ICM Controls SC 4811 General instructions

2 Heat/2 Cool
Auto Changeover
Hardwire
SC 4811
Electronic Thermostat
Installation, Operation & Application Guide
For more information on our complete range of American-made
products – plus wiring diagrams, troubleshooting tips and more,
visit us at www.icmcontrols.com
• Configurable
• 2-Stage Heat/2-Stage Cool Systems
• 2-Stage Heat Pump Systems
• Large Display With Backlight
• Selectable Fahrenheit or Celsius
• Compatible with Gas, Oil, or Electric
• SimpleSet™ Field Programming
• Status Indicator Light
• Relay Outputs
(minimum voltage drop in thermostat)
• Remote Sensor Compatible
• Ideally Suited for:
– Residential (New Construction/Replacement)
– Light Commercial

Table of Contents
PartsDiagram ..................................................................... 1
IconDescriptions................................................................... 2
Specifications...................................................................... 2
ImportantSafetyInformation ......................................................... 3
PackageContents/ToolsRequired...................................................... 3
ToRemoveExistingThermostat....................................................... 3
ToInstallThermostat................................................................ 4
WiringDiagrams.................................................................... 5
Heat/CoolSystems ................................................................ 5
Single Compressor heat pump with electric backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
DualCompressorheatpumpwithelectricbackup......................................... 6
RemoteSensorInstallation(Optional)................................................... 7
Terminal Designator Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
SC4811 Output Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
ConfigurationMode ................................................................. 9
ConfigurationModeSettings......................................................... 10
ModeofOperation................................................................. 15
ButtonFunctions.................................................................. 16
OperatingModes.................................................................. 17
TestingtheThermostat............................................................. 18
LockoutFeature................................................................... 19
SimpleSetTM FieldProgramming....................................................... 20
Troubleshooting................................................................... 21

1
Parts Diagram
Configuration switch
Reset switch
Left (system)
button
Right (fan)
button
Down button
Up button
Field programming pins
S1 S2 R C W
O/B GY1 W2 Y2
RESET CONFIG
FP

2
Specications
Icon Descriptions
Fan operation icon
Cooling operation icon
Heating operation icon
Lock mode
activated
Room
temperature
offset activated
Electrical rating: • 24 VAC (18-30 VAC)
• 1 amp maximum per terminal
• 3 amp maximum total load
Temperature control range: 45°F to 90°F (7°C to 32°C) Accuracy: ± 1°F (± 0.5°C)
System configurations: 2-stage heat, 2-stage cool, heat pump, gas, oil, electric
Timing: Anti-short Cycle: 4 minutes (bypass anti-short cycle delay by returning to OFF
mode for 5 seconds)
Backlight Operation: 10 seconds
Terminations: S1, S2, R, C, W/O/B, Y1, W2, Y2, G

3
Package Contents/Tools Required
Package includes: SC4811 thermostat on base, thermostat cover, wiring labels, screws and wall
anchors, Installation, Operation and Application Guide
Tools required for installation: Drill with 3/16” bit, hammer, screwdriver
Important Safety Information
WARNING! : Always turn off power at the main power supply before installing, cleaning, or
removing thermostat.
• This thermostat is for 24 VAC applications only; do not use on voltages over 30 VAC
• Do not short across terminals of gas valve or system control to test operation; this will damage your
thermostat and void your warranty
• All wiring must conform to local and national electrical and building codes
• Do not use air conditioning when the outdoor temperature is below 50 degrees; this can damage your
A/C system and cause personal injuries
• Use this thermostat only as described in this manual
To Remove Existing Thermostat
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.
1. Turn off power to the heating and cooling system by removing the fuse or switching the appropriate
circuit breaker off.
2. Remove cover of old thermostat. This should expose the wires.
3. Label the existing wires with the enclosed wire labels before removing wires.
4. After labeling wires, remove wires from wire terminals.
5. Remove existing thermostat base from wall.
6. Refer to the following section for instructions on how to install this thermostat.

