Specialized controls - whether you need manual, electric or air: explosion-proof activators, thermostats, freeze stats, limit switches, steam traps, valves and piping, coated, stainless steel, or fiberglass housings - we can do it all. Large Down Blow door heaters are available with over 1,000,000 BTU and 15,000 CRM - threaded type or welded flange fittings. You tell us what you need and we will build it. Air Make-Up Systems - roof mounted or wall mounted. We do systems as small as 1000 CFM and as large as 400,000 CFM. Any type of duct-work - whether directional for a unit heater or with dampers, louvers and rain hoods to select your air source. Multiple heating coils - whatever your BTU or size requirements are, we can engineer an air make-up system with pressures to 250 PSIG and temperatures to 650 degrees Farenheit. AND REMEMBER - ALL WITH CAST IRON COILS! Grid Industrial Heating, Inc. P.O. Box 950 Salem, Ohio 44460 Phone: 330.332.9931 Fax: 330.332.0841 info@gridheating.com