Thermostat Features; Troubleshooting - Aprilaire 8800 Safety & Installation Instructions

THERMOSTAT fEATURES

• Large touch screen with adjustable backlight.
• Message center provides feedback and instructions.
• 7 day programmability or separately programmable
weekday/weekend schedules.
• Thermostat can be removed from the wall for easy
programming (batteries must be installed) .
• Front battery door access for fast, easy replacement.
• Displays room temperature, room humidity,
temperature setting, and optional outdoor temperature.
• Air filter, humidifier, dehumidifier, and HVAC service
indicators .
• Programmable fan control with fan circulation mode.
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• 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 .
• Battery back-up.
• System test mode.
• RS485 communications ready.
• Universal system compatibility.
• Configurable to control a humidifier or dehumidifier.

TROUblESHOOTINg

DISplAY IS blANK
• Check circuit breaker and reset if necessary.
• Make sure power switch at heating & cooling
system is on .
• Make sure furnace door is closed securely.
TEMpERATURE SETTINgS DO NOT CHANgE
Make sure heating and cooling temperatures are set to
acceptable ranges:
• Heat: 40° to 90°F (4° to 32°C).
• Cool: 50° to 99°F (10° to 37°C).
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 System Setting 09 (Fan Control), to make sure
the fan control is properly set to match the type of
system (see page 9) .
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 SW1 (Equipment Type), to make sure it is set
to match the installed heating/cooling equipment
(see page 8) .
• Check to make sure heating and cooling wires are
not shorted together .
HEATINg EQUIpMENT IS RUNNINg IN
COOl MODE
• Check SW1 (Equipment Type), to make sure it is set
to match the installed heating/cooling equipment
(see page 8) .
"HEATINg" IS NOT DISplAYED
• Check Installer System Setting number 05
(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 System Setting number 05
(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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