Block heaters slowly pre-warm the engine before starting with a 200 to 600 watt 110volt heating element that is directly installed into the engine block. The reduced warm-up time can dramatically improve fuel economy, especially for short trips. It is recommended to put the heater on a timer that starts to heat the engine no more than about 3 hours before departure to avoid wasting electricity. The ultimate way to warm the engine faster and use less electrical power is to use the biggest block heater you can get your hands on, if one isn't enough use two. With multiple high wattage block heaters it becomes possible to warm the engine up faster and by default disbursing less heat into the surrounding environment. This cuts warm up times down to well under an hour.
Use immersion heaters that come in direct contact with engine coolant for best result. Only use stick on heaters as a last resort.
Not to be confused with high power coolant warmers, these usually require forced circulation and are fuel burning, 110 or 220 volt powered.
Instructions for mod
Refer to workshop manual and installation instructions for block heaters for installation methods
See how to's for some car specific instructions in the references at the bottom of this page.
The block heater shown to the right is a Kat's universal 400 watt block heater. It has 3/4 inch male pipe threads making it able to thread into lots of places.
Please enter your user name and any relevant data in the table
|User Name||Car Make, Model, Year||Cost of Mod||Time to Perform Mod||MPG Before Mod||MPG After Mod||MPG improvement guess||Instruction Link|
|Doax||Toyota, matrix, 2003||~$60 USD||~ 1.5 Hours||~4% (During winter less than 2MPG) no hard data just rough estimation.||Metro block heater install (not Doax's install)|
|TomO||1994 Honda Civc VX||$45 USD||< 1 Hours||43.12||44.93||4.2% (1.81 MPG) tank to tank data, but consistent route and driving||VX block heater install|
|Echo-Francis||Toyota Echo 2005||$50||2 Hours||Not tested. My engine defenitely start well when cold, i'm saving.||Echo-Francis Block Heater|
|Oil Pan 4||Chevy suburban diesel 84||$100 USD||3.5 Hours||FE effect untested. Was able to raise coolant temperature from -2'C to 22'C in 15 minutes with out running the engine||3500 watt universal fit coolant heater|
Problems / Consequences of mod
- User of electricity to heat car before traveling may outweigh the environmental and financial savings of modification
- Idle reduction
- Enter the much more efficient closed loop mode sooner.
- Remove frost so you can see, avoid crashing into objects.