Robertshaw RS10420T Installation Manual

Introduction

The Robertshaw® Programmable WiFi Thermostat allows you to control the temperature anytime and anywhere. It features a large backlit display and LCD touchscreen for ease of operation. Compatible with any IOS or Android Smartphone.

Thermostat System Types

Gas, Oil, or Electric Heat with Air Conditioning
Heat Pumps (without auxiliary or emergency heat)
Multi-Stage Systems
Heat-Only, including for Floor and Wall-Furnace
Cool-Only
750 Millivolt Heating Systems

Power Options

Hardwire (Common Wire) only

Important Safety Information

WARNING:

Always turn off 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.
This is a 24V AC low voltage thermostat. Do not install on voltages higher than 30V AC.
All wiring must conform to local and national building and electrical codes and ordinances.
Do not short (jumper) across terminals on the gas valve or at the system control to test installation. This will damage the thermostat and void the warranty.

Specifications

Parameter	Value
Temperature Display Range	32°F to 99°F (0°C to 40°C)
Temperature Control Range	41°F to 90°F (5°C to 32°C)
Load Rating	1 amp per terminal, 1.5 amp maximum all terminals combined
Differential	Heating is adjustable from 0.2° to 2.0° Cooling is adjustable from 0.2° to 2.0°
Power Source	18 to 30 VAC, NEC Class II, 50/60 Hz for hardwire
Operating Ambient Temperature	32°F to +105°F (0°C to +41°C)
Operating Humidity	90% non-condensing maximum
Dimensions	4.7"W x 4.4"H x 1"D

Installation Location

Wallplate Installation

1 Horizontal Mount

2 Vertical Mount

For a vertical mount, put screws on the top and bottom.

For a horizontal mount, put screws on the left and the right.

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. Contact your local waste management authority for instructions regarding recycling and proper disposal of the control.

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 into place.

Install the thermostat 4 to 5 feet above the floor in an area with good air circulation and average temperature.

For new installations, mount thermostat on an inside wall, 4-5 feet above the floor. Do not install the thermostat in the following locations:

Behind a Door
In a Corner
Near Air Vents
In Direct Sunlight
With an Outside Wall Behind the Thermostat
Near any Heat or Steam Generating Fixtures
Near any Concealed Pipes or Chimneys

Installation at these locations will affect thermostat operation.

Diagram shows the thermostat display with current time (Sun, 8:00 AM), current temperature (72°F), set temperature (78°F), and system mode (Heat). Buttons are labeled FAN, AUTO, ON, IAQ, TECHNICIAN SETUP, NEXT STEP, SET TIME, CLEAN, NEXT ZONE, SET SCHEDULE, HOLD, PREVIOUS STEP, SYSTEM, MENU, DONE.

Thermostat Quick Reference

Getting to know your thermostat

Diagrams show the thermostat interface and display indicators. The left diagram shows buttons labeled 1-7 and their functions: 1 Fan Buttons, 2 Next Step Buttons, 3 Set Time Buttons, 4 Program Buttons, 5 Menu Buttons, 6 System Buttons, 7 Set-Point Buttons. The right diagram shows the display with time, day of week, temperature, set-point, and system indicators. It also lists: 1 Days of the week and time, 2 Current room temperature, 3 User selected set-point temperature, 4 Hold indicator, 5 System Operation Indicators (5-minute delay for compressor protection), 6 Programmable Time Periods (WAKE, RETURN, LEAVE, SLEEP), 7 Program Menu Options.

1 Fan Buttons
2 Next Step Buttons
3 Set Time Buttons
4 Program Buttons
5 Menu Buttons
6 System Buttons
7 Set-Point Buttons

Display Indicators and Features:

1 Days of the week and time
2 Indicates the current room temperature
3 Displays the user selected set-point temperature
4 Hold is displayed when thermostat program is overridden.
5 System Operation Indicators: If these icons are flashing, there is a 5-minute delay for compressor protection.
6 Programmable Time Periods: Residential uses 4 time periods - WAKE, RETURN, LEAVE and SLEEP.
7 Program Menu Options: Shows different options during programming.

