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SERVICE AND TECHNICAL SUPPORT MANUAL
Gas Furnace: N9MSB
Specifications subject to change without notice.
440 04 4413 03
13
Checklist
1. Put away tools and instruments. Clean up debris.
2. Verify that the jumper is removed from the TEST/TWIN
terminal. Verify that there is nothing plugged into the PLT
connector.
NOTE
: If there is a jumper connector plugged into PLT, remove
)
3. Verify that the Blower/Heat Off Delay jumpers are set as
desired. (See
)
4. Verify that there are no unsealed openings in the blower
shelf or casing.
5. Verify that the blower (lower door in upflow position) and
control (“Main” or upper door in upflow position) doors
are properly installed.
6. Verify that the Status LED heartbeat (bright
−
dim). If not,
check that the power supply is energized and that the
blower door is secure. See
to interpret
diagnostic codes
.
7. Cycle test furnace with room thermostat to be sure that it
operates properly with the room thermostat. Check all
modes including Heat, Cool and Fan.
8. Check operation of accessories per manufacturer’s
instructions.
9. Review Home Owner’s Information with owner.
10. Attach entire literature packet to furnace.