Heatmiser PRT-WTS Wireless Series Programmable Room Thermostat

What is a Programmable Room Thermostat?

A programmable room thermostat functions as both a programmer and a room thermostat. The programmer allows you to set 'On' and 'Off' periods to suit your lifestyle. The room thermostat senses the air temperature, activating the heating when the temperature drops below the set point and deactivating it once the set temperature is reached.

This means you can choose when your heating is active and the temperature it should reach. You can set different temperatures for different times of the day and days of the week to meet your specific needs.

Setting a higher temperature will not make the room heat up faster; heating speed depends on the system's design and size. Similarly, lowering the temperature setting does not affect how quickly a room cools down. A lower setting results in the room being controlled at a lower temperature, saving energy.

The most effective way to use your thermostat is to identify the lowest comfortable temperatures for different times and then let the thermostat manage them. A recommended approach is to set a low temperature (e.g., 18°C) and increase it by 1°C daily until comfortable, avoiding further manual adjustments that waste energy.

For homes with a boiler and radiators, a single thermostat typically controls the entire house. However, individual room temperatures can be managed using Thermostatic Radiator Valves (TRVs). If TRVs are not installed, set a temperature suitable for the whole house. With TRVs, a slightly higher setting can ensure the coldest room is comfortable, while TRVs prevent overheating in others.

Temporary adjustments to the heating program can be made via overriding or the temperature hold feature, explained on pages 14 and 15 of this manual.

Programmable thermostats require unobstructed airflow for accurate temperature sensing. Avoid covering the thermostat with curtains or furniture. Nearby heat sources like electric fires, televisions, or lamps can also interfere with its operation.

Installation Procedure

Do

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

Don't

• ❌ Do not push hard on the LCD screen as this may cause irreparable damage.
• ❌ Do not install near a direct heat source, as this will affect functionality.
• If using the desk stand, ensure the thermostat is away from heat sources.

Wall Mounting:

1. Step 1: Fix the wall plate to the wall.
2. Step 2: Push the thermostat onto the wall plate.

Desk Stand:

1. Step A: Remove the thermostat from the wall plate.
2. Step B: Release and attach the desk stand.

Diagram Description: The installation section includes diagrams illustrating wall mounting (attaching a wall plate and then the thermostat) and desk stand setup (detaching from wall plate and attaching to stand).

LCD Display

Diagram Description: A detailed diagram of the Heatmiser PRT-WTS LCD display with numbered callouts:

• 1. Day Indicator: Displays the current day.
• 2. Holiday Indicator: Shown when the thermostat is in Holiday mode.
• 3. Temperature Hold: Shown when the thermostat is in Hold mode.
• 4. Clock: Displays the time in normal operation, time left in hold, or days left in holiday mode.
• 5. Up/Down Buttons (top group): Increase or decrease values on the top digit group.
• 6. Flame Icon (?): Displayed when the thermostat is calling for heat; flashes when optimum start is active.
• 7. Keypad Lock Icon (?): Shown when the keypad is locked.
• 8. Zone Indicator: Displays which zone the thermostat is linked to.
• 9. Frost Icon (❄️): Displayed when the thermostat is in frost protection mode.
• 10. RF Icon (?): Flashes when communicating with the receiver.
• 11. Battery Icon (?): Indicates current battery charge level.
• 12. Room Temp: Indicates the current temperature sensor mode.
• 13. Set: Indicates when changes are being made to programs or set points.
• 14. Clean Screen: Freezes the screen for 15 seconds for cleaning.
• 15. Up/Down Buttons (bottom group): Increase or decrease values on the bottom digit group.
• 16. Power (⏻): Single press to enable/disable frost protection; press and hold to turn off display. Cancel: Used to exit setup/program operations.
• 17. Setup/Programming Buttons: Used to navigate setup options.
• 18. Current Temp: Indicates the current sensor temperature.
• 19. Units of Temperature: Degrees Celsius (°C) or Fahrenheit (°F).
• 20. Comfort Level Selection Buttons: Used in comfort level setup.

Pairing the Thermostat

To pair the thermostat with the RC1-WTS receiver, follow these steps:

On the receiver:

• Press the Pair button once. The Communication LED will light up.

On the thermostat:

1. Press [PROG] and then [SETUP].
2. At the top of the LCD, '01' will appear.
3. Use the Up key (▲) to select '05' and enter the pairing function.
4. Press [ZONE 1] or [ZONE 2] to select the relevant zone. (Two PRT-WTS units can work with a single receiver for a two-zone system).
5. In the center of the LCD, '01' will appear, representing the channel address. This default can be used in most cases but may need changing if conflicts with other RF devices occur.
6. Use the Up/Down keys (▲▼) to enter the desired channel address.
7. Press [SETUP] to pair the thermostat and receiver.

