5
6
3. Place the cover in a safe place and take care not to damage the plastic light pipe assembly
mounted inside the cover.
4. Locate the cables that connected the old thermostat to the HVAC unit.
5. Ensure you make a note of the color/label relationship and remove the wires from the
HVAC control panel.
6. Now locate the same two wires the colors which you chose to connect the
Thermostat
display unit
(refer to your notes mentioned in the display unit installation instruction).
7. Using bottom right grommet entry connect the same two wires to the terminals marked “Com Link”.
Again, either color to either screw terminal.
NOTE:
In order to maintain a good dust and bug seal pierce the grommets just enough to pull your
wires through. Do not remove grommet. Ensure that all wires and their insulation are in good condition.
Replace any wire that shows sign of aging and feels brittle to the touch.
POWER CONNECTION ///
USING 24V AC FROM THE HVAC UNIT
If you can get easy access to the HVAC unit’s transformer you may use this to power the base unit.
However please check the following before doing so:
1. That the transformer rating is not exceeded when you add the display load (approx 200mA).
2. That the transformer is not switched via other circuits and has a permanent primary feed
from the power line.
3. That the voltage does not exceed 27V AC.
NOTE:
If in doubt please use the power adapter supplied with the
Thermostat
Kit. To do this, simply
route the power wire through the lower left grommet into the housing and plug in the power jack.
CONNECTION TO HVAC UNIT ///
The following three diagrams cover heating only, cooling only, and heating/cooling combination
HVAC units. The notations used refer to most common notations used in HVAC wiring in the US.
The installer must verify that these notations do indeed adhere to the following:
■
“W”
refers to the connection to the heat relay
■
“Y”
refers to the connection to the cooling relay
■
“G”
refers to the connection to the fan relay.
■
“R”
refers to the connection to the 24V AC transformer.
■
“COMMON”
refers to the connection between the other terminal of the transformer
and all HVAC system relays.
1. Double check all your connections and ensure that the installation is neat and all
connections are secure.
2. You are now ready to perform the discovery and final set up procedure covered in the
main system manual.
3. Leave the cover of the base unit off until the whole system is operational.
4. Upon completion of the set up, replace the front cover and ensure that the light pipe assembly
on the inside of the cover is not damaged or detached.
COM LINK
24V AC
NO
COM NC
LINK
LINK
NO
COM NC
NO
COM NC
W
(HEAT RELAY)
R
24V AC
TRANSFORMER
Y
(COOL RELAY)
G
(FAN RELAY)
COM LINK
24V AC
NO
COM NC
LINK
LINK
NO
COM NC
NO
COM NC
R
24V AC
TRANSFORMER
Y
(COOL RELAY)
G
(FAN RELAY)
COM LINK
24V AC
POWER
JACK
POWER
JACK
POWER
JACK
NO
COM NC
LINK
NO
COM NC
NO
COM NC
W
(HEAT RELAY)
R
24V AC
TRANSFORMER
G
(FAN RELAY)
SINGLE STAGE HEATING/COOLING
SINGLE STAGE HEATING ONLY
SINGLE STAGE COOLING ONLY
TO DISPLAY UNIT
TO DISPLAY UNIT
TO DISPLAY UNIT
Summary of Contents for XWT380
Page 1: ...THERMOSTAT v1 0 ...
