Heatmiser Slimline-RF Programmable Thermostat

Introduction

The Heatmiser Slimline-RF is a wireless programmable room thermostat designed to control your heating system efficiently. This manual provides comprehensive instructions for installation, setup, and operation.

The thermostat combines the functions of a programmer and a room thermostat, allowing you to set 'On' and 'Setback' periods to suit your lifestyle. It senses room temperature and switches heating on when the temperature drops below the set point and off when it is reached. This enables you to select different temperatures for different times of the day and week, meeting your specific needs and preferences.

Proper use of a programmable thermostat can lead to energy savings by maintaining lower temperatures when not needed.

Product Overview

The Slimline-RF is a wall-mounted wireless thermostat. It features a clear LCD display and intuitive button controls.

Model: Slimline-RF

Installation Procedure

This wireless thermostat is designed for surface mounting.

Do

• Mount the thermostat at eye level.
• Read the instructions fully to get the best from the product.

Don't

• Do not install near a direct heat source as this will affect functionality.
• Do not push hard on the LCD screen as this may cause irreparable damage.

Steps:

1. Carefully separate the front half of the thermostat from the back plate by placing a small flat head terminal driver into the slots on the bottom face of the thermostat.
2. Mark 2 hole positions on the wall using the backplate as a positioning template. Drill at the marked positions and insert a wall plug into each hole.
3. Screw the thermostat back plate securely on the wall.
4. Clip the front of the thermostat back onto the thermostat back plate.

Image Description: Four images illustrate the installation steps: 1. The thermostat unit. 2. The backplate mounted on a wall with wires. 3. Inserting batteries into the backplate. 4. Clipping the front unit onto the backplate.

Installing the Batteries

The thermostat requires 2x AAA batteries, which are supplied with the unit.

To access the battery holder, push and release the compartment door located on the bottom face of the thermostat. The thermostat will display a battery icon on screen when the batteries need replacing. Do NOT use rechargeable batteries with this product.

Image Description: Two AAA alkaline batteries are shown next to the thermostat, with the battery compartment pulled out from the bottom.

Diagram Description: Two diagrams show the battery holder: one empty with '+' and '-' markings indicating polarity, and one with two AAA batteries correctly inserted according to polarity.

Insert the batteries in the empty battery holder, ensuring that each battery is oriented for the correct polarity (+ / -). Push the battery holder back inside the thermostat until it is secured in its closed position.

Replacing the Batteries

Batteries have a fixed lifespan and will need to be replaced occasionally to ensure the thermostat operates correctly.

The thermostat will inform you when batteries need replacing by displaying a flashing battery icon on screen.

Note: You must replace the batteries within 1 minute of removal to retain the current clock and comfort level settings.

Image Description: The LCD display shows a flashing battery icon in the bottom right corner.

Pairing with RF Devices

This section covers pairing the thermostat with various receivers.

Pairing With the RF-Switch

If using with the UH8-RF wiring centre, refer to the relevant section.

With the thermostat turned OFF:

• Press & hold the ? (Clock) button until you see two sets of numbers appear. The small number 01 in the top right corner of the LCD is the feature number.
• Press ? (Clock) repeatedly until you see feature 06 (Receiver Type). The options are: 00 = UH8-RF or 01 = RF-Switch receiver.
• Use the ⬆️⬇️ [Up/Down Keys] to set feature 06 to 01 (RF-Switch).
• Press ? (Clock) again until you see feature 07 (Receiver Address).
• You can now select a Receiver Address from 01-32.
• Use the ⬆️⬇️ [Up/Down Keys] to set feature 07 to 01. (You must set a unique receiver address for each receiver installed).
• Press [A Button] to confirm settings and the display will go blank.
• If in mode 02, the hot water will automatically be paired to HW2.

Pairing the Thermostat (with RF-Switch Receiver)

• On the RF-Switch receiver, press and hold the CH1 Pairing button (if a valve is used) or Boiler CH Pairing button until the Comms LED flashes.
• With the thermostat turned OFF, press & hold the [A Button] for 5 seconds.
• The thermostat will send a signal for 1 minute and will flash the ? [RF Signal Icon].
• If pairing is successful, the Comms LED on the RF-Switch receiver will go out.
• Press the [Power Button] on the thermostat once to confirm pairing.

