507715-01
Page 58 of 61
Issue 1716
Planned Service
A service technician should check the following items
during an annual inspection. Power to the unit must be
shut off for safety.
Fresh air grilles and louvers
(on the unit and in the
room where the furnace is installed) - Must be open and
unobstructed to provide combustion air.
Burners
- Must be inspected for rust, dirt, or signs of water.
Vent pipe
- Must be inspected for signs of water, cracked,
damaged or sagging pipe, or disconnected joints.
Unit appearance
- Must be inspected for rust, dirt, signs of
water, burnt or damaged wires, or components.
Blower access door
- Must be properly in place and
provide a seal between the return air and the room where
the furnace is installed.
Return air duct
- Must be properly attached and provide
an air seal to the unit.
Operating performance
- Unit must be observed during
operation to monitor proper performance of the unit and
the vent system.
Combustion gases
- Flue products should be analyzed
and compared to the unit specifications.
Problems detected during the inspection may make it
necessary to temporarily shut down the furnace until the
items can be repaired or replaced.
Instruct the homeowners to pay attention to their
furnace.
Situations can arise between annual furnace
inspections that may result in unsafe operation. For
instance, items innocently stored next to the furnace may
obstruct the combustion air supply. This could cause
incomplete combustion and the production of carbon
monoxide gas.
Table 14. Diagnostic Codes
LED Status
Fault Description
LED Off
No power to control or control hardware
fault detected
LED On
Normal operation
1 Flash
Flame present with gas valve off
2 Flashes
Pressure switch closed with inducer off
3 Flashes
Pressure switch open with inducer on
4 Flashes
High limit switch open
5 Flashes
Rollout switch open
6 Flashes
Pressure switch cycle lockout
7 Flashes
Lockout due to no ignition
8 Flashes
Lockout due to too many flame dropouts
9 Flashes
Incorrect line voltage phasing
Repair Parts List
The following repair parts are available through Comfort-Aire / Century dealers. When ordering parts, include the complete
furnace model number listed on the CSA nameplate. All service must be performed by a licensed professional installer (or
equivalent), service agency, or gas supplier.
Cabinet Parts
•
Upper Access Panel
•
Blower Access Panel
• Top Cap
Control Panel Parts
• Transformer
•
Integrated Control Board
•
Door Interlock Switch
Blower Parts
•
Blower Wheel
•
Motor
•
Motor Mounting Frame
•
Motor Capacitor
•
Blower Housing Cutoff Plate
Heating Parts
•
Flame Sensor
•
Heat Exchanger Assembly
•
Gas Manifold
•
Combustion Air Inducer
•
Gas Valve
•
Main Burner Cluster
•
Main Burner Orifices
•
Pressure Switch
•
Ignitor
•
Primary Limit Control
•
Flame Rollout Switches
