Thermostat Features; Troubleshooting - Aprilaire 8840 Safety & Installation Instructions

THERMOSTAT FEATURES

• Remote access and control over Wi-Fi
• Indoor air quality control
− Humidification automatic or manual control.
− Dehumidification.
− Event-Based™ air cleaning
− Ventilation with temperature and humidity limits
• Temperature control
• Heat Blast® raises the room temperature 3°F to 5°F
• One touch Away
• Support for optional wireless outdoor temperature sensor
• Large touch screen with adjustable backlight
• 7 day programmability
• Displays room temperature, room humidity, temperature setting, and optional outdoor
temperature
• Air filter, humidifier, dehumidifier, and HVAC service reminders.
• Programmable fan control with fan circulation mode
• Easy to use temperature control can override program schedule at any time
• Progressive recovery ensures proper temperature at the start of a program event
• Built in compressor protection prevents damage to your equipment
• System test mode
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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
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
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