Troubleshooting; Specifications - Aprilaire 8920W Safety & Installation Instructions

TROUBLESHOOTING

DISPLAY IS BLANK
If Power LED is not illuminated at the
equipment control module check the
following:
• Check circuit breaker and reset if
necessary
• Make sure power switch at heating &
cooling system is on
• Make sure furnace door is closed securely
HEATING SYSTEM DOES NOT RESPOND
("HEATING" APPEARS ON SCREEN)
• Check for 24VAC at the equipment on the
secondary side of the transformer between
power and common If voltage is not
present, check the heating equipment to
find the cause of the problem.
• Check for 24VAC between the heat terminal
(W) and the transformer common If 24VAC
is present, the thermostat is functional
Check the heating equipment to find the
cause of the problem
• Check for loose or broken wires between
the thermostat and the heating equipment
COOLING SYSTEM DOES NOT RESPOND
("COOLING" APPEARS ON SCREEN)
• Check for 24VAC at the equipment on the
secondary side of the transformer between
power and common If voltage is not
present, check the cooling equipment to
find the cause of the problem
• Check for 24VAC between the cooling
terminal (Y) and the transformer common
If 24VAC is present, the thermostat is
functional Check the cooling system to
find the cause of the problem.
• Check for loose or broken wires between
the thermostat and the cooling equipment
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FAN DOES NOT TURN ON IN A CALL FOR HEAT
• Check Installer Setting Fan Control In
Heating / Heat Pump Auxiliary Type, to
make sure the fan control is properly set to
match the type of system
HEAT PUMP ISSUES COOL AIR IN HEAT
MODE, OR WARM AIR IN COOL MODE
• Check wiring at the terminal block to
confirm the reversing valve is connected to
the proper terminal O is active in cooling
and B is active in heating
HEAT/COOL BOTH ON AT SAME TIME
• Check Installer Setting Equipment Type, to
make sure it is set to match the installed
heating/cooling equipment
• Check to make sure heating and cooling
wires are not shorted together
HEATING EQUIPMENT IS RUNNING IN
COOL MODE
• Check Installer Setting Equipment Type, to
make sure it is set to match the installed
heating/cooling equipment
"HEATING" IS NOT DISPLAYED
• Check Installer Setting Control Setup is set
correctly
• Change the System Mode to Heat, and set
the temperature level above the current
room temperature
"COOLING" IS NOT DISPLAYED
• Check Installer Setting Control Setup is set
correctly
• Change the System Mode to Cool, and set
the temperature level below the current
room temperature

SPECIFICATIONS

ENVIRONMENT
Temperature (shipping)
Temperature thermostat (operating)
Temperature equipment control module
(operating)
Relative humidity
ELECTRICAL
Operating voltage
Current
CONTROL
Outdoor, Remote, Leaving and Return
temperature sensor
Room temperature measurement
Return and Leaving temperature measurement
Outdoor temperature measurement
Setpoint temperature range
Setpoint humidity range
-30° to 150°F (-34° to 65°C)
32° to 120°F (0° to 48°C)
32° to 158°F (0° to 70°C)
Operating: 5% to 90% RH (non-condensing)
24VAC (18–30VAC)
Maximum: 25A (total), 10A (single output)
Maximum surge current: 5A
Maximum distance: 300 feet
Display range: 32° to 99°F (0° to 40°C)
Display range: -40° to 160°F (-40° to 71°C)
Display range: -40° to 130°F (-40° to 55°C)
Heat: 40° to 90°F (4° to 32°C)
Cool: 50° to 99°F (10° to 37°C)
Humidification: 10% to 50% R.H.
Dehumidification: 40% to 90% R.H.
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