Dip Switch For Emergency Thermostat - Mitsubishi Electric PAAA18AA1 Installation Manual

15.7. DIP switch for emergency thermostat

Using DIP switch SW01 settings on the relay board, you can select one of two modes—Test or Emergen-
cy—to operate in.
If DIP switch SW01-4 is set to ON, the PAA unit enters Test mode. While in Test mode, the installer can
use the push buttons on the control box user interface to set W1 and W2 to ON or OFF. See the "Control
box user interface" image below.
WARNING
To ensure proper and safe operation of the unit, do not leave the home while the Test
mode is running. Otherwise, results such as electric shock, fire or explosion may occur.
You can determine the initial (ON or OFF) state of the Test W1 and W2 heat signals in Test mode. Setting
DIP switch SW01-2 to ON turns the Test W1 signal ON immediately once the furnace is powered on.
Otherwise, the Test W1 signal will be OFF.
Setting DIP switch SW01-3 to ON turns the Test W2 signal ON immediately once the furnace is powered
on. Otherwise, the Test W2 signal will be OFF.
Steps to check the furnace operation in Test mode:
Step 1: Power off system if not already off.
Step 2: Wait for 3 minutes; this ensures that the unit is completely powered down.
Step 3: Set SW01-4 to ON for Test mode.
Step 4: Turn the furnace breaker ON. Ensure that the Mitsubishi Electric US, Inc. system breaker is OFF.
You are now in Test mode. Verify the Test mode indicator (red color) on the control box user interface is ON.
Step 5: Press W1 ON on the control box user interface to turn on the first stage of furnace heat. Verify that
the furnace fan turns on along with furnace heat.
Step 6: Press W2 ON on the control box user interface to turn on the second stage of furnace heat. Verify
that the furnace output increases. This is only applicable for furnaces with two stages. Single-stage furnace
shows no difference.
Step 7: Power down the furnace.
Step 8: Set SW01-4 to OFF to disable Test mode.
The PAA unit system enters emergency mode if power is still applied to the furnace and (a) the outdoor unit
loses power or (b) there is an error state that does not allow full system control.
If DIP switch SW01-4 is set to OFF, the NAT connected to the PAA unit control box controls the heat applied
to the furnace during an emergency mode failover.
© 2022 Mitsubishi Electric US, Inc.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
88 Specifications are subject to change without notice.