BTUH gas input. Sizes 30-125 are approved for residential application. All sizes are approved for commercial/industrial installations. Model UDAP heaters are designed for 82-83% thermal efficiency and are approved forc installation in the United States and Canada by the Canadian Standards Association (CSA). Reznor V3 Series unit heaters have a refreshing new appearance with a glossy white cabinet finish and less visible hardware. Each size cabinet is easily suspended from either 2 or 4 suspension points. Or, an optional hanger kit for Sizes 30-125 allows for ceiling mounting. The low voltage terminal strip on the outside of the cabinet makes connecting control wiring easy with no panels to remove. The addition of a “G” terminal to the strip, along with the new design of the circuit board, allows for fan only operation (without adding relays). All units have a factory installed gas line nipple to the exterior of the cabinet for easy gas service connection. The preeminent new internal feature is the Tcore2 ® heat exchanger and single burner combustion system. Other standard features include a single-stage gas valve, multi-try direct spark ignition with 100% lockout, pressure switch to verify vent flow, resiliently isolated venter motor, venter wheel with improved housing, resiliently isolated axial fan and motor assembly, and a high temperature limit control. Sizes 30-125 also include a flame rollout safety switch. Operation is controlled through an integrated circuit board. The circuit board monitors heater operation and has LED diagnostic indicator lights to identify abnormalities in control functions. The V3 Series unit heaters are designed to provide all the features you expect in a Reznor heater plus improved efficiency, easier installation, and a new look ~ both inside and out. Look for the unique white unit with no visible front and bottom hardware, deep red louvers, black side handle, and angled corner to know you have a genuine Reznor unit by Thomas & Betts. 50-60°F Rise range. Tcore2 ® titanium stabilized aluminized steel heat exchanger. Patented** Tcore2 ® single burner combustion system including a one-piece burner assembly. 115/1/60 Supply voltage. 115 Volt open fan motor with internal overload protection. Transformer for 24-volt controls. Integrated circuit board with diagnostic indicator lights. Multi-try direct spark ignition with 100% lockout. Fan relay (included on the circuit board). Single-stage natural gas valve (field adjustable for operation to 9,000 ft. elevation***). Vibration/noise isolated fan and venter motors ~ designed for low noise operation. 2-pt and 4-pt Suspension ~ standard on all sizes. External terminal strip for 24-volt wiring. External gas connection. Full fan guard ~ engineered for safety.