Salus RT520 Series Smart Thermostat Quick Guide

Introduction

The Salus RT520 and RT520RF are advanced heating control thermostats offering optimum efficiency and comfort. They feature a new on-board load compensation feature, a larger LCD display, and additional operational functions. This guide covers setup, configuration, and key features.

Product Compliance

This product complies with EU Directives: EMC 2014/30/EU, LVD 2014/35/EU, RED 2014/53/EU, and RoHS 2011/65/EU. The full EU Declaration of Conformity is available at www.saluslegal.com.

Radio Frequency: 868.0-868.6MHz; <13dBm

Safety Information

Use this device in accordance with national and EU regulations. Ensure it is kept in a dry condition and used only indoors. Installation must be performed by a qualified person. Always switch off the AC mains power before installation or working on components. Use only AA 1.5 V alkaline batteries in the thermostat; do not use rechargeable batteries.

Technical Specifications

Button Functions

RT520 / RT520RF Thermostat Buttons

• 1. MENU: Enter menu options; press and hold for 3 sec to return to main screen or deactivate Boost Mode.
• 2. SELECT: Confirm changes and enter menus.
• 3. DOWN: Decrease temperature and move through menus.
• 4. UP: Increase temperature and move through menus.
• 5. BOOST: Activate Boost Mode.
• 6. MANUAL: Activate / deactivate Manual Mode.

RXRT520 Receiver Switches

• 7. ON: When in Manual Mode, turns the boiler ON.
• 8. OFF: When in Manual Mode, turns the boiler OFF.
• 9. AUTO: Receiver operates automatically according to the thermostat.
• 10. MANUAL: Receiver output controlled by the On/Off slide switch.

LCD Icon Description

The thermostat display features several icons:

• 1. Text Bar: Indicates current status.
• 2. Temperature Unit: Displays °C.
• 3A. Day of the week (numeric): e.g., 1 for Monday.
• 3B. Day of the week (alphabetic): e.g., MON for Monday.
• 4. Clock: Displays current time.
• 5. AM/PM: Indicates morning or afternoon.
• 6. Frost Protection Mode On: ❄️ Icon displayed when frost protection is active.
• 7. Holiday Mode On: ?️ Icon displayed when holiday mode is active.
• 8. Manual Mode On: ⚙️ Icon displayed when manual mode is active.
• 9. Heating Mode On: ? Icon displayed when the heating is active.
• 10. Low battery status: ? Icon displayed when batteries are low.
• 11. Wireless connection with the receiver: ? Icon displayed for wireless link status.
• 12. Service Mode On: ? Icon displayed when service mode is active.
• 13. Temperature measured / set: Displays current room temperature and setpoint.
• 14. Program number: Indicates the active program.
• 15. Settings: ⚙️ Icon for general settings.
• 16. Program indicator: Shows program status.
• 17. Boost function: ? Icon for boost mode.

RT520 Thermostat Terminals Description

RT520TX Thermostat Terminals Description

RXRT520 Receiver Terminals Description

Wiring Diagrams

RT520 Wiring Diagram

This diagram illustrates the wiring for the RT520 thermostat. It shows connections for TPI, SPAN, and OPENTHERM. The thermostat has terminals for COM, NO, NC, and B/A. The RXRT520 receiver has terminals for COM, NO, L, and N.

[Diagram Description: Shows RT520 thermostat connected to OPENTHERM and TPI/SPAN inputs. Also shows RXRT520 receiver with L, N, COM, and NO connections.]

RT520TX Wiring Diagram

This diagram illustrates the wiring for the RT520TX thermostat. It shows connections for TPI, SPAN, and OPENTHERM. The thermostat has terminals for COM, NO, NC, and B/A. The RXRT520 receiver has terminals for COM, NO, L, and N.

[Diagram Description: Shows RT520TX thermostat connected to OPENTHERM and TPI/SPAN inputs. Also shows RXRT520 receiver with L, N, COM, and NO connections.]

OpenTherm Power Up and Configuration

OpenTherm Modulating Control is an advanced method that allows the boiler's heat output to be precisely matched to the thermostat's demand, improving system efficiency, energy savings, and room comfort.

Before proceeding: Make the receiver connections and power the receiver before inserting batteries into the thermostat.

1. Step 1: Set Day

   Using the UP or DOWN buttons, set the current day, then press SELECT.

2. Step 2: Set Temperature Accuracy

   Using the UP or DOWN buttons, select your desired temperature accuracy, then press SELECT to confirm.

3. Step 3: Set Week Format

   Using the UP or DOWN buttons, select the week format (e.g., 5-day/2-day), then press SELECT to confirm.

4. Step 4: Language Selection

   Using the UP and DOWN buttons, choose your preferred language, then press SELECT.

5. Step 5: Set Time Format

   Using the UP or DOWN buttons, choose the time format (12-hour or 24-hour), then press SELECT to confirm.

6. Step 6: Set Hour

   Using the UP or DOWN buttons, set the current hour, then press SELECT.

7. Step 7: Set Minutes

   Using the UP or DOWN buttons, set the current minutes, then press SELECT.

8. Step 8: Set Year

   Using the UP or DOWN buttons, set the current year, then press SELECT.

