Install Instructions
© COPYRIGHT 2010 PECO, INC. ALL RIGHTS RESERVED. P/N 70478 3220-2267 REV 00
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In case of difculty, try one of the following suggestions below.
If display screen is blank • Thermostat is not being powered • Check to assure connection between Common (C) and (RC) for 24 VAC.
• Check to assure that the metal jumper connects “RC” and “RH” (on
single transformer system only).
• Check to assure AA batteries are installed properly and are charged.
• Default Display is set to “4” (None) • Check Service Menu 520.
If display screen is blank AND system is running AC
power only
• Power harvesting is enabled without battery
support
• Install batteries and select “0” (disabled) in Service Menu 510 (to disable
Power Harvesting).
If keys do not allow manual entry • Keypad Lockout may be enabled • Access Service Menu 340. Within this menu, select option “0” to assure
there is no keypad lockout (so manual entry is enabled).
If Service Indicator (wrench) is on • Remote temperature sensors may not be
installed correctly or may be damaged.
• Check to assure that remote temperature sensor is connected properly.
Ensure that the system uses PECO-approved sensor(s).
Setpoint limits do not change • Heat or cool setpoint limit has been reached • Check range limits and deadband (see Service Menus 290, 300, 380).
• Keypad is locked • See item above
If no heating or cooling is running, but there is a call
for heat or cool (Heat/Cool appears on display) in
Auto mode
• Heating or cooling equipment is not operating • Check Service Menu 110 to assure that the correct option is selected to
match the system type.
• Check wiring, using output tests to verify (see Service Menus 600, 610,
620, 630, 640).
If heating and cooling system doesn’t respond • System type selection is incorrect • Check Service Menu 110 to assure that the correct option is selected to
match the system type.
If heating and cooling equipment are running at the
same time
• System type selection is incorrect • Check Service Menu 110 to assure that the correct option to match the
system type is selected.
• Heating and cooling wires are shorted together • Separate the heating and cooling wires, using output tests to verify (see
Service Menus 600, 610, 620, 630, 640).
Heat does not turn on (Heat is on continuously on
display)
• Heating equipment failure
• Loose or broken wire connection between
heating equipment and thermostat
• Check for 24 VAC at the equipment on the secondary side of the
transformer between the Power for Heating (RH) and the Common (C).
• Check to assure 24 VAC connection between heat terminal (W1) and
transformer Common (C). If 24 VAC is present, thermostat is functional.
Check heating equipment to nd cause of failure. If voltage is not
present, check wire connection between the heating equipment and the
thermostat.
If Demand Indicator light is red • Heating is occurring • No action is required.
If Demand Indicator light is green • Cooling is occurring • No action is required.
If Demand Indicator light is ashing • An error has occurred
• Remote sensor may be malfunctioning
• Check remote sensor wiring.
• Verify that the sensor(s) are PECO supported products.
If heat pump issues cool air in heat mode or warm air
in cool mode
• Changeover valve (B/O terminal) is not
congured to match the heat pump
• Check Service Menu 130 to assure that the changeover valve (B/O
terminal) is set to properly match the heat pump.
Cooling does not turn on (Cool is on display) in Auto
mode
• Cooling equipment failure
• Loose or broken wire between cooling
equipment and thermostat
• Check for 24 VAC at the equipment on the secondary side of the
transformer between the Power for Cooling (RC) and the Common (C).
• Check to assure 24 VAC connection between the cool terminal (Y1) and
transformer Common (C). If 24 VAC is present, thermostat is functional.
Check cooling equipment to nd cause of failure. If voltage is not
present, check the wire connection between the cooling equipment and
the thermostat.
If fan does not turn on when there is a demand for
heat
• System type may be incorrect • See Service Menu 110 and assure that the correct option is selected.
• Fan control may be incorrect • See Service Menu 120 and assure that the correct option is selected.
If heating system is running in the cool mode • System type selection is incorrect • Check Service Menu 110 to assure that the correct option is selected to
match the system type.
If heating equipment does not turn off and heat
temperature setting is set below room temperature
• Heating equipment is not a heat pump but
system type selected is heat pump
• Check Service Menu 110 to assure that the correct option is selected to
match the system type.
If the user cannot select the system setting for cool • System type is set to Heat only or Heat only
with fan
• Check Service Menu 110 to assure that the correct option is selected to
match the system type.
If the user cannot select the system setting for heat • System type is set to Cool only. • Check Service Menu 110 to assure that the correct option is selected to
match the system type.