4
To Install Thermostat
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 and cooling system by removing the fuse or switching the
appropriate circuit breaker off.
2. To remove cover, pull gently at the seam at the top.
3. 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).
4. Mark the placement of the mounting holes.
5. Set thermostat base and cover away from working area.
6. Using a 3/16” drill bit, drill holes in the places you have marked for mounting.
7. Use a hammer to tap supplied anchors in mounting holes.
8. Align thermostat base with mounting holes and feed the control wires through slit in thermal
intrusion barrier and into wire opening.
9. Use supplied screws to mount thermostat base to wall.
10. Insert stripped, labeled wires in matching wire terminals.
CAUTION!: Be sure exposed portion of wires does not touch other wires.
11. Gently tug wire to be sure of proper connection. Double check that each wire is connected to the
proper terminal.
12. Turn on power to the system at the main service panel.
13. Configure thermostat (see Page 11) to match the type of system you have.
14. Replace cover on thermostat by snapping it in place.
15. Test thermostat operation as described in “Testing the Thermostat” (Page 18).

5
Wiring Diagrams
120
VAC 24 VAC
Heat #1
Cool #1
Heat #2
Cool #2
Fan
Transformer
Heat/Cool Systems
Optional
remote or
outdoor sensor
* outdoor sensor only reads outdoor temperature

6
120
VAC 24 VAC
Reversing Valve
Compressor
Auxiliary Heat #1
Fan
Single Compressor
heat pump with electric backup
Dual Compressor
heat pump with electric backup
120
VAC 24 VAC
Reversing Valve
Compressor #1
Auxiliary Heat
Compressor #2
Fan
Transformer
Optional
remote or
outdoor sensor
Transformer
Optional
remote or
outdoor sensor
* outdoor sensor only reads outdoor temperature

7
Remote Sensor Installation (Optional)
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 strand shielded wire 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. Configure the thermostat to operate with the remote indoor sensor (see Configuration Mode setting 13,
Page 13) or use it for an outdoor sensor.
Note: Remote or outdoor sensor reading can be displayed by
simultaneously pressing the Down and SYS buttons.
Remote Sensor: (Shown: Optional ICM ACC-RT103 Remote Indoor Sensor;
for outdoor sensor, order ACC-OD103.)

8
R – 24 VAC hot
C – 24 VAC common
W1/O/B – Configurable
W1 – 1st stage heat for non-heat pump systems
O – cool active reversing valve
B – heat active reversing valve
Y1 – 1st stage cool, 1st stage heat for heat pumps
W2 – 2nd stage heat for non-heat pump systems
Y2 – 2nd stage cool for 2 compressor systems, 2nd stage heat for 2 compressor heat pump systems
G – Fan
Terminal Designator Descriptions
1ST Cool 2ND Cool 1ST Heat 2ND Heat
Heat/Cool Y1,G YI,Y2,G W1,G* W1,W2,G*
Heat Pump (One Compressor) Y1,G,O Y1,G,O Y1,G,B Y1,W2,G,B
Heat Pump (Two Compressors) Y1,G,O Y1,Y2,G,O Y1,G,B Y1,Y2,G,B
Emergency Heat (Heat Pump Only) N/A N/A W2,G W2,G
* G not energized when configured as a gas/oil system
The SC4811 thermostat is configurable for all systems. The configuration directly affects the outputs.
Use the output chart to correctly configure and wire the thermostat to your system.
SC4811 Output Chart

9
1ST Cool 2ND Cool 1ST Heat 2ND Heat
Heat/Cool Y1,G YI,Y2,G W1,G* W1,W2,G*
Heat Pump (One Compressor) Y1,G,O Y1,G,O Y1,G,B Y1,W2,G,B
Heat Pump (Two Compressors) Y1,G,O Y1,Y2,G,O Y1,G,B Y1,Y2,G,B
Emergency Heat (Heat Pump Only) N/A N/A W2,G W2,G
* G not energized when configured as a gas/oil system
OFF
1. Verify the SC4811 is in the OFF mode.
Press the SYS (left) button until off mode displays.
2. Remove the cover of the thermostat by gently pulling near one of the
corners at the top of the thermostat.
Press the up or down button to change settings within each screen.
S1 S2 R C W
O/B GY1 W2 W3Y2
RESET CONFIG
FP
Down
button
Up
button
Conguration Mode
3. Press the CONFIG button for 1 second while the SC4811 is in OFF mode.
To exit configuration mode, press the CONFIG switch for 1 second.
Press the right button to advance to the next screen.
Note: Pressing the left button will return you to the previous screen. Left
button
Right
button
The configuration mode is used to set the SC4811 to match your heating/cooling system. The SC4811
functions with heat pump, air conditioning, gas, oil or electric heat systems.
To configure the SC4811, perform the following steps:
CONFIG

