Unit installation

DCN: 141-00885-16 1/26/06 TZ40 Thermostat Manual 24
TZ40 Control Unit Installation
Location and Mounting
Install the TZ40 Control Unit in a protected, convenient, INDOOR location near the HVAC system or in a
service accessible area such as an equipment closet or garage.
Mount the Control Unit in a vertical position on a wall or sturdy structural member. The unit may be
mounted on the HVAC system but care should be taken to avoid the hot burner section or high vibration
areas.
Control unit wiring
The TZ40 HVAC Control Unit is connected to the HVAC system and to the Wall Display Unit as well as
the serial communications and power connections.
Control Unit to WDU wiring
Connect the WDU to the Control Unit with existing thermostat wiring in retrofit installations. For new
installs, 22/24 GA twisted pair, typically Cat3 or Cat 5 wiring is preferred.
CAUTION!
Be careful to not miswire the Wall Display Unit to Control Unit connections as damage may result.
Control Unit to HVAC System wiring
Electrically, the Control Unit looks like a standard thermostat to your HVAC system. All connections to
the HVAC system are made at the normal thermostat connections on the HVAC unit.
You are advised to refer to your HVAC system’s documentation for specific information on its thermostat
connections and setup requirements. You must know the following:
1. HVAC system type: Gas, Electric, Heat Pump, Radiant, Hydronic
2. Fan requirement: No fan with Heat or Fan with Heat
3. For Heat Pump systems: Changeover with cool or with heat. (O or B connection)
Note on retrofit wiring. You may note (and be sure to note on the wiring form) that you have additional
wires when you disconnect your old thermostat. Usually these wires are for auxiliary functions such as
filter or trouble indicators. For Heat Pump systems there may be emergency heat (EH) wiring or both O
and B changeover connections. These wires are not used in the TZ40 installation and, in most cases,
these extra wires are not required for normal HVAC system operation.
Refer to the following HVAC wiring diagrams for your type of HVAC system, Standard Or Heat Pump.
WDU
+12V
GND
DATA
CLK
J1
GND G
+12VDC +V
CLOCK C
DATA D
TS40
Control Unit