If pairing is unsuccessful, check features 06 to 07 have been configured correctly. To eliminate a possible signal issue, reposition the thermostat closer to the receiver and repeat the pairing process again.

Pairing With the UH8-RF Wiring Centre

On the UH8-RF, take note of the numbers set on the rotary switches (UH8-RF ID numbers 01-99). Each UH8-RF on the system needs to have a different ID number.

Set your first UH8-RF to 01.

Image Description: A diagram shows a rotary switch with numbers, illustrating how an ID number might be set (e.g., showing '99').

With the thermostat turned OFF:

• Press & hold the ? (Clock) button until 2 sets of numbers appear on screen. The small number 01 in the top right corner of the LCD is the feature number.
• Press ? (Clock) repeatedly until you see feature 06 (Receiver Type). The options are: 00 = UH8-RF or 01 = RF-Switch receiver.
• Use the ⬆️⬇️ [Up/Down Keys] to set feature 06 to 00 (UH8-RF).
• Press ? (Clock) again until you see feature 07 (UH8-RF Board Address).
• Use the ⬆️⬇️ [Up/Down Keys] to set the large digits to the board address of the UH8-RF. This is the number set on the UH8-RF rotary switches. (You must set a unique board address for each UH8-RF installed).
• Press ? (Clock) again until you see feature 08 (Zone number, 01-08).
• The UH8-RF is an 8 zone receiver. Use the ⬆️⬇️ [Up/Down Buttons] to select the zone this thermostat should be linked to.
• Press ? (Clock) again until you see feature 09 (00 = Underfloor heating, 01 = Radiators).
• Use the ⬆️⬇️ [Up/Down Buttons] to specify whether the thermostat is controlling underfloor heating or radiators.
• Press [A Button] to confirm settings and the display will go blank.
• Press the [Power Button] once to turn the thermostat back ON.
• Press the ⬆️ [Up Key] to set the target temperature above the room temperature; the ? [Flame Icon] will appear and the assigned zone on the UH8-RF will be activated. This indicates pairing between the thermostat and the UH8-RF is successful.

Pairing with the UH8-RF V2

Step 1 Setup. With the thermostat turned OFF:

• Press & hold the ? (Clock) button until you see two sets of numbers appear *. The small number 01 in the top right corner of the LCD is the feature number.
• Press ? (Clock) repeatedly until you see feature 06 (Receiver Type). The options are: 00 = UH8-RF or 01 = UH8-RF v2/RF-Switch receiver.
• Use the ⬆️⬇️ [Up/Down Keys] to set feature 06 to 01 (UH8-RF V2/RF-Switch).
• Press ? (Clock) again until you see feature 07 (Receiver Address). You can now select a zone number from 01-08. To save confusion, set this address to the same zone number you will be pairing to on the UH8-RF V2.
• Use the ⬆️⬇️ [Up/Down Keys] to set feature 07 to 01. (You must set a unique zone number address for each thermostat installed).
• Press [A Button] to confirm settings and the display will go blank. If in mode 02, the secondary timer will automatically be paired to Hot Water channel.

Step 2 Pairing.

• On the UH8-RF V2, press and hold the desired zone pairing button for 5 seconds or until the zone light flashes steadily.
• With the thermostat turned OFF, press & hold the [A Button] for 5 seconds.
• The thermostat will send a signal for 1 minute and will flash the ? [RF Signal Icon]**.
• If pairing is successful, the flashing light on the UH8-RF V2 will go out almost immediately.

If pairing is unsuccessful, check features 06 to 07 have been configured correctly. To eliminate a possible signal issue, reposition the thermostat closer to the receiver and repeat the pairing process again.

Image Description: Two LCD screen examples are shown: '*Feature Menu' displaying 'SET 00' and '01', and '**Active Pairing' displaying 'SET 00' and '01'.

LCD Display Explained

Image Description: A diagram of the thermostat's LCD screen with numbered callouts pointing to different display elements.

1. Room Temp: Indicates the current temperature sensor mode.

2. Day Indicator: Displays the current day (e.g., Sun, Mon, Tue).

3. Frost Icon (❄️): Displayed when the thermostat is in frost protection mode.

4. Flame Icon (?): Displayed when the thermostat is calling for heat; flashes when the Optimum Start function is in operation.

