[PDF] Reznor Unit Heater Install | HVACDirect If touched, the vent pipe and internal heater surfaces that are accessible from outside the heater will cause burns. Suspend the heater a minimum of 5 feet (1) above the floor. For best results, the heater should be placed with certain rules in mind. In general, a unit should be located from 8 to 12 feet (2.4-3) above the floor. Related searches for reznor heater wire diagram reznor heater thermostat wiringreznor 235 wiring diagramreznor heater schematicsunit heater wiring diagramwiring diagram reznor gas heatergas heater wiring diagramreznor serial number lookupreznor f165 diagram