Workers can use a trailer-mounted, indirect fired heater for more than preheating aggregate. Here, a maintenance crew at a Canadian mining operation warms the work area with direct heat.

Ground Heaters engineers advise producers not to think of the hydronic equipment only as a winter tool. They believe the greatest payback will be in spring and fall when temperatures can fall quickly after sunset. Hydronic heat may help producers speed strength development and help with faster form releases.

Additional dry heat

In the last few years, Ground Heaters has expanded from hyrdonic heat to a broader line of contractor-focused climate control devices. It began when the manufacturer added heater blower units to its ground thaw units.

Workers attach the heating tubes to standalone radiators. As the heated glycol passes through the exchanger, a fan draws cool air across the heated coils. It effectively heats a large floor area. A medium-sized unit can provide 100,000 BTU/hour at an air delivery rate of 1315 cfm.

Hydronic heaters, when coupled with these liquid-to-air heat exchangers, produce extremely clean hot air. In fact, tests have shown that hydronically heated work air is free of CO, CO2, H2O, smoke, and all other combustion byproducts.

For larger enclosed spaces, the manufacturer introduced a series of indirect fired forced air heaters. Contractors use these to heat unfinished buildings where concrete floors are poured. Unlike direct-fired heaters, these units don't introduce carbon dioxide into the air, eliminating a significant contributor of concrete surface crusting.

Several producers have adopted an indirect heater into their operations. They position the unit outside on the building and connect a vent tube from the unit to a window or door. When temperatures drop to a point where the plant heaters can't keep up, the producer just fires up the auxiliary heater to warm the work area.

The unit is designed to operate unattended, and it provides a workable alternative to steam injection of aggregate bins. The heated air is less moist than the steam and causes less damage to the plant's steel structure.

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