5. RF Icon (?): Flashes when the thermostat communicates with the receiver.

6. Temperature Hold: Displayed when manually overriding the program, showing "HOLD FOR" and the time period.

7. Set ([SET]): Displayed when changes are made to programs or temperature set points.

8. Holiday Indicator (?): Displayed when the programmer is in holiday mode.

9. Current Temp: Indicates the current sensor temperature.

10. Program Cycle Indicator: Displayed during programming only to show which period is being altered.

11. Battery Level (?): Indicates when the batteries require replacement.

12. Keypad Lock Indicator (?): Displayed when the keypad is locked.

13. Units of Temperature: Displays degrees Celsius (°C) or Fahrenheit (°F).

14. Timer Status: Displays the current state of the timed output (e.g., TIMER ON, TIMER OFF).

15. Clock: Digital clock display in 24h format.

Setting the Clock

To set the clock, follow these steps:

• With the thermostat turned ON, press the ? (Clock) key three times*.
• Use the ⬆️⬇️ [Up/Down Keys] to set the hours.
• Press [H Button] to confirm settings.
• Use the ⬆️⬇️ [Up/Down Keys] to set the minutes.
• Press [H Button] to confirm settings.
• Use the ⬆️⬇️ [Up/Down Keys] to set the day of the week.
• Press [A Button] to confirm settings and return to main display.

Image Description: An LCD display shows 'SET', '12:08', and labels for 'Day', 'Hours', and 'Minutes'.

*Note: When configured in programmable without hot water control (Feature 17 =01), press the clock key twice to enter the clock setting screen.

Temperature Display

The temperature display information is driven by two different inputs: the sensor measurement and the target temperature you have set.

Image Description: Two LCD examples are shown. The left shows 'ROOM TEMP 20 °C' with 'Wed' and '18:03h TIMER ON'. The right shows 'SET 22 °C'. Labels point to 'Room Temperature' and 'Set Temperature'.

The left display shows the current room temperature. The right display shows the temperature you are trying to achieve in your home.

Comfort Levels Explained

The thermostat provides Weekday/Weekend or 7 Day Programming options. Consult the "Optional Features" section to select the required mode.

The thermostat is supplied with comfort levels already programmed, but these can be changed easily. The default times and temperatures are:

• 08.00 - 21°C (Wake)
• 09.30 - 16°C (Leave)
• 16.30 - 22°C (Return)
• 23.00 - 17°C (Sleep)

If you only want to use 2 levels, program the unused levels to --.--.

Note: For Weekday/Weekend programming, the 4 comfort levels are the same for all weekdays but can be different for the weekends. For 7 Day programming, each day can have 4 different comfort levels.

To program comfort levels, press the ? (Clock) key once.

Image Description: Two LCD examples. The left shows 'Mon Tue Wed Thu Fri' with 'WAKE' and '22 °C' at '08:00'. The right shows 'Mon' with 'WAKE' and '22 °C' at '08:00'.

For Weekday/Weekend programming, Mon Tue Wed Thu Fri are displayed on screen. For 7 Day programming, only Mon is displayed in the day indicator field.

Follow these steps to program comfort levels:

• Use the ⬆️⬇️ [Up/Down Keys] to enter the required WAKE time.
• Press [H Button] to confirm settings.
• Use the ⬆️⬇️ [Up/Down Keys] to enter the required WAKE temperature.
• Press [H Button] to confirm settings.
• You will now see "LEAVE" displayed on screen.
• Repeat the programming steps for each period until complete.
• For unused periods, enter --.-- and the thermostat will ignore the setting.
• Press [A Button] to confirm settings and return to main display.

Note:

• In 7 Day programming mode, you can repeat for each day independently.
• In Weekday/Weekend programming mode, you will see Sat Sun displayed on screen and can repeat for the weekend.
• To change the programming mode, please refer to pages 27-30.

Locking the Thermostat

The thermostat has a keypad lock facility. To activate the lock, follow these steps:

• Press and hold the [A Button] and ⬇️ [Down Key] together for 10 seconds.
• You will see the ? [Lock Symbol] appear on screen.
• To unlock, repeat the steps above until the lock symbol disappears.

Note: The keypad lock indicator is only displayed when the lock is active.

Image Description: The LCD display shows 'ROOM TEMP 20 °C' with 'Wed', '18:03h TIMER ON', and a ? [Lock Symbol] in the bottom right corner, labeled as 'Keypad Lock Indicator'.

