High Altitude Application; Testing Ignition Control Module - Daikin APGM3 Service And Troubleshooting

SERVICING
If the pressure switch opens after the gas valve has been
energized, the control will de-energize the gas valve and
run the indoor blower through the heat off delay. The
inducer stays on until the pressure switch re-closes. Then
the control makes another ignition attempt.
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 wires from the electrical terminals.
2. Using a VOM check from Common to NO (Normally
Open) - should read open.
If switch reads as noted proceed to Step 3, otherwise
replace control.
3. Remove the pressure control hose from the control
and interconnect with a digital manometer as shown:
Reconnect wires to the Common and NO terminals.
With Power ON:
Line voltage now present.
4. Energize furnace for heating cycle. The induced
draft blower motor will begin to run. The manometer
should read approximately -1.2" ± 0.3" W.C with no
combustion.
5. Remove and check the two electrical wires and using
the VOM check from Common to NO (Normally
Open), it should read closed (with I.D. motor running).
If not as above, replace pressure control.
WARNING
.
WARNING
6. Reconnect all wires to the control and place in heating
cycle.
7. As the unit fires on high stage, the manometer
negative pressure will drop to -1.0" ± 0.3" W.C.
8. If not as listed, replace control.
NOTE: The pressure switch must be mounted with the
diaphragm in a vertical position.

High Altitude Application

High Altitude Derate - U.S. Installations Only
IMPORTANT NOTE: The gas/electric units naturally
derate with altitude. Do not attempt to increase the
firing rate by changing orifices or increasing the
manifold pressure. This can cause poor combustion
and equipment failure. At all altitudes, the manifold
pressure must be within 0.3 inches W.C. of that listed
on the nameplate for the fuel used. At all altitudes
and with either fuel, the air temperature rise must be
within the range listed on the unit nameplate. Refer
to the Installation Manual provided with the LP kit for
conversion from natural gas to propane gas and for
altitude adjustments.
When this package unit is installed at high altitude, the
appropriate High Altitude orifice kit must be installed. As
altitude increases, there is a natural reduction in the density
of both the gas fuel and combustion air. This kit will provide
the proper design certified input rate within the specified
altitude range. High altitude kits are not approved for use in
Canada. For installations above 2,000 feet, use kit HA-03.
The HA-03 kit is used for both Natural and LP gas at high
altitudes.
Use LPM-08 (2 stage heat models) or LPM-07 (1 stage
heat models) propane conversion kit for propane
Mode conversions at altitudes below 2000 feet. Natural gas
installations below 2000 feet do not require a kit.
For propane conversions above 2000 feet, high altitude kit
HA-03 is required in addition to the propane conversion kit.

Testing Ignition Control Module

NOTE: Failure to earth ground the unit, or a high
resistance connection in the ground may cause the
control to lockout due to failure to flame sense.
To avoid personal injury or death due to electric shock,
wiring to the unit must be properly grounded. Disconnect
power before installing or servicing.
NOTE: The flash rate is 0.25 seconds on, 0.25 seconds
off, with a 2-second pause between codes.
WARNING
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