Exhaust Heat Recovery System (EHRS)

The Basics

If you're like us, you find it frustrating that the cold Chicago Winters cause the first ten minutes of driving extremely detrimental to your mileage.  Until the engine reaches operational temperatures, the engine will work harder to generate much-needed heat.  Some of that heat is absorbed by the engine while the rest is shot out the exhaust. 

Thanks to the Exhaust Heat Recovery System (EHRS), some of that exhaust heat is captured and returned to the engine block.  This is done by sending the engine coolant back to the exhaust system and circulating it around the exhaust piping.  The heat from the exhaust is transferred to the coolant and used to heat the engine block.    As you can see in these charts, this results in a much shorter warm-up cycle and provides warm air to the cabin sooner.

The Details