9. Step 9: Set Month

   Using the UP or DOWN buttons, set the current month, then press SELECT.

After inserting batteries, the thermostat will power up. If OpenTherm is connected, the device software will automatically adjust to OpenTherm settings.

The thermostat will return to the main screen. Press any button to wake it up.

OpenTherm - Hot Water Configuration

This section details how to configure hot water settings using OpenTherm.

1. Press the MENU button.
2. Using the UP or DOWN buttons, navigate to the Hot Water submenu, then press SELECT.
3. Using the UP or DOWN buttons, adjust the desired hot water temperature, then press SELECT.

The text bar on the display indicates that hot water is currently in operation.

Standard Power Up and Configuration

Follow steps 1 to 14 from the "OpenTherm Power Up and Configuration" section for initial setup.

TPI (Time Proportional & Integral)

TPI is a self-learning algorithm that ensures economical system operation by maintaining accurate temperatures and limiting overload conditions. It offers significant energy savings. RT520 supports three TPI types:

• 1. For radiator (6CPH)
• 2. For underfloor heating (3CPH)
• 3. For electric heating (9CPH)

[Visual representation of TPI selection options: RAD (Radiator), UFH (Underfloor Heating), ELEC (Electric Heating). User selects one using UP/DOWN and confirms with SELECT.]

Span

Span is the difference between the measured temperature and the set temperature. Adjust the Span value using UP/DOWN buttons and confirm with SELECT.

[Visual representation of Span value selection, showing options like 1.5, 1.2, 2. User selects a value and presses SELECT.]

Optimum Start

Optimum Start is a selectable function that intelligently starts the boiler operation based on ambient room temperature to achieve the set-point temperature at the optimal time, saving energy.

[Visual representation of Optimum Start activation button on the thermostat interface. User presses SELECT to enable this feature.]

Optimum Stop

Optimum Stop calculates how long the house will take to cool down and turns off the boiler at the earliest possible moment to prevent unnecessary operation. If heat loss occurs, Optimum Stop is overridden to maintain comfort.

[Visual representation of Optimum Stop activation button on the thermostat interface. User presses SELECT to enable this feature.]

Programming - Automatic Mode

In Automatic Mode, users can set heating schedules for specific periods of time. Programmed schedules should utilize all available time periods.

1. Press SELECT.
2. Using UP or DOWN, select ON or OFF for the current period, then press SELECT.
3. Using UP or DOWN, set the desired hour, then press SELECT.
4. Using UP or DOWN, set the desired minutes, then press SELECT.
5. Using UP or DOWN, set the desired temperature, then press SELECT.

Repeat this process for all time periods. The thermostat offers flexible scheduling options:

• +2: Schedule for working days and weekends separately.
• All: One schedule for the entire week.
• Individual: Set a daily schedule.

[Visuals depict setting time (hour/minute) and temperature for heating periods. Options for '+2' (weekday/weekend), 'All' (full week), and 'Individual' (daily) schedules are shown.]

Landlord Settings

This is a PIN code protected feature allowing landlords to set a service reminder for the boiler's annual service. The thermostat will warn the tenant when service is due.

1. Press MENU.
2. Using UP or DOWN, navigate to the Landlord submenu, then press SELECT.
3. Using UP or DOWN, enter the 4-digit PIN code number, pressing SELECT to confirm each digit.
4. Using UP or DOWN, select ON or OFF for the service reminder, then press SELECT.
5. Using UP or DOWN, select the due date for the service, then press SELECT.

The thermostat will return to the main screen.

Note: Once service mode is active, the device locks the set point temperature. To unlock, the landlord must be contacted and the boiler serviced. Landlord settings are not reset during a factory reset.

RT520TX Thermostat Pairing with the Receiver

If you purchased the RT520RF pack, pairing is pre-done. For RT520TX and RXRT520 purchased separately, or for re-pairing:

Preparation: Disconnect power from the receiver. Set the receiver switches to AUTO and ON.

1. Connect the receiver to the power supply. Wait for the red LED to light steadily.
2. Quickly switch the receiver's switch from OFF to ON position. The red flashing LED indicates pairing mode.
3. Press MENU on the thermostat.
4. Using UP or DOWN, navigate to the Pairing submenu, then press SELECT.
5. Using UP or DOWN, select PAIR, then press SELECT.

The pairing process can take up to 10 minutes. Once successful, the receiver's red LED will turn solid red.

Test the Pairing Process

1. Press MENU on the thermostat.
2. Using UP or DOWN, navigate to the Pairing submenu, then press SELECT.
3. Using UP or DOWN, select TEST, then press SELECT.

The testing process takes up to 10 minutes. The red and green LEDs on the receiver will flash during testing.

[Visuals illustrate the thermostat interface during the pairing process (showing 'PAIRING' and 'TESTING' screens) and the receiver's LED status (flashing red/green).]

Factory Reset

To reset the thermostat to factory default settings:

1. Press and hold MENU, DOWN, and BOOST buttons simultaneously for 5 seconds.

The device will reset and start up automatically. Landlord settings will not be reset.

[Visual shows the thermostat display indicating the factory reset procedure (simultaneous button press).]