How It Works Four-Pipe Unit Two-Pipe Unit with Electric Heat Two-Pipe Unit

Advantages for the Building Owner
Advantages for the Contractor
Sequence of Operation



This unit has a bypass duct in which the electric heater is located, and utilizes face and bypass damper control.

When the room thermostat senses a drop in temperature during cooling, the face dampers close (interrupting cooling) and the bypass damper opens. In the Òdead bandÓ range of the room thermostat, neither cooling nor heating takes place.

On a further drop in room temperature, the contactor closes and the electric heater is energized.

 Two-Pipe Unit with Electric Heat - Cool Two-Pipe Unit with Electric Heat - Heat


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