Wiring

Terminal Designations

	Y1	Y2	W/E	W2	0	B
CONVENTIONAL HVAC	COOL MODE STAGE 1	COOL MODE STAGE 2	HEAT MODE STAGE 1	HEAT MODE STAGE 2	-	-
HEAT PUMP	1H / 1C	HEAT 1 COOL 1	HEAT 2 COOL 2	AUX 1 HEAT 2 AUX 1	HEAT 2 AUX 2 HEAT 3 AUX 2	HEAT PUMP REVERSING VALVE - ENERGIZED DURING COOLING	HEAT PUMP REVERSING VALVE - ENERGIZED DURING HEATING
	2H / 1C		HEAT 2 COOL 2	AUX 1 HEAT 3 EMHEAT	AUX 2 HEAT 4 EMHEAT
	3H / 1C
	2H / 2C
	3H / 2C
	4H / 2C

Installation Tip

? Do not overtighten terminal block screws, as this can damage the terminal block. A damaged terminal block can keep the thermostat from fitting on the subbase correctly or cause system operation issues. Max Torque = 6in/lbs.

Notes

Wire Specifications

Use 18- to 22-gauge thermostat wire. Shielded wire is not required.

Emergency Heat Operation

In many heat pump systems with no emergency heat relay, a jumper can be installed between E and W2 to turn thermostat into a single stage control for Emergency Heat Operation.

Float Switches

A float switch or similar device which breaks the control wire (Y) not the power (R) should be installed. Interrupting the power circuit will shut off the power to the thermostat completely and stop it from operating.

Wiring Diagrams

Diagram Key

1 Power supply
2 Factory-installed jumper. Remove only when installing on 2-transformer systems
3 Use either O or B terminals for reversing valve
4 24 VAC common connection

Typical 2H/2C System: 1 Transformer

Wiring diagram for a 2H/2C system with 1 transformer. Shows connections from power supply (R, C) to terminals (RC, RH, Y, C, W/E, G, W2, Y2) on the thermostat. Relays for Compressor, Heat, Fan are depicted. Power supply L1 (HOT) and L2 are shown connected to R and C terminals via a switch.

Typical Cool-Only System With Fan

Wiring diagram for a Cool-Only system with fan. Shows connections from power supply (R, C) to terminals (RC, RH, Y, C, W/E, G) on the thermostat. Relays for Compressor and Fan are depicted. Power supply L1 (HOT) and L2 are shown connected to R and C terminals via a switch.

Typical Heat Only System With Fan

Wiring diagram for a Heat Only system with fan. Shows connections from power supply (R, C) to terminals (RC, RH, Y, C, W/E, G) on the thermostat. Relays for Heat and Fan are depicted. Power supply L1 (HOT) and L2 are shown connected to R and C terminals via a switch.

Note:

In many systems with no emergency heat relay, a jumper can be installed between E and W2.

Typical 3H/2C or 2H/1C Heat Pump System

Wiring diagram for a 3H/2C or 2H/1C Heat Pump system. Shows connections from power supply (R, C) to terminals (RC, RH, Y, C, W/E, G, W2, Y2) on the thermostat. Relays for Compressor, Emergency Heat, Fan, Auxiliary Heat, Compressor Relay 2, Cool Reversing Valve, and Heat Reversing Valve are depicted. Power supply L1 (HOT) and L2 are shown connected to R and C terminals via a switch.

Typical 2H/2C System: 2 Transformers

Wiring diagram for a 2H/2C system with 2 transformers. Shows connections from two separate power supplies (R, C) to thermostat terminals (RC, RH, Y, C, W/E, G, W2, Y2). Relays for Compressor, Fan, Heat, Compressor Relay 2, and Heat Relay 2 are depicted. A jumper is shown to be removed for this configuration.

Installer Setup

Steps to enter setup:

Press MENU.
Press and hold TECHNICIAN SETUP for 3 seconds.
Configure the installer options as desired using the table below.
Use + or - to change settings and the NEW STEP or PREV STEP to move from one step to another. Note: Only press DONE when you want to exit the Installer Setup options.