Note: You must finish pairing before the receiver's communication LED goes out.

Pair Successful: The receiver's Comms LED will flash and then go out, indicating successful pairing. The thermostat will display the communication icon (?).

Pair Fail: If the Comms LED does not flash, there may be an RF signal problem. Reduce the distance between the thermostat and receiver, and ensure no metal objects are blocking the signal. The LED will automatically turn off after 1 minute.

Diagram Description: Shows the PRT-WTS thermostat and the RC1-WTS receiver with its controls and Comms LED.

Setting the Clock

To set the clock, follow these steps:

• Press [PROG].
• Press [CLOCK].
• Use the Down key (▼) to set the hours.
• Use the Up key (▲) to set the minutes.
• Use the [DAY] key to set the day of the week.
• Press [DONE] to confirm and exit.

Diagram Description: Illustrates the clock setting interface on the thermostat, showing fields for Day, Hours, and Minutes, with corresponding adjustment buttons.

Temperature Display

The temperature display information is derived from two inputs: the sensor measurement and the target temperature you have set.

Diagram Description: Two thermostat display examples are shown. The left screen, labeled 'Room Temperature', displays the current time (20:38) and the current room temperature (22.0°C). The right screen, labeled 'SET Temperature', displays the target temperature (22°C) you are trying to achieve in your home.

Comfort Levels Explained

Comfort levels allow you to set different temperatures throughout the day. For example, you might want your home warm in the morning, cooler when unoccupied during the day, and warmer again in the evening.

The thermostat offers two programming options:

• 5/2 Day Programming: 4 levels for weekdays and 4 different levels for weekends.
• 7 Day Programming: 4 levels for each day.

Refer to pages 23-24 for details on switching between these modes.

Tip! If you don't wish to use all comfort levels, set the time to '--:--'. Default comfort levels are pre-programmed but can be changed.

Weekday Level:

• Wake: 07:00, 21°C
• Leave: 09:00, 16°C
• Return: 16:00, 21°C
• Sleep: 22:00, 16°C

Weekend Level:

• Wake: 09:00, 21°C
• Leave: 22:00, 16°C
• Return: --:--, --°C
• Sleep: --:--, --°C

To program comfort levels:

1. Press [PROG].
2. Select [WAKE].
3. Use the Up/Down keys (▲▼) to set the time for the WAKE period.
4. Use the Up/Down keys (▲▼) to set the temperature.
5. Repeat these steps for the [LEAVE], [RETURN], and [SLEEP] periods.
6. Press [DAY] to select the next day to program and repeat.

In 5/2 Day mode, the thermostat will display 'Sat Sun' prompting you to program weekend temperatures. In 7 Day mode, it will display 'Tue'.

When complete, press [DONE] to confirm settings and exit.

Diagram Description: Shows thermostat displays for programming comfort levels in 5/2 Day mode ('Sat Sun') and 7 Day mode ('Tue').

Clean Screen

Pressing the [SCREEN] button disables all keys for 15 seconds, allowing you to wipe the screen clean before the keys are re-activated.

Locking the Keypad

The thermostat features a keypad lock facility.

• To activate the lock, press and hold the bottom right corner of the display for 10 seconds.
• When activated, the Keypad Lock Icon (?) will be displayed.
• To cancel, press and hold the bottom right corner of the display again for 10 seconds.

Diagram Description: A thermostat display example shows 'SAT 20:38' and 'ROOM TEMP 20.8°C', with the 'Keypad Lock Indicator' (?) visible.

Temperature Control

The Up/Down arrow keys (▲▼) under the temperature display allow you to adjust the set temperature. When pressed, the temperature and the word [SET] appear on screen.

Select the desired temperature and press [DONE] to confirm and exit.

Note: This manually set temperature is maintained only until the next programmed comfort level. At that point, the thermostat reverts to the programmed levels.

Diagram Description: A thermostat display shows 'SET 22°C' with up/down arrows (▲▼) and the 'Set Icon'.

Temperature Hold

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

• Press [HOLD].
• Use the top set of Up/Down keys (▲▼) to set the hold period.
• Use the center set of Up/Down keys (▲▼) to set the hold temperature.
• Press [DONE] to confirm and exit.

To cancel a temperature hold, follow the same steps but set the time to 00:00.

Diagram Description: A thermostat display shows 'HOLD 00:30 HRS', 'SET 22°C', with labels for 'Hold Icon', 'Hold Time', and 'Hold Temperature'.

Holiday

The holiday function reduces the set temperature to the frost protection setting (see page 21) for the duration of your holiday. The thermostat will automatically return to the program mode upon your return.

• Press [HOLIDAY].
• Enter the desired duration in days.
• Press [DONE] to confirm settings and exit.

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

To cancel a Holiday setting, reduce the holiday time to 00 days.

Diagram Description: A thermostat display shows 'HOLIDAY 02 DAYS', 'SET 02°C', with labels for 'Holiday Icon' and 'Holiday Days'.

Frost Mode

Pressing the [Frost Icon] (❄️) key once places the thermostat in frost protection mode. In this mode, the thermostat displays the frost icon and only turns on heating if the room temperature drops below the set frost temperature (see page 21). If heating is activated in frost mode, the flame symbol (?) will be displayed.

To cancel frost protect mode, press the [Frost Icon] (❄️) key once.

Diagram Description: A thermostat display shows 'MON ZONE 1 18:03' and 'ROOM TEMP 20.8°C', with the 'Frost Protection Mode Enabled' indicator.

Heating On/Off

The heating is indicated ON when the flame icon (?) is displayed. When the flame icon is absent, heating is not required to achieve the set temperature, but the thermostat remains active.

• To turn the thermostat OFF completely, press and hold the Power key (⏻). The display and heating output will turn off.
• To turn the thermostat back ON, press the Power key (⏻) once.

Diagram Description: Two thermostat screen examples are shown. The left screen indicates 'Thermostat completely OFF' (blank). The right screen shows 'Thermostat powered ON' with 'FRI 09:38' and 'ROOM TEMP 20.9°C'.

Optional Features Explained

The following settings are optional and generally do not require adjustment.

• Feature 01 – Temperature Format: Allows selection between °C or °F.
• Feature 02 – Switching Differential: Adjusts the temperature difference at which the thermostat switches heating on/off. The default is 1°C (heating switches on 1.0°C below set temp). A 2°C differential switches on 2°C below set temp.
• Feature 03 – Frost Temperature: The temperature maintained in frost mode (range 07-17°C). Default is 12°C.
• Feature 04 – Output Delay: Prevents rapid switching. Can be set from 00-15 minutes; default is 00 (no delay).
• Feature 05 – Pairing Function: Allows the thermostat to be paired with the receiver.
• Feature 06 - Fail Safe: If enabled, the thermostat sends a signal every 20 minutes. If the receiver fails to get the signal, it activates the output for 20% of the time to protect the system against signal loss or battery failure.
• Feature 07 – Optimum Start: Delays heating start-up to the latest possible moment, ensuring the building is warm at the programmed time by calculating heat-up duration.
• Feature 08 – Rate Of Change: The number of minutes the thermostat calculates it takes to raise the building temperature by 1°C. The thermostat learns this to optimize heating efficiency.
• Feature 09 - Programming Mode: Offers 2 methods: Weekday/Weekend (4 levels for weekdays, 4 for weekends) or 7 Day (4 levels for each day independently).

Adjusting the Optional Settings

To adjust optional settings, follow these steps:

• Press [PROG].
• Press [SETUP].
• Use the Up/Down keys (▲▼) at the top of the screen to select the feature number.
• Use the Up/Down keys (▲▼) in the center to adjust the setting value.
• Press [DONE] to confirm settings and exit.

Diagram Description: A thermostat display shows 'Feature Number 01' and 'Setting Value 00°C', with up/down arrows (▲▼) for adjustment.

Optional Settings - Feature Table

Battery Recharging

The thermostat is equipped with a rechargeable battery that can provide power for up to 6 months under normal operating conditions before recharging is required.

To recharge the battery, connect the thermostat to a power source using the supplied mini USB to USB lead. You can recharge from a USB port on your laptop or PC.

Diagram Description: Illustrates battery recharging. A USB cable (Part ref: USB-02) is shown connecting the thermostat to a power source, such as a laptop or PC USB port.

Re-calibrating the Thermostat

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

• Press and hold the Power key (⏻) to turn the thermostat OFF.
• Press and hold the [OFF] key until the temperature appears on screen.
• Use the Up/Down keys (▲▼) to configure the new temperature.
• Press [DONE] to confirm settings and exit.
• Press the Power button key (⏻) to turn the thermostat back ON.

Diagram Description: A thermostat display shows 'SET 25.0°C' with labels for 'Calibration Temperature' and 'Set Icon'.

Factory Reset

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

To perform a factory reset:

• Press & hold the Power key (⏻) to turn the thermostat display OFF.
• Press and hold the bottom left corner of the LCD for 10 seconds.
• All screen icons will appear for 2 seconds and then disappear.
• Press the Power key (⏻) once to turn the thermostat display back ON.

Diagram Description: The display shows all icons simultaneously for a brief period, then clears, indicating the factory reset is complete.

Notes

This section provides blank space for user notes.

Contact and Further Information

Heating Professionals: Request a copy of our product installation guide containing detailed technical specifications for our complete product range at: www.heatmiser.com/guide

Want More Information?

• Call our support team on: +44 (0)1254 669090
• View technical specifications directly on our website: www.heatmiser.com

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