installed by your Subaru Dealer, the Block Heater should be plugged into a regular 110V electrical outlet early in the morning. This can be accomplished comfortably by having it plugged into a timer the night before, allowing the Block Heater to come on as early as 4.00 – 5.00 a.m.
Does it hurt to leave a block heater plugged in all night?
no harm other than your wallet. by factory specs the block heater its for the oil and its set for 80 degrees temperature so you could leave it plugged its 15 days and the temperature will not go above 80 degrees.
How many watts does a vehicle block heater use?
The power draw can range between 500W-5000W depending on the type of vehicle. For example, 5 and 6L diesel engines have factory installed block heaters that have an estimated minimum wattage draw of 1000W. For vehicles with 4 L engines, the block heaters installed could range between 500W to 1000W.
How many watts is the Subaru block heater?
400 watt, 115 volt heater warms engine coolant to promote easier starting in extreme cold conditions.