Settings Table

Settings	Display	Adjustment Options	Default
Setup WiFi	WIRELESS SETUP	WiFi router parameter configuration
Filter Change Reminder	FILTER OFF SE	The filter change reminder can be adjusted from OFF to 2000 hours in 50 hour increments. Press the second button from the top left side of the thermostat to display the current filter elapsed run time.	OFF
Room Temperature Calibration	CALIBRATE 0°F	The room temperature display can be adjusted to read 4° above or below the factory calibrated temperature.	0

Settings	Display	Adjustment Options	Default
Minimum Compressor On-Time	MIN COMP OF	The minimum compressor run time can be adjusted from OFF to 3, 4, or 5 minutes. If 3, 4, or 5 is selected, the compressor will run for at least the selected time before turning off (although the fan may continue to run for a short time).	OFF
Compressor Short Cycle Delay	COMP PROTECTS ON	The compressor short cycle delay setting can be removed by selecting OFF.	ON
Cooling Differential	COOL SWING 0.5°F	The cooling differential setting is adjustable from 0.2°F to 2°F.	0.5

Settings	Display	Adjustment Options	Default
Heating Differential	HEAT SWING 0.4°F	The heating differential setting is adjustable from 0.2°F to 2°F.	0.4
Heat Pump	HEAT PUMP OF	Use + or - to configure the setting. OFF for conventional systems and ON for heat pump systems.	OFF
System Switch	SYSTEM SET	The system switch can be configured for the particular application. Heat - Off - Cool, Heat - Off, Cool - Off, Heat - Off - Cool - Auto. Note: Emergency Heat is available in heat pump mode only.	OFF
Stages of Heat and Cool	2H2C STRGS OF HEAT+COOL	If the heat pump is still ON, this thermostat can be configured to operate up to 2H/2C conventional, or up to 4H/2C heat pump system. Use + or - to select stages of heat, press NEXT, then select stages of cool. 3 or 4 heat will use Y1 and Y2 as 1st and 2nd stage of heat.	2 STAGES

Settings	Display	Adjustment Options	Default
Cooling Fan Delay	COOL FAN DELAY OF	The cooling fan delay can be set to OFF, 15, 30, 60 or 90 seconds. If 15, 30, 60 or 90 is selected, the fan will not turn on for at least the selected time when there is a call for cool and will run for at least the selected time after satisfying the call for cool.	OFF
Heating Temperature Set-Point Limit	HEAT LIMIT 90°F	Use + or - to select the maximum heat temperature set-point. The maximum heat temperature set-point is 90°F. Range 44°F - 90°F	90°
Cooling Temperature Set-Point Limit	COOL LIMIT 44°F	Use + or - to select the maximum cool temperature set-point. The minimum cool temperature set-point is 44°F. Range 44°F - 90°F	44°
F° or C°	83°F (F OR C SET)	°F for Fahrenheit °C for Celsius	F°

Settings	Display	Adjustment Options	Default
12 or 24 Hour Clock	12H	Use + or - to select 12 or 24 hour clock.	12 Hour Clock
Fan Operation	GAS FAN OPERATION	Select GAS or ELEC depending on the type of furnace.	GAS
Morning Recovery	MORNING RECOVERY ON	This setting will start heating early to bring the building temperature to its programmed set-point by the beginning of the WAKE time period. Use + or - to turn ON or OFF.	ON
Display Light	AUTO DL	AUTO - Any key ON ON - Always ON	AUTO
Contractor Call Number	PHONE NUM OF	The thermostat allows installers to put their phone number in the display. If selected ON, the input screen will appear after pressing NEXT STEP. Use + or - key to select the desired telephone number and the FAN or SYSTEM key to change characters.	OFF

Settings	Display	Adjustment Options	Default
Beep	BEEP OF	If ON is selected, the beep will sound. If OFF is selected, the beep will be silenced.	ON
MACID	MACID 980863079022	This step shows the MAC address of WiFi module.
Firmware Version	FIRMWARE VER 0100	This step shows the version of firmware that is installed on the thermostat.
Factory Default Reset	NO DEFAULT	This step resets all WiFi settings to factory default. Press NEXT to move to next step. Press DONE to exit. Press and hold TECH to enter ADVANCED TECH STEPS. Press YES to reset.

