To Heat a new 148,000 sq-ft hanger facility that includes a large radiant floor and snow melt system for a same day, no excuses air shipment company that operates in a cold, snow bound area.  When hanger doors are ope, the heating system needs to keep workers and aircraft warm.  Outside, an area of tarmac must be snow free to aid maintenance and jet taxing maneuverability.


This project is a new installation of a huge 'in-floor' radiant heat system.  Four separate, 13,250 sq-ft slabs each zoned with a seven-manifold system consisting of 55,000 lineal feet of 3/4 inch radiant tubing for indoor heating and 10,000 sq-ft of snow-melted concrete slab were created. To power this system, two, stacked 1,500 MBH, fan-assisted, sealed-combustion, four-stage Pennant boilers were installed in a rack configuration. 
The stacked system design offers balanced airflow to each of the boiler's four firing stages. This permits each unit to continue operation without having to shut down the entire boiler system. It serves as a greatly simplified lead-lag heat source, if an ignition system of one unit should ever fail, the other takes over and maintains heat to the system.