Most block heating technology employs natural convection within the engine block’s system to drive circulation—more commonly known as thermosiphon. This program promotes the replacement of thermosiphon style engine block heaters with pump driven circulation units, which reduces overall block temperature. Because it also decreases the heat transfer rate from the block to the environment, it can reduce overall block heater energy consumption, which is tied to the circulation method.
Because thermosiphon heaters require temperature variation to drive circulation warmer coolant rises to the top of the block with cooler coolant descending to the lower sections of the block. The coolant in the lower portions of the block must meet the minimum block temp requirements, which means the coolant in the upper parts of the block will exceed the minimum temperature requirements. A pump driven heater does not require temperature difference to drive flow. The coolant temperature is more uniform throughout the block. This reduces the overall average block temperature and minimizes the driving force affecting heat transfer.
Click here (PDF) for more details and to print a Standby Generator Block Heater Program Incentive Agreement. Please note: you can fill out this form online prior to printing.