Programming

Programming Notes

Differential Setting

The second stage will turn ON at 2x the differential setting and OFF at 1x the differential setting. For example, if the differential setting is 0.5° for heating and the thermostat is set at 70°F, the first stage will turn on at 69.5°F. The second stage will turn on at 69°F and turn off at 69.5°F. If the third stage is used, the third stage will turn on at 68.5°F and turn off at 69°F.

Keypad Lockout

The installer can activate a keypad lockout after exiting Tech Setup.

Auto Changeover

In Auto mode, users can toggle between Auto Heat or Auto Cool by pressing System only when the current mode has reached its temperature set point. To switch out of Auto mode, hold down System. To return to Auto mode, toggle the System key to Auto.

Reminders

Once a Reminder has been turned on and set, the elapsed time can be checked by navigating the Tech Setup step. The time can be reset by pressing and holding the third button from the left for 3 seconds. Resetting an expired Reminder can be done by pressing and holding the 3rd button from the left for 3 seconds.

Contractor Call Number

If contractor call number is selected ON, the selected phone number will show in the display if there has been a continuous call for heating or cooling for 24 hours or if the FAN button is held down for 3 seconds. To remove the phone number from the display, hold the FAN button down for 3 seconds.

Set Time of day and day of the week (If using programming)

Press the MENU button.
Press SET TIME.
Day of the week will be flashing. Use + or - to select the current day of the week.
Press NEXT.
The current hour will be flashing. Use + or - to select the current hour. Note the correct a.m. or p.m. indicator is selected.
Press NEXT.
The minutes will be flashing. Use + or - to select current minutes.
Press DONE when completed.

Setting Schedules

Select HEAT or COOL using the system key. Note: Heat and cool need to be programmed separately.
Press MENU (If menu does not appear first, press RUN SCHED).
Press SET SCHED. Note: Monday will be displayed and the WAKE icon ?☀️ is shown.
Time will be flashing. Use + or - to make your time selection for that day's WAKE time period. Note: If you want the fan to run continuously during this time period, select ON with the FAN key.
Press NEXT STEP.
The set-point temperature will be flashing. Use + or - to make your set-point selection for the WAKE time period for Monday–Friday (or Monday if in 7 Day mode).
Press NEXT STEP.
Repeat steps 4 through 7 for the LEAVE time period, for the RETURN time period, and for the SLEEP time period for Monday–Friday (or Monday if in 7 Day mode).
Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday: Repeat steps 4 thru 7 for the remaining days of the week.

Default Program

This thermostat is pre-programmed for energy saving operation. The default program is below:

Day of the Week	Events	Time	Set-Point Temperature (Heat)	Set-Point Temperature (Cool)
Weekday	Wake ?☀️	6 a.m.	70°F (21°C)	75°F (24°C)
	Leave ?	8 a.m.	62°F (17°C)	83°F (28°C)
	Return ?	6 p.m.	70°F (21°C)	75°F (24°C)
	Sleep ?	10 p.m.	62°F (17°C)	78°F (26°C)
Saturday	Wake ?☀️	8 a.m.	70°F (21°C)	75°F (24°C)
	Leave ?	10 a.m.	62°F (17°C)	83°F (28°C)
	Return ?	6 p.m.	70°F (21°C)	75°F (24°C)
	Sleep ?	11 p.m.	62°F (17°C)	78°F (26°C)
Sunday	Wake ?☀️	8 a.m.	70°F (21°C)	75°F (24°C)
	Leave ?	10 a.m.	62°F (17°C)	83°F (28°C)
	Return ?	6 p.m.	70°F (21°C)	75°F (24°C)
	Sleep ?	11 p.m.	62°F (17°C)	78°F (26°C)

Setting Up WiFi Connection and App

The Robertshaw RS10420T 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.

QR code for App Installation Instructions. Scan with phone for details.

Icon representing a house with sun and snowflakes, and Wi-Fi signal waves, indicating smart home climate control.

Contact and Warranty Information

Customer Service: +1.800.304.6563

Technical Service: +1.800.445.8299

Email: HVACCustomerService@robertshaw.com

Website: www.robertshaw.com

Document Reference: 352-00308-001 Rev. B

Robertshaw® is a trademark of Robertshaw Controls Company.

Warranty: 6 Year Limited Warranty

QR code for Warranty Information. Scan with phone for details.

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