Temperature Control

The ⬆️⬇️ [Up/Down Keys] allow you to adjust the set temperature.

When you press either key, you will see the word SET and the desired temperature will be displayed on screen.

Use the ⬆️⬇️ [Up/Down Keys] to adjust the SET value.

Press [A Button] to confirm settings and return to main display.

Note: This override will be maintained until the next programmed comfort level.

Image Description: An LCD display shows 'SET' and '18 °C', labeled as 'Set Temperature' and 'Set Icon'.

Temperature Hold

The temperature hold function allows you to manually override the current operating program and set a different temperature for a desired period.

• Press [H Button] to commence temperature hold.
• Use the ⬆️⬇️ [Up/Down Keys] to enter the required Hold time.
• Press [H Button] to confirm settings.
• Use the ⬆️⬇️ [Up/Down Keys] to enter the required Hold temperature.
• Press [A Button] to confirm settings and return to main display.

You will see the "Hold For" indication displayed on screen. The time will countdown the set duration and then revert to the normal program.

Image Description: An LCD display shows 'SET', '16 °C', and 'HOLD FOR 01:00h'. Labels point to 'Hold ON Indicator' and 'Hold Time Remaining'.

To cancel temperature hold, follow the same steps but reduce the Hold time to 00:00 hours.

Holiday Mode

The holiday function reduces the set temperature in your home to the frost protection temperature setting (see page 27). The thermostat will maintain this temperature for the duration of the holiday and will then automatically return to the program schedule on your return.

• Press [H Button] three times (until you see the ? [Suitcase Icon] on screen).
• Use the ⬆️⬇️ [Up/Down Keys] to enter the number of days holiday.
• Press [A Button] to confirm settings and return to main display.

The display will show a suitcase indicating the thermostat is in holiday mode.

Note: A holiday period does not start until 00:00 the next day. For example, if you set a holiday period on Friday for 2 days, Saturday will be counted as the first day and the thermostat will revert back to the programmed schedule at 00:00 on Monday.

Image Description: An LCD display shows 'SET 02', labeled as 'Holiday Days Holiday' and 'ON Indicator'.

To cancel, follow the same steps but reduce the Holiday duration to 00 days.

Setting the Hot Water Switching Times

This function is only applicable when configured in programmable with hot water control (Feature 17 =02).

• Press the ? (Clock) key twice*.
• If your thermostat is setup for Weekday/Weekend programming, Mon-Fri will be displayed on screen. For 7 day programming, Mon will be displayed on screen.
• Using the ⬆️⬇️ [Up/Down Keys], enter the required start time for Hot Water Time 1.
• Press [H Button] to confirm settings.
• Use the ⬆️⬇️ [Up/Down Keys], enter the required end time for Hot Water Time 1.
• Press [H Button] to confirm settings.

Repeat the programming steps for each switching time, entering --.-- for any unused periods.

Image Description: An LCD display shows 'Mon Tue Wed Thu Fri' with '08:00' and 'TIMER ON', labeled as 'Time' and 'Timer Status'.

Hot Water Override

You can override the hot water setting by pressing the [A Button] key.

If the hot water is OFF, pressing the [A Button] key will switch the hot water ON. Similarly, pressing the [A Button] key when the hot water is ON will switch it OFF.

Timer ON or OFF will flash to show when the hot water has been overridden. This override will last until the next programmed setting.

Image Description: The LCD display shows 'ROOM TEMP 20 °C' with 'Wed', '18:03h TIMER ON', labeled as 'Timer Status'.

Frost Mode

Pressing the [Power Button] once will place the thermostat in frost protect mode.

In this mode, the thermostat will display the ❄️ [Frost Icon] and will only turn the heating on should the room temperature drop below the set frost temperature (see page 27).

Should the heating be turned on whilst in frost mode, the ? [Flame Icon] will be displayed.

To cancel the frost protect mode, press the [Power Button] once again.

Heating On/Off

The heating is indicated ON when the ? [Flame Icon] is displayed.

When the ? [Flame Icon] is absent, there is no requirement for heating to achieve the set temperature, but the thermostat remains active.

To turn the thermostat OFF completely, press and hold the [Power Button]. The display and heating output will be turned OFF completely.*

Press the [Power Button] once to turn the thermostat back ON.

*See Feature 3 on page 27.

