Checking Voltage; Checking Wiring; Checking Thermostat And Wiring; Indoor Blower Motor - Daikin M Series 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 Voltage Min. Supply
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
WARNING
WARNING
Max. Supply
Voltage Voltage
197 253
WARNING
suspected open wires.
3. If any wires must be replaced, replace with
comparable gauge and insulation thickness.
Branch Circuit Am-
pacity
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.
A/GPDM3
Terminal
Red
Green
Orange
White
Brown
Yellow
Blue
Line voltage now present
With power ON, thermostat calling for cooling
1. Use a voltmeter to check for 24 volts at thermostat
wires C and Y in the condensing unit control panel.
2. No voltage indicates trouble in the thermostat, wiring
or external transformer source.
3. Check the continuity of the thermostat and wiring.
Repair or replace as necessary.

Indoor Blower Motor

With power ON:
Line voltage now present
1. Set fan selector switch at thermostat to "ON"
position.
2. With voltmeter, check for 24 volts at wires C and G.
3. No voltage indicates the trouble is in the thermostat
or wiring.
4. Check the continuity of the thermostat and wiring.
Repair or replace as necessary.
15 20 25 30 35 40 45 50
6 4 4 4 3 3
8 6 6 4 4 4
10 8 8 6 6 6
14 12 10 10 8 8
24-48
Thermostat
R (24V)
G (fan)
O (Rev. Value)
W1 (Heat, 2nd)
W2 (Heat, 3rd)
Y (Cool)
C (24V Common)
WARNING
WARNING
2 2
3 3
4 4
6 6
17