AprilAire Model 8052 Outdoor Temperature Sensor — Installation Instructions

Installation instructions for the AprilAire Model 8052 Outdoor Temperature Sensor, an optional accessory used with compatible AprilAire thermostats to provide outdoor temperature readings for advanced HVAC control logic.

Note: If an AprilAire AHC (Automatic Humidity Control) module is to be installed, do not wire a separate outdoor temperature sensor — the AHC uses its own outdoor temperature sensor, which can be read by the thermostat.

Mounting the Sensor

1. Locate the sensor on the North side of the building if possible. East and West are acceptable locations as long as the sensor will not be exposed to direct sunlight.
2. Mount above the anticipated snow line.
3. Mount at least 3 feet away from exhaust vents and condensing units.
4. Maximum wire length from sensor to thermostat is 300 feet.
5. Under a soffit or under a wall overhang are recommended mounting areas.
6. Follow any additional location requirements found in the sensor's own installation instructions.

Wiring the Sensor

2. Run a 2-wire cable from the sensor to the thermostat.

Caution: Do not run the sensor wire alongside line voltage (120 VAC) or higher voltage lines, as this can cause erratic readings.

3. Before connecting to the ODT and CIR GND terminals, take a resistance measurement to verify the sensor is properly installed. Use an ohmmeter to measure the resistance (kΩ) of the sensor — measure the wires at the thermostat to account for wire splices. The resistance reading will depend on outdoor temperature (see table below).
4. Wire the sensor to the thermostat: strip 1/4" of insulation from the two sensor wires and connect them to the ODT and CIR GND terminals. The wiring is not polarity-sensitive — either wire can go to either terminal.

Sensor Resistance Table

Wiring Diagram Reference

The sensor's two wires connect to the ODT and CIR GND terminals on the thermostat's terminal block (which also includes IDS, ZA, ZB, and C terminals). Wiring is not polarity-sensitive.