Re-calibrating the Thermostat

If you need to re-calibrate the thermostat, follow these steps:

• Press and hold the [Power Button] to turn the thermostat OFF.
• Press and hold BOTH the [Power Button] and ⬇️ [Down Key] together until the temperature appears on the screen.
• Use the ⬆️⬇️ [Up/Down Keys] to configure the new temperature.
• Press [A Button] to confirm settings.
• Press the [Power Button] once to turn the thermostat back ON.

Factory Reset

The thermostat has a reset function to restore all settings to their factory defaults.

To perform a factory reset, follow these steps:

• Press and hold the [Power Button] to turn the thermostat OFF.
• Press and hold the [Power Button] and ⬆️ [Up Key] together until the LCD powers up. All of the icons will be displayed on screen.
• When the icons have disappeared from the screen, the thermostat has been successfully reset.
• Press the [Power Button] once to turn the thermostat back ON.

Optional Features Explained

FEATURES 1 - 4 AND 10 - 17 ARE OPTIONAL AND IN MOST CASES NEED NOT BE ADJUSTED.

• Feature 01 - Temperature Format: This function allows you to select between °C and °F.
• Feature 02 – Switching Differential: This function allows you to increase the switching differential of the thermostat. The default is 1°C, which means that with a set temperature of 20°C, the thermostat will switch the heating on at 19°C and off at 20°C. With a 2°C differential, the heating will switch on at 18°C and off at 20°C.
• Feature 03 – Frost Protect: You can set whether the thermostat will maintain the frost temperature when the thermostat display is turned off. As a default, this is enabled.
• Feature 04 – Frost Protect Temperature: This is the temperature maintained when the thermostat is in frost mode. The range is 07° - 17°C. The default is 12°C and is suitable for most applications.
• Feature 05 – Output Delay: To prevent rapid switching, an output delay can be entered. This can be set from 00 - 15 minutes. The default is 00, which means there is no delay.
• Feature 06 – UH8-RF or RF-Switch receiver: The thermostat can work with our UH8-RF V1 & V2 8 zone wiring centres or RF-Switch receiver. This setting determines which is being used.
• Feature 07 – Receiver Address: Within one building, up to 99 UH8-RF's, 32 RF-Switch's or 4 UH8-RF v2's can be used. Each RF-Switch must have a unique receiver address (01-32).
• Feature 08 – Zone Number (UH8-RF only): This is the zone number you are assigning the thermostat to on the UH8-RF, Zone 01 – 08.
• Feature 09 – Underfloor Heating or Radiator Zone (UH8-RF Only): This setting determines whether the thermostat will activate the pump & boiler output on the UH8-RF. If set to 00 the outputs will be activated. 00 = UFH, 01 = Radiators.
• Feature 10 – Fail Safe: If enabled, the thermostat will send a signal to the receiver every 20 minutes. Should the receiver fail to receive two signals, the receiver will activate the output for 20% of the time. This is to protect the system against a loss of wireless signal and in case the thermostat battery fails whilst you are away.
• Feature 11 – Temperature Up/Down Limit: This function allows you to limit the use of the up and down keys. This limit is also applicable when the thermostat is locked and so allows you to give others limited control over the heating system.
• Feature 12 – Air Sensor Selection: On this thermostat, you can select which sensor should be used - built-in sensor or remote air sensor.
• Feature 13 – Not used on this model.
• Feature 14 – Optimum Start: Optimum start will delay the start-up of the heating system to the latest possible moment to avoid unnecessary heating and ensure the building is warm at the programmed time. The thermostat uses the rate of change information to calculate how long the heating needs to raise the building temperature 1°C (with a rate of change of 20, the thermostat has calculated the heating needs 20 minutes to raise the building temperature 1°C) and starts the heating accordingly.
• Feature 15 – Rate of Change: For information only.
• Feature 16 - 5/2 Day or 7 Day Programming: The thermostat offers 2 programming methods. Weekday/Weekend allows you to program 4 comfort levels for the weekdays and 4 different comfort levels for the weekend. In 7 Day program mode, each day has 4 comfort levels that can be programmed independently.
• Feature 17 – Thermostat Mode: Here you can set in which mode you would like the thermostat to operate. The options are: manual (non-programmable), programmable, or programmable with hot water time clock.

Optional Settings - Feature Table