Servicing; Checking Voltage; Checking Wiring; Checking Thermostat And Wiring - Daikin APGM3 Service And Troubleshooting

SERVICING

Checking Voltage

High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be
present. Failure to do so may cause property
damage, personal injury or death.
1. Remove doors, control panel cover, etc. from unit
being tested.
With power ON:
Line voltage now present.
2. Using a voltmeter, measure the voltage across
terminals L1 and L2 of the contactor.
3. No reading - indicates open wiring, open fuse(s) no
power or etc. from unit to fused disconnect service.
Repair as needed.
4. If incoming voltage is within the range listed in the
chart below, energize the unit.
5. Using a voltmeter, measure the voltage with the unit
starting and operating to determine if voltage is within
the range listed in the chart below.
6. If the voltage falls below the minimum voltage, check
the line wire size. Long runs of undersized wire can
cause low voltage. If the wire size is adequate, notify
the local power company regarding either low or high
voltage.
Unit Voltage
Rated Minimum Supply
Voltage Voltage
208/230V

Checking Wiring

High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be
present. Failure to do so may cause property
damage, personal injury or death.
1. Check wiring visually for signs of overheating,
damaged insulation and loose connections.
2. Use an ohmmeter to check continuity of any
suspected open wires.
WARNING
WARNING
Maximum Supply
Voltage
197 253
WARNING
3. If any wires must be replaced, replace with
comparable gauge and insulation thickness.
BRANCH CIRCUIT AMPACITY
SUPPLY WIRE LENGTH - FEET
200
150
100
50
Wiring Table

Checking Thermostat and Wiring

Thermostat Wiring: The maximum wire length for 18 AWG
thermostat wire is 100 feet.
Thermostat Wiring - Single Stage Models
Single Stage Heating & Cooling Thermostat
Thermostat Wiring - Two Stage Models
R
C
W1
W2
R C W1W2 G Y1 Y2
Two-Stage Heating with Two-Stage Cooling
Thermostat Diagram
Single Stage Thermostat - Two-Stage Models
To use a single stage thermostat, move jumper located
to the left of the terminal strip labeled "Stage Delay" from
NONE to "5" or "10" minutes. This selection will cause the
control to run on low stage for the selected time (5 or 10
minutes) then shift to HIGH STAGE. This option controls
both cooling and heating modes. If the jumper is not moved,
only low-stage cool and low-stage heat will operate.
15 20 25 30 35 40 45 50
6 4 4 4 3
8 6 6 4 4
10 8 8 6 6
14 12 10 10 8
From
Unit
Diagram
(
Thermostat
Two-Stage Heating
Y2
with
Two-Stage Cooling
Y1
G
Furnace Integrated
Control Module
3 2 2
4 3 3
6 4 4
8 6 6
14