I accidentally burned the 80-ohm resistor on my Salus 091FLRFv2 receiver. After replacing it, the receiver powers on but won't connect to the thermostat, and the code 'UEr' appears on the screen even after resetting and changing batteries. What does this mean?

The "UEr" code on a Salus 091FLRFv2 typically indicates a Software Version display (User Edition/Version) or a Communication Error between the thermostat and the receiver. Since you have performed a hardware repair on the receiver (replacing a resistor), the pairing between the two units may have been lost or the receiver's communication module may have been damaged during the initial short-circuit.Please try the following steps to restore the connection:Re-pair the devices: Although they are factory-paired, you may need to manually re-establish the link. On the 091FLRFv2, you can change the communication code without disassembling the unit. Refer to the "Changing Communication Code" section in your manual to ensure both the thermostat and receiver are on the same frequency channel.Check the Reset: Ensure you are using the reset button correctly. After pressing reset, the thermostat should return to its default settings. If "UEr" persists and the screen does not transition to the temperature display, the internal logic board may be damaged.Verify Receiver Status: Since the 80-ohm resistor was burned, other surface-mount components or the radio frequency (RF) module on the receiver board may have also sustained heat damage that isn't visible. If the receiver powers on (LEDs light up) but does not respond to the thermostat's test signal, the receiver likely needs replacement.Battery Check: Ensure you are using fresh AA Alkaline batteries. Rechargeable batteries often provide lower voltage (1.2V vs 1.5V) which can cause communication failures or stuck error codes.If the "UEr" code remains stuck and the unit does not respond to any button presses, it indicates a permanent electronic failure of the thermostat's processor.

Salus 091FLRFv2 Wireless Digital Thermostat Instruction Manual

1. Product Overview

The Salus 091FLRFv2 is a wireless digital thermostat designed for controlling heating and cooling systems. It features a weekly programming function, a clear LCD display, and a reliable 868 MHz radio frequency for communication between the thermostat unit and its receiver. This device is factory-paired for ease of installation.

Salus 091FLRFv2 Wireless Digital Thermostat and Receiver

Image 1.1: The Salus 091FLRFv2 Wireless Digital Thermostat (left) and its receiver (right).

2. Safety Information

Read all instructions carefully before installation and operation.
Installation should be performed by a qualified electrician or heating engineer.
Ensure the main power supply to the heating system is disconnected before installing or servicing the receiver unit.
Do not expose the thermostat or receiver to water or excessive humidity.
Keep out of reach of children.
Dispose of used batteries responsibly according to local regulations.

3. Components Included

The package contains the following items:

Salus 091FLRFv2 Wireless Digital Thermostat Unit
Salus 091FLRFv2 Receiver Unit
2 x AA Alkaline Batteries (for Thermostat)
Instruction Manual

4. Technical Specifications

Feature	Specification
Thermostat Power Supply	2 x AA Alkaline Batteries
Receiver Power Supply	230 V AC 50 Hz
Max Load	16 (5) A
Output Signal	Voltage-free Relay NO/COM
Temperature Setting Range	5 °C to 30 °C
Temperature Accuracy	0.2 °C
Hysteresis	± 0.25 °C or ± 0.5 °C
Radio Frequency	868 MHz
Wireless Range	Up to 60 m (open space)
Thermostat Dimensions (L x W x H)	154 x 80 x 30 mm
Receiver Dimensions (L x W x H)	96 x 96 x 27 mm
Display Type	LCD (Backlit)
Special Features	Weekly Program, Frost Protection

Image 4.1: Dimensions of the Salus 091FLRFv2 Thermostat unit.

5. Setup and Installation

5.1. Thermostat Unit Setup

Battery Installation: Open the battery compartment on the back of the thermostat. Insert the two supplied AA alkaline batteries, ensuring correct polarity. Close the compartment.
Placement: Place the thermostat in a central location within the heated area, away from direct sunlight, drafts, or heat sources. The integrated stand allows for desktop placement, or it can be wall-mounted.

5.2. Receiver Unit Installation

The receiver unit controls your heating/cooling system. It requires a 230V AC 50Hz power supply and should be wired by a qualified professional.

Power Disconnection: Before any wiring, ensure the main power supply to your heating/cooling system is completely disconnected.
Mounting: Mount the receiver unit in a suitable location near your heating/cooling appliance. It is designed for ceiling mounting or wall mounting.
Wiring: Connect the receiver to your heating/cooling system according to the wiring diagram provided in the full installation guide (not included here, refer to manufacturer's detailed manual). The output signal is a voltage-free relay (NO/COM).
Power Connection: Once wiring is complete and secure, restore the main power supply.

5.3. Factory Pairing

The thermostat and receiver units are factory-paired. No manual pairing is typically required for initial setup. If communication issues arise, refer to the troubleshooting section or the full manual for re-pairing instructions.

6. Operating Instructions

6.1. Basic Operation

Power On/Off: The thermostat powers on automatically once batteries are inserted. The receiver powers on when connected to mains electricity.
LCD Display: The backlit LCD displays current time, temperature, program status, and operating mode. The backlight duration is extended, returning to the main screen after up to 10 seconds of inactivity.
Temperature Adjustment: Use the '+' and '-' buttons (often indicated by sun/moon icons for day/night modes) to manually adjust the desired temperature.
Mode Selection: The thermostat supports both heating and cooling modes. Refer to the full manual for specific instructions on switching between modes.

6.2. Programming Weekly Schedule

The 091FLRFv2 offers 6 predefined programs and 3 user-definable programs. It features three temperature levels: Day, Night, and Anti-freeze.

Accessing Program Menu: Press the 'PROG' button (or similar, refer to device specific button layout) to enter the programming mode.
Setting Time and Day: Before setting programs, ensure the current time and day are correctly set. Use the appropriate buttons (e.g., 'SET', 'HOUR', 'MIN', 'DAY') to adjust.
Selecting Program: Navigate through the predefined programs or select a user-definable slot.
Defining Temperature Levels: For each time segment of the day, set the desired temperature level (Day, Night, or Anti-freeze).
Saving Programs: Follow the on-screen prompts to save your programmed schedule.

Image 6.1: Front view of the Salus 091FLRFv2 Thermostat, showing the LCD display and control buttons.

7. Maintenance

7.1. Battery Replacement

When the low battery indicator appears on the thermostat's display, replace the AA batteries promptly to ensure continuous operation. Use only alkaline batteries.

7.2. Cleaning

Clean the thermostat and receiver units with a soft, dry cloth. Do not use abrasive cleaners, solvents, or chemical sprays, as these can damage the plastic casing and electronic components.

8. Troubleshooting

No Display on Thermostat: Check if batteries are correctly inserted and not depleted. Replace if necessary.
No Communication with Receiver: Ensure the receiver is powered on. Verify that the thermostat and receiver are within the specified wireless range (up to 60m in open space). Obstacles like thick walls or metal objects can reduce range.
Heating/Cooling Not Activating: Check the receiver's power supply. Ensure the thermostat is set to the correct mode (heating/cooling) and the desired temperature is above/below the ambient temperature.
Changing Communication Code: The device allows changing the communication code without disassembling the units. Refer to the full manual for detailed instructions on this advanced feature if interference is suspected. The radio receiver supports up to 64,000 communication code combinations.

9. Warranty and Support

For warranty information, please refer to the documentation provided with your purchase or contact your retailer. For technical support or further assistance, please contact Salus customer service through their official website or the contact details provided in the product packaging.