Espar’s Hydronic Coolant Air Heaters are typically tied in to the vehicles coolant system. These heaters can both pre-heat the engine coolant to allow for effective vehicle starting in extreme climates. With some modifications, vehicles can be configured to allow for warming the passenger compartment through the existing vehicle heating system, allowing the Hydronic heaters to pre-heat both the engine and passenger compartment.  

Additionally, with the addition of an Artic Fox Fuel and Fluid Warmers, Espar Hydronic heaters can be used to pre-heat both hydraulic and fuel systems on heavy equipment.

The following are low and high output settings on standard Espar Hydronic models

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  Low output High output
Hydronic 4 8,200 btu/hr 14,700 btu/hr
Hydronic 5 8,200 btu/hr 17,100 btu/hr
Hydronic MII – 8 5,118 btu/hr 27,297 btu/hr
Hydronic MII – 10 5,118 btu/hr 32,415 btu/hr
Hydronic MII – 12 4,095 btu/hr 42,000 btu/hr
Hydronic 16 N/A 54,630 btu/hr
Hydronic 24 N/A 82,000 btu/hr
Hydronic 30 N/A 102,000 btu/hr
Hydronic 35 N/A 120,000 btu/hr


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