Robertshaw RS8110 Operation Manual
Table of Contents
Thermostat Operation
The thermostat features an LCD display, a fan switch, a system switch, temperature set-point buttons, and an easy-change battery door.
1. LCD Display: Shows current room temperature, set-point temperature, and system status indicators.
2. Fan Switch: Select ON for continuous fan operation or AUTO for fan operation only during heating or cooling cycles.
3. System Switch: Select HEAT for heating mode, COOL for cooling mode, or OFF to disable both heating and cooling.
4. Temperature Set-Point Buttons: Use the up (▲) and down (▼) buttons to adjust the desired temperature.
5. Easy change battery door: Provides access to the battery compartment.
Caution
Do not switch the system to cool if the temperature is below 50°F (10°C). This can damage the air conditioning system and cause personal injury.
Thermostat Quick Reference
Battery Door Information
To open the easy access battery door, press the lower portion of the thermostat.
Illustration showing the lower part of the thermostat being pressed to open the battery door.
Install two AAA Alkaline batteries into the battery compartment. Ensure that the positive (+) ends of the batteries match the positive (+) battery terminals in the compartment.
Illustration showing two AAA batteries being inserted into a battery compartment, with positive terminals aligned.
Caution
When the low battery icon appears, replace the 2x AAA batteries immediately. Failure to do so may result in your heating and cooling system becoming inoperable. Freezing or overheating can occur.
LCD Screen Indicators
Room Temperature: Indicates the current room temperature.
Set-Point Temperature: Displays the user-selected set-point temperature.
Illustration of the thermostat's LCD screen displaying "Room 72°F" and "Set At 72°F".
System Operation Indicators: The snowflake (❄️), flame (?), or fan (?️) icon will display when the COOL, HEAT, or FAN is on, respectively.
NOTE: If these icons are flashing, there is a 5-minute delay for compressor protection.
Low Battery Indicator: Replace batteries when this indicator is shown.
Adjusting the Temperature Differential
Cooling Differential or Swing
The cooling differential is factory preset at 0.5°F. This means the cooling system turns on when the room temperature rises 0.5°F above the set-point. To increase the cooling differential (reduce cycling frequency), select COOL and hold down the up (▲) and down (▼) buttons together for 3 seconds. Use the up (▲) and down (▼) buttons to adjust the cooling differential between 0.2°F and 2°F. Wait approximately 15 seconds or toggle the system switch to return to normal operation.
Heating Differential or Swing
The heating differential is factory preset at 0.4°F. This means the heating system turns on when the room temperature drops 0.4°F below the set-point. To increase the heating differential (reduce cycling frequency), select HEAT and hold down the up (▲) and down (▼) buttons together for 3 seconds. Use the up (▲) and down (▼) buttons to adjust the heating differential between 0.2°F and 2°F. Wait approximately 15 seconds or toggle the system switch to return to normal operation.
Calibration Setting
To access the CALIBRATION setting and adjust the temperature, select OFF and hold down the up (▲) and down (▼) buttons together for 3 seconds. Use the up (▲) and down (▼) buttons to adjust the temperature from between -4°F and +4°F.
Press the down (▼) button to select Fahrenheit (°F) or Celsius (°C), and press the up (▲) button to select the temperature scale.
Then, press the down (▼) button to access the compressor short cycle DELAY setting. If the compressor short cycle delay setting is ON, the compressor cannot be turned on for at least 3 minutes after it was last turned off. Use the up (▲) and down (▼) buttons to adjust the compressor short cycle delay setting to ON or OFF. Wait approximately 15 seconds or toggle the system switch to return to normal operation.
Terminal Designations
- RH: 24 VAC (system power supply) HEAT
- RC: 24 VAC (system power supply) COOL
- C: Common 24 VAC (system power supply)
- W: HEAT
- Y: COOL
- G: FAN
- B: REV VALVE HEAT
- O: REV VALVE COOL
