Troubleshooting Guide - Honeywell T7100D Product Data

T7100D,E,F MICROELECTRONIC COMMERCIAL THERMOSTATS AND Q7100A,C,D SUBBASES
B X
HEAT
CHANGEOVER
VALVE
COOL
CHANGEOVER
VALVE
1
CAUTION: EQUIPMENT DAMAGE. CAN BURN OUT THERMOSTAT. DO NOT CONNECT POWER TO THE D TERMINAL.
DO NOT PARALLEL SEVERAL THERMOSTATS FROM A SINGLE SOURCE UNLESS ISOLATION RELAYS ARE USED.
2 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
3 SELECT MODELS HAVE LEDS.
4 X4 NEEDS TO BE JUMPERED TO TERMINAL X.
Fig. 22. Typical hookup of Q7100C1073 in three-stage heat, one-stage cool heat pump system.

TROUBLESHOOTING GUIDE

Symptom
Display does not Thermostat is not being
come on. powered.
Temperature Room temperature display has
display is incorrect. been reconfigured.
Thermostat is configured for °F
or °C display.
Bad thermostat location.
Display shows two dashes and
a degree sign.
Temperature The upper or lower temperature
settings will not limits were reached.
change. (Example:
Cannot set the
heating higher or
the cooling lower.)
Heating does not No power to the thermostat.
come on.
O E G W3 Y2
EM. HT.
AUX. HT.
RELAY
RELAY
COMPRESSOR
FAN
CONTACTOR 2
RELAY
Includes remote temperature sensor, remote setback timer.
Possible Cause
• Check that X terminal is connected to the system transformer.
• Check for 24 Vac between X and R or RH terminals.
Enter Installer Setup 37 and reconfigure the display.
Enter Installer Setup 14 and reconfigure the display.
Relocate the thermostat.
Installer Setup 22 is set for remote sensing and the sensor is missing or
the circuit is open or shorted.
Check the temperature setpoints:
• Heating limits are 40 to 90°F (7 to 31°C).
• Cooling limits are 45 to 99°F (9 to 37°C).
• Check that X terminal is connected to the system transformer.
• Check for 24 Vac between X and R or RH terminals.
SUBBASE
Y1 X4 X1 X3
4
COMPRESSOR
CONTACTOR 1
EQUIPMENT
3 MONITOR 2
EQUIPMENT
MONITOR 1
— If missing 24 Vac:
— Check if the circuit breaker is tripped; if so, reset the circuit
breaker.
— Check if the system fuse is blown; if so, replace the fuse.
— Check if the power switch on the HVAC equipment is in the
Off position; if so, set to the On position.
— Check wiring between thermostat and HVAC equipment and
replace any broken wires and tighten any loose connections.
— If 24 Vac is present, proceed with troubleshooting.
— If missing 24 Vac:
— Check if the circuit breaker is tripped; if so, reset the circuit
breaker.
— Check if the system fuse is blown; if so, replace the fuse.
— Check if the system switch at the equipment is in the Off
position; if so, set to On position.
— Check wiring between thermostat and HVAC equipment and
replace any broken wires and tighten any loose connections.
— If 24 Vac is present, proceed with troubleshooting.
15
T T D D
R
REMOTE
TEMPERATURE
REMOTE
SENSOR
SETBACK
TIMER
1
L1
(HOT)
L2 2
M15325A
Action
(continued)
68-0163—3