Install Instructions

When radiant floor heating is installed, it is always the first stage of heating, followed by the heat

pump, and lastly any backup heating. This allows the floor to remain warm in the heating season.

EQUIPMENT SETTING 1HP 1HP/1AUX 1HP/2AUX 2HP 2HP/1AUX 2HP/2AUX

First stage heating Y1 W1 W1 Y1 W1 W1

Second stage heating - Y1 Y1 Y2 Y1 Y1

Third stage heating - - W2 - Y2 Y2

Fourth stage heating - - - - - W2

First stage cooling Y1 Y1 Y1 Y1 Y1 Y1

Second stage cooling - - - Y2 Y2 Y2

Fan G

Accessory 1 Choice of: Humidifier, Dehumidifier, HRV/ERV ventilator

Accessory 2 Reversing valve O or B.

O relay remains closed during heating operation.

B relay remains closed during cooling operation.

Heating Differentials

Each heating stage has an adjustable differential and time delay setting to determine when the stage

turns on. The heating stages Heat 4 to Heat 1 shut off are when they reach 1.5, 1.0, 0.5, and 0.0°F

(0.75, 0.5, 0.25, and 0.0°C) of the Heat To setting respectively.

Radiant Floor Heating

Radiant floor heating is operated differently than other heating types due to the large time delays to

heat and cool the slab. When Radiant Floor Heating is selected in the setup menu, the W1 relay oper-

ates using Pulse Width Modulation. This improves comfort for radiant systems with high mass floors.

• 100% on time at Heat To setting -1.5

• 50% on time at Heat To setting

• 0% on time at Heat To setting + 1.5

Room Sensor and Averaging

The room temperature can be measured using a combination of the built-in and auxiliary sensors.

• Built-in room sensor only

• Built-in room sensor with auxiliary room sensor(s) (temperature is averaged)

• Auxiliary room sensor only

Floor Sensor for Radiant Floor Heating

If a floor sensor is connected, floor minimum and maximum settings are available.

For a combination of air and floor temperature control, leave the internal air sensor on in the setup

menu. A floor minimum can be used to prevent a fast drop in temperature caused by receding solar

exposure. This operation is recommended for areas heated by afternoon sun through large windows.

When the sun sets, it can take a long time for the floors to get warm again. This may cause the room

to cool off too much in the early evening. A floor minimum setting can help with this condition by

maintaining a floor minimum temperature. Keep in mind the floor minimum temperature will override

the air temperature, and if set too high, may overheat the room.

A floor maximum is recommended for rooms with hardwood floors. Setting floor minimum and

maximum temperatures is a way of enhancing the comfort of the living space while protecting

floor coverings.

If there are more than one floor temperature sensors, the temperature is averaged.