Outdoor Air Temperature Sensor (Oats); Transformer Phasing; Damper Wiring - Lennox iHarmony 10C16 Installation And Setup Manual

Table 6. DATS Temperature / Resistance Chart
Sensor VDC (Volts)
°C °F (ohm)
37.8 100 5,819
40.6 105 5,193
43.4 110 4,654

Outdoor Air Temperature Sensor (OATS)

The optional outdoor air (temperature) sensor (OATS) (X2658) wiring dis-
tance to the iComfort S30 should not exceed 150 feet (45 meters) when
wired as specified in "Table 4. Terminals and Wiring Recommendations" on
page 4.
Installation of OATS must comply with the following requirements:
• Sensor wiring must be run to avoid touching or being close to high voltage
wiring and light ballast.
• Choose a protected outdoor location away from direct sunlight or other heat
sources (usually on the north side of the building).
• Ensure that water will neither collect on, nor wash over the sensor.
• Do not locate the sensor near driveways or similar heat-absorbing masses
which may reflect stored heat energy onto the sensor and send inaccurate
information to the thermostat.
• Locate the sensor away from attic and soffit vents, or furnace venting pipes.
• Do not locate the sensor directly above an air conditioner or heat pump.

Transformer Phasing

'The indoor unit and zone damper transformers must be in -phase since both
are connected to the damper control module. Follow the instructions below for
phasing both transformers.
1. Connect the damper control module indoor R and C to the indoor unit R
and C.
2. Connect the external 24VAC transformer to the damper control module
DMPR XFMR C terminal only. Check voltage from indoor R to External
XFMR wire R. If voltage is not phased then switch before connecting wires.
This will keep damaging voltage off of the control module.
» In -phase voltage will be the difference of both XFMR voltages approxi-
mately less than 5VAC.
» Out-of-phase voltage will be the sum of both XFMR voltages approxi-
mately greater than 50VAC.
3. Verify voltage between the damper control module indoor R and DPMR
XFMR R terminals after wires are connected.
Sensor
°C °F (ohm)
0.405 90.8 195 895
0.368 93.4 200 829
0.335
VDC (Volts)
Remove R to R wire when
testing. Replace wire when
0.072
0.067
Figure 3. Confirming Correct Transformer Phasing

Damper Wiring

See table 1 to determine the minimum damper transformer VA requirements
based on the number of zones being installed. If extended zone dampers
are used then see figure 2 for damper, transformer and zone relay wiring
requirements.
MAIN
POWER
Figure 4. Damper and Extended Damper Wiring Diagram
6
External 24VAC
Transformer
C
R
testing is completed.
Factory Default
R C
DMPRXFMR
SYS
DMPR
XFMR
XFMR
Damper Control
Module
Volt Meter
DAMPER TRANSFORMER – POWERS DAMPER CONTROL MODULE,
MAIN
POWER
Lennox Communicating
Furnace or Air
Handler
R i+ i− C
R i+ i− C
INDOOR