10
Conguration Mode Settings
4. Staged Off Outputs
Select whether the outputs for heating and cooling are staged off independently
or are satisfied simultaneously.
1 = outputs staged off independently
0 = outputs off simultaneously
Press the up or down button to set.
Press the right button to advance to the next screen.
3. 2nd Stage Temperature Differential (1°F to 5°F) (0.5°C to 2.5°C)
Set the number of degrees between when stage 1 turns on and when
stage 2 turns on.
Press the up or down button to set differential value.
Press the right button to advance to the next screen.
2. 1st Stage Temperature Differential (1°F to 5°F) (0.5°C to 2.5°C)
Set the number of degrees between your “setpoint” temperature and your
“turn on” temperature.
Press the up or down button to set differential value.
Press the right button to advance to the next screen.
1. Temperature Scale (F or C)
Choose Fahrenheit or Celsius.
Press the up or down button to select.
Press the right button to advance to the next screen.
The setup screens for Configuration Mode are as follows:

11
5. Minimum Deadband (1°F to 9°F) (1°C to 5°C)
Set the minimum separation between heat setpoint and cool setpoint in
Auto Changeover Mode.
Press the up or down button to set deadband value.
Press the right button to advance to the next screen.
6. System – Set for heat pump, non-heat pump, reversing valve operation and number of compressors
in your system.
Press the up or down button to select.
Press the right button to advance to the next screen.
Choose System
Reversing
Valve Active
Number of Compressors
or Compressor Stages
Type of
Heat
Heat Pump
HP O 1
HP b 1
HP O 2
HP b 2
Non-Heat
Pump
Heat Gas
Heat Electric

12
7. Auxiliary Delay ON – (0-30 minutes)
Set the delay time in minutes for auxiliary heat to be locked out after a call
for second stage. This extra savings feature is used to temporarily lock out
auxiliary heat devices, allowing just heat pump to try to satisfy heat call.
Press the up or down button to select.
Press the right button to advance to the next screen.
8. Lockout (0-8°, COOL-HEAT)
Select the number of degrees set temperature can be changed during keypad
lockout. COOL-HEAT lockout allows adjustment of the set temperatures to
the maximum heat set temperature selected in Step 9 and minimum cool set
temperature selected in Step 10.
Note: The mode cannot be changed when the thermostat is locked.
Press the up or down button to select.
Press the right button to advance to the next screen.
9. Maximum Heat Setpoint (45°F to 90°F) (7°C to 32°C)
Adjust to control the maximum heat set temperature allowed.
Press the up or down button to select.
Press the right button to advance to the next screen.
10. Minimum Cool Setpoint (45°F to 90°F) (7°C to 32°C)
Adjust to control the minimum cool set temperature allowed.
Press the up or down button to select.
Press the right button to advance to the next screen.

13
13. Temperature Sensor (1-3)
1. Only on-board sensor determines room temperature.
2. Only remote sensor determines room temperature.
3. Average temperature of on-board and remote sensor.
Note: If there is no remote sensor, option 1 must be selected.
Press the up or down button to select.
Press the right button to advance to the next screen.
12. Maximum Cycles Allowed Per Hour (- -, 2-6)
- - = as many as needed, 2-6 = maximum cycles/hour
Press the up or down button to select.
Press the right button to advance to the next screen.
11. Room Temperature Offset (+9°F to -9°F) (+4.5°C to -4.5°C)
Adjust to calibrate displayed room temperature to match actual room
temperature.
Note: When not set to 0, will display
Press the up or down button to select.
Press the right button to advance to the next screen.
14. Cooling Fan Delay Off Time (0, 30, 60, 90 seconds)
Select the fan purge time for cooling.
Press the up or down button to select.
Press the right button to advance to the next screen.

14
15. Status Indicator Light (Led 0, 1, 2)
0 = Status indicator never on
1 = Status indicator on with first stage
2 = Status indicator on with second stage
Press the up or down button to select.
Press the CONFIG button for 2 seconds to exit configuration.

15
Mode of Operation
The SC4811 is an auto changeover, 2-stage heat, 2-stage cool thermostat. It functions with air
conditioning, heat pumps, gas, oil or electric heat systems. An outdoor sensor can be used to monitor
the outdoor temperature.
The thermostat activates the heating appliance when the room temperature is below the set heat
temperature (by the differential temperature) and the red indicator light (configurable) on the
thermostat will light. The SC4811 will stop outputting and the red light will turn off when the call for
heat has been satisfied. With heat pumps, the thermostat will not let the compressor come on for 4
minutes after it turns off. This protects your compressor.
When the room temperature is greater than the set cool temperature (by the differential temperature),
the cooling device is activated and the green indicator light (configurable) on the thermostat will turn
on. The SC4811 will stop outputting and the green light will turn off when the call for cooling is satisfied.
The thermostat will not let the compressor come on for 4 minutes after it turns off. This protects your
compressor.
The SC4811 has four possible operating modes: OFF, Heat, Cool, and Heat & Cool mode. In off mode,
the thermostat will not turn on heating or cooling devices. The manual fan can be turned on in all
operating modes using the fan button. In heat mode, the thermostat controls the heating system.
In the cool mode, the thermostat controls the cooling system. In heat & cool mode, the thermostat
controls both the heating and cooling systems. The clock display alternates with the set temperature
display for heat & cool mode.
The SC4811 also has a button lockout feature. This enables the thermostat to be set to the proper
mode and temperature and locked so it cannot be tampered with.

16
Button Functions
UP
Used to increase the time, set temperatures and to adjust configuration settings.
DOWN
Used to decrease the time, set temperatures and to adjust configuration settings.
SYS (left)
Used to change from OFF, HEAT, COOL and AUTO changeover modes
FAN (right)
Used to turn on and off the indoor fan.
UP, SYS and FAN
Held in simultaneously for 10 seconds to lock and unlock the thermostat.
DOWN and SYS
Pressed simultaneously to display outdoor temperature if outdoor remote sensor is connected.
SYStem (left) FAN (right)
Down button
Up button

17
Operating Modes
There are four possible operating modes for the SC4811. Off, Cool, Heat, and Cool & Heat modes are
accessed by pressing the SYS (left) button.
OFF Mode
• In this mode, the thermostat will not turn on the heating or cooling
devices
Note: The indoor fan can be turned on manually in every operating
mode by pressing the FAN (right) button. The word FAN
shows on the display and the fan icon appears when the
fan operates. OFF
Heat Mode
• In this mode, the thermostat controls the heating system. When the
heat outputs, the flame icon apprears on the display.
Note: For heat pumps, there is a four minute delay for your
compressor to restart after it has turned off. To bypass the
compressor time delay, go to OFF mode for 5 seconds.
Emergency Heat Mode (Heat pump systems only)
• In emergency heat mode, the heat pump system will be disabled and
auxiliary heat will become the primary source of heat.

18
Testing the Thermostat
Once the thermostat is configured, it should be thoroughly tested.
CAUTION! : Do not energize the air conditioning system when the outdoor temperature is
below 50 degrees. It can result in equipment damage or personal injury.
Heat Test
1. Press SYS (left) button until heat mode is displayed.
2. Adjust the set temperature so it is 5 degrees above the room temperature.
3. Heat should come on within a few seconds. Red LED may turn on.
4. Adjust the set temperature 2 degrees below the room temperature and the
heat should turn off. There may be a fan delay on your system.
Note: For heat pumps, there is a four-minute delay to protect your compressor after it turns off.
To bypass the compressor time delay, go to OFF mode for 5 seconds.
Cool Mode
• In this mode, the thermostat controls the cooling system. When the
cooling outputs, the snowflake icon apprears on the display.
Note: There is a four minute delay for your compressor to restart
after it has turned off. To bypass the compressor time delay,
go to OFF mode for 5 seconds.
Cool and Heat Mode (Auto Changeover)
• In this mode, the thermostat controls the cooling and heating systems,
automatically changing over from one to the other as needed.
• The timing display alternates with the set temperature every 10
seconds in the cool and heat mode.