Heatmiser PRT-EW Wireless Thermostat

What is a Programmable Room Thermostat?

A programmable room thermostat functions as both a programmer and a room thermostat. A programmer allows users to set 'On' and 'Off' periods to suit their lifestyle. A 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 allows you to define when the heating is active and at what temperature. You can select different temperatures for different times of the day and days of the week to meet your specific needs and preferences.

Setting a higher temperature on a programmable room thermostat does not accelerate the heating process; the speed depends on the design and size of the heating system. Similarly, reducing the temperature setting does not affect how quickly the room cools down. Setting a lower temperature results in the room being controlled at a lower temperature, leading to energy savings.

The most effective way to use your programmable room thermostat is to identify the lowest comfortable temperature settings for different times and allow the thermostat to manage the system. It is recommended to start with a lower temperature (e.g., 18°C) and gradually increase it by 1°C daily until comfort is achieved, avoiding further adjustments that waste energy.

Temporary adjustments can be made via overriding or using the temperature hold feature, detailed on pages 18 and 19. Programmable room thermostats require unobstructed airflow for accurate temperature sensing; avoid covering them with curtains or blocking them with furniture. Nearby heat sources like electric fires, televisions, or lamps can also affect performance.

Installation Procedure

Do: Mount the thermostat at eye level. Read instructions thoroughly for optimal product use.

Don't: Install near a direct heat source, as this impacts functionality. Do not apply excessive pressure to the LCD screen, as this can cause irreparable damage.

This wireless thermostat is designed for surface mounting.

Steