3-heat / 2-cool non-programmable setback thermostat with economizer control with the industry’s most advanced remote sensor bus for gas, electric, & heat pump systems (6 pages)
This manual will describe how ® to install and test the Robertshaw RS10421T thermostat. This WiFi digital programmable thermostat allows you to control the temperature anytime and anywhere. It features a large backlit display and LCD touchscreen for ease of programming.
INSTALLATION MANUAL Important Safety Information Warning • Always turn off the power at the main power source by unscrewing fuse or switching circuit breaker to the off position before installing, removing, cleaning or servicing thermostat. • Read all of the information in this manual before installing or programming this thermostat.
INSTALLATION SPECIFICATIONS Display Range 32°F to 99°F (0°C to 40°C) Control Range 41°F to 90°F (5°C to 32°C) 1 amp per Terminal, 1.5 amp Maximum Load Rating all Terminals Combined HeatingisAdjustablefrom0.2° to 2.0° Differential CoolingisAdjustablefrom0.2°to 2.0° Power Source 18 to 30 VAC, NEC Class II, 50/60 Hz for Hardwire Operating Ambient 32°F to +105°F (0°C to +41°C) Temperature...
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INSTALLATION Back Plate Installation Caution: Electrical Hazard Disconnect power before installing this product. Failure to do so can cause electric shock or equipment damage. Mercury Notice This product is mercury-free. However, if this product is replacing a control which contains mercury, it needs to be disposed of properly.
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INSTALLATION Mounting Thermostat Align the 4 tabs on the faceplate with the corresponding slots on the back of the thermostat, then push gently until the thermostat snaps in place...
THERMOSTAT QUICK REFERENCE Getting to know your thermostat (RS10421T) (RS10421T) 1 Fan Buttons 2 Next Step Buttons 3 Set Time Buttons 4 Program Buttons 5 Menu Buttons 6 System Buttons 7 Setpoint Buttons...
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THERMOSTAT QUICK REFERENCE Getting to know your thermostat (RS10421T) (RS10421T) 1 Days of the week and time. 2 Indicates the current room temperature. 3 Displays the user selected setpoint temperature. 4 Hold is displayed when thermostat program is overridden. 5 System Operation Indicators:...
WIRING Caution: Electrical Hazard Disconnect power before installing this product. Failure to do so can cause electric shock or equipment damage. Wiring 1. If you are replacing a thermostat, make note of the terminal connections on the thermostat that is being replaced. In some cases the wiring connections will not be color coded.
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WIRING Terminal Designations The following terminals on the thermostat back plate are wired according to thetypeofHVACsystemconnectedtoandhowthethermostatisconfigured. 2 Heat 2 Cool 2 Heat 1 Cool Heat 3 Heat 2 Cool Heat Terminal Conventional Pump System Pump System System Transformer Power Transformer Power Transformer Power (cooling/heating) (cooling/heating)
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WIRING Installation Note: Devicessuchasafloatswitchthatmechanicallybreakcircuitsshould be installed so that they break the control wire (Y) not the power (R). Interrupting the power circuit will shut off power to the thermostat completely and not allow it to operate. Wire Specifications Tip Use 18- to 22-gauge thermostat wire. Shielded wire is not required.
WIRING DIAGRAMS Power supply Humidifierconnectionport UMIDIFIER connec on port Thermostat must be set to O and B to match the changeover valve. O is the cool changeover valve. B is the heat changeover valve. UMIDIFIER connec on port The Auxiliary Heat Relay is energized as the second stage of heat. DEHUMIDIFIER connec on port Dehumidifierconnectionport DEHUMIDIFIER connec on port...
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WIRING DIAGRAMS Note In many heat pump systems without an emergency heat relay, a jumper can be installed between E and W2 to turn the thermostat into a single stage control for Emergency Heat Operation. Typical Heat Only System with Fan Typical 2H/1C Heat Pump System...
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WIRING DIAGRAMS Typical 3H/2C with 24 VAC Humidifier Typical 2H/2C System with Dehumidify Terminal...
TECHNICIAN SETUP 1. Press MENU button. 2. Press and hold TECHNICIAN SETUP for 3 seconds. The 3 second delay is designed so that homeowners do not accidentally access the installer settings. 3.Configurethe installer options as desired using the table below. 4.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default The minimum compressor runtime can be adjusted from The installer can select the OFF to 3, 4 or 5 minutes. If 3, 4 Minimum minimum runtime for the or 5 is selected, the compressor Compressor compressor to help protect the will run for at least the selected...
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default The heating swing is factory preset at 0.4°. This means that whenever the room temperature cools by 0.4° full degree from Heating The heating swing setting is the temperature setting, the Swing adjustable from 0.2°F to 2°F.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default Thethermostatcanbeconfigured to operate up to a 2H/2C Use the keytofirst conventional heat pump system select stages of heat, press next - Stages of Heat or a 4H/2C conventional heat then select stages of cool.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default Thethermostatcanbeconfigured Program to have a 7 day program or be select 7d or 7 day, or Od for Options non-programmable. non-programmable. Heating Use the key to This feature allows you to set a Temperature select the maximum heat maximum heat setpoint value.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default 12- or 12-Hour Select a 12- or 24-hour clock Use the key to 24-Hour setting. Clock select 12- or 24-hour clock. Clock Select GAS or ELECT depending Operation on the type of furnace. Elec This setting will start heating Morning...
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default Thissettingwillconfigurethe fan to run a selected number of cycles per hour. Note: This mode can be enabled or disabled at any time during normal operation by selecting IAQ mode with the fan key.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default If ON is selected, the noise will An audible noise will sound sound. Beep when any key is depressed unless If OFF is selected there will be this setting is in OFF mode. no sound.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default Use the left and right arrows to Terminal See the chart below for HUM select the HUM terminal option. (Only shows if Terminal options See the chart below for an humidify is set explanation of these options.
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TECHNICIAN SETUP Tech Setup Steps LCD Will Show Adjustment Options Default Use the key to select Humidity OFF, 600, 1000, 1500 or 2000. Enables a reminder for the user to change the humidity pad. These represent hours of heat Reminder operation.
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TECHNICIAN SETUP Differential Setting Tip The second stage will turn on at 2x the differential setting and turn off at 1x the differential setting. For example, if the differential is 0.5°F for heatingandthethermostatissetat70°F,thefirststagewillturnonat approximately 69.5°F and turn off at approximately 70.5°F. The second stage will turn on at 69°F and turn off at approximately 69.5°F.
PROGRAMMING Set Time of Day and Day of Week 1. Press the MENU button. 2. Press SET TIME. 3. D ayoftheweekwillbeflashing.Use to select the current day of the week. 4. Press NEXT. 5. T hecurrenthourwillbeflashing.Use to select the current hour. Note the correct a.m.
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PROGRAMMING 1. Select HEAT or COOL. Note: Heat and cool need to be programmed separately. 2. Press MENU. 3. Press SET SCHED. Note: Monday will be displayed and the WAKE icon will be shown. 4. T imewillbeflashing.Use to make your time selection for that day’s WAKE time period.
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PROGRAMMING Factory Default Program Robertshaw RS10421T thermostats are shipped with an energy saving default ® program. The thermostat can be programmed to have all the weekdays the same, the same setpoints for all weekdays or a separate program for Saturday and a separate program for Sunday.
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PROGRAMMING Factory Default Program SETPOINT SETPOINT DAY OF THE EVENTS TIME TEMPERATURE TEMPERATURE WEEK (HEAT) (COOL) 6 a.m. 70°F (21°C) 75°F (24°C) Wake 8 a.m. 62°F (17°C) 83°F (28°C) Leave WEEKDAY 6 p.m. 70°F (21°C) 75°F (24°C) Return 10 p.m. 62°F (17°C) 78°F (26°C) Sleep ...
• Durable weatherproof design The RS9055OUT is an optional wireless outdoor remote • Compatible with RS9423T or temperature sensor and can be RS10421T thermostat used for dual fuel balance point • Wireless range from sensor to applications. thermostat is 328 feet (100m)
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9055OUT OPTIONAL ACCESSORY - RS9055OUT 9055OUT Subbase dismantling Mounting & Battery Installation Subbase dismantling To install the thermostat detach the rear panel of the thermostat from the Detach the rear panel of the To install the thermostat detach the front panel by loosening the screws remote from the front panel rear panel of the thermostat from the by loosening the screws at the...
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9055OUT OPTIONAL ACCESSORY - RS9055OUT 9055OUT Mounting & Battery Installation Install thermostat Installed in the same environment as the compressor 1. Position the rear panel with the 1.Position the top we insert at the top to wards the bottom of the remote and then snap toward the bottom.
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OPTIONAL ACCESSORY - RS9055OUT Getting to Know Your Remote Temperature Sensor The temperature of RS9055OUT is displayed in the upper left corner of RS10421T (OUTDOOR shows alternately with time). When HEAT PUMP is selected to ON (when the oil and gas dual-purpose system is enabled) and the RS9055OUT induction temperature is greater than the DUAL FUEL setting temperature, electric heating will be utilized.
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OPTIONAL ACCESSORY - RS9055OUT Radio Frequency Pairing 1. Press MENU button on RS10421T thermostat. 2. Press and hold TECHNICIAN SETUP button for 3 seconds. 3. Press FAN button to start RF PAIR (enter the learning code pairing mode). 4. Press and hold CONNECT button on RS9055OUT remote temperature sensor(redlightflashing) 5.
SETTING UP WIFI CONNECTION AND APP The Robertshaw RS10421T Programmable WiFi thermostat works with the Robertshaw Thermostat App which is available for iOS and Android platforms. Users can download the App from the Apple Store or Google Play. Use Phone to Scan for App...
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COMPLIANCE English “ This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject to the following two conditions: (1) this device may not cause interference, and (2) this device must accept any interference, including interference that may cause undesired operation of the device.” French “...
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FCC STATEMENT This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) This device must accept any interference received, including interference that may cause undesired operation.