5
6
9
10
7
8
Replacing Wiring Labels
A Quick Test
SC1600L/VL Wiring Diagrams
Heating Only
2-Wire,
Single Transformer
or Millivolt
Zone Valve/Damper Motor System
3-Wire, Zone Valve/Damper Motor System
2-Wire, Zone Valve/Damper Motor System
Note:
Differential temperature may need to be increased for
zone/damper systems (see Page 9).
ELECTRICAL SHOCK HAZARD
– Turn off power at the main service panel by removing
the fuse or switching the appropriate circuit breaker to the OFF position before
removing the existing thermostat.
IMPORTANT:
Thermostat installation must conform to local and national building and electrical
codes and ordinances.
Note:
Mount the thermostat about five feet above the floor. Do not mount the thermostat on
an outside wall, in direct sunlight, behind a door, or in an area affected by a vent or
duct.
1. Turn off power to the heating system by removing the fuse or switching off the appropriate circuit
breaker.
2. Move the
Off/Heat
switch into the
Off
position.
3. To remove cover, insert and twist a coin or screwdriver in the slots on the sides of the thermostat.
4. Put thermostat base against the wall where you plan to mount it (Be sure wires will feed through
the wire opening in the base of the thermostat).
5. Mark the placement of the mounting holes.
6. Set thermostat base and cover away from working area.
7. Using a 3/16” drill bit, drill holes in the places you have marked for mounting.
8. Use a hammer to tap supplied anchors in mounting holes.
9. Align thermostat base with mounting holes and feed the control wires through wire opening.
Old
New
Type
H, W, 4
W
Heating control
M, 4, RH, RS, R
R
Transformer, hot side
N/A
S1, S2
Optional remote sensor
Replace the old labels with the enclosed new
labels.
To Install Thermostat
To Install Thermostat (continued)
10. Use supplied screws to mount thermostat base to wall.
11. Insert stripped, labeled wires in matching wire terminals. See “Wiring Diagrams” section of this
manual (Page 8).
CAUTION!
: Be sure exposed portion of wires does not touch other wires.
12. Tighten screws on terminal block. Gently tug wire to be sure of proper connection. Double check
that each wire is connected to the proper terminal.
13. Insert two fresh “AA” alkaline batteries into thermostat, oriented in the direction shown on the
battery compartment.
14. Replace cover on thermostat by snapping it in place.
15. Turn on power to the system at the main service panel.
Installing and Changing Batteries
If your LCD is blank or displaying
LO BAT
, the batteries are not installed or need to be changed. We
suggest you change the batteries at least once a year, or whenever the
LO BAT
warning displays.
Note:
After installing new batteries, you have to reset the room temperature setting and the
differential setting.
1. Move the
Off/Heat
switch into the
Off
position.
2. Remove the cover, and install the two “AA” alkaline batteries. Proper battery installation is
important! Make sure the positive ends of the batteries match the positive terminals in the battery
compartment.
If the display is on, the batteries are installed properly.
Starting the Thermostat
1. Move the
Off/Heat
switch into the
Heat
position.
Setting the Temperature Differential
The default temperature differential is 1°. When your room temperature varies by 1°F, the thermostat
turns on your system. If you notice your system turning on and off too frequently, increase the
temperature differential.
1. Reset the thermostat by removing batteries for 10 seconds and then reinstall them.
2. For the first 10 seconds of operation, the temperature differential is displayed.
3. Press the or button to select desired setting.
Setting the Setpoint Temperature
1. Place
Off/Heat
switch in the
Heat
position.
2. Press the or button a single time to see the
current temperature
setting.
3. Press the or button until the
desired temperature
setpoint displays.
4. The new temperature setpoint is automatically saved in memory. After 5 seconds, the display
returns to showing the current room temperature.
Do not short jumper across terminals on the gas valve or at the system control to test installation.
Action:
Set the
Off/Heat
switch to
Heat
; press the
button until the set temperature is 3°F above
the room temperature.
Result:
The heating system should turn on; there may be a time delay depending on your
system.
Action:
Press the button until the set temperature is below the room temperature.
Result:
The heating system should turn off.
If the above
test was successful
, you have a proper installation.
If the above
test was unsuccessful
, double check that the wires are securely connected and are
connected to the proper terminals. Consult the troubleshooting section below.
Troubleshooting
Symptom
Remedy
The system is not turning on
Check batteries; display is blank when batteries are not present
or are dead.
LCD is blank, or displaying
LO BAT
Replace batteries, or make sure the existing ones are properly
installed.
Thermostat turns on and off too
frequently
Adjust temperature differential (see “Setting the Temperature
Differential”.
1. Remove cover from remote sensor housing.
2. Select an appropriate location for mounting the remote sensor.
3. Mount remote sensor unit using hardware provided.
4. Install two conductor shielded wires between remote sensor and thermostat. Shielded wire must be
used. Do not run remote sensor wire in conduit with other wires.
• Wire 1 should run between the S1 terminal on the thermostat and the S1 terminal on the remote sensor
• Wire 2 should run between the S2 terminal on the thermostat and the S2 terminal on the remote sensor
• Connect the shielding of the wire to the S2 terminal on the thermostat
5. Disable the main sensor on the thermostat by
cutting it from the circuit board.
S1
S2
W
G
R
Cut Thermistor from
circuit board
Use
appropriate
size, single
pole/double
throw relay
24
VAC
24
VAC
Remote Sensor Installation (Optional)
