Comfort-Aire HMB**V*1E SERIES - Manual (Page 14)

14
TROUBLESHOOTING
If the air handler fails to operate, check the following:
• Is the electric turned on?
• Is the thermostat operating properly?
• Are the blower compartment door(s) in place?
• Is the air handler disconnect closed?
• Has the circuit breaker tripped or the control board fuse
burned open?
• Are any manual reset switches open?
• Is the filter dirty or plugged?
• Is the LED on both control boards constantly ON? If
not, refer to Tables 2 or 3 to determine fault condition.
Blower Fan Wheel
Inspect the blower wheel blades for accumulations of dirt
and clean if necessary. Inspect mounting nut for tightness.
Blower Motor & Assembly
Inspect the blower assembly and motor mounting
brackets for tightness and corrosion. Correct deficiencies
if necessary. The blower motor contains sealed bearings
and under normal operating conditions, no maintenance
is necessary for the life of the equipment.
Cooling Coil
Inspect the cooling coil, drain pan, and condensate drain
at the beginning of each cooling season for cleanliness.
Clean these components as necessary using a mild
detergent and water. After cleaning, flush the coil, drain
pan, and condensate drain to remove all detergent.
IMPORTANT: Use caution when cleaning these
components so that the insulation does not get wet.
RED LED (AN2) DIAGNOSTIC
OFF Control Fault (No Power)
Flash Blower Fault
ON Normal Operation
Table 2. Air handler Control Board Fault Conditions
Table 3. Motor Control Board Fault Conditions
DIAGNOSTIC
GREEN
LED
RED
LED
Fixed
Speed
Furnaces
Control Fault (No Power) Off Off
Normal Operation On On
Motor Fault On Flash
Twin Fault (no motor fault) Flash On
Communications Fault Flash Flash
Variable
Speed
Furnaces
Control Fault (No Power) Off Off
Normal Operation On On
Motor Fault On Flash
Communications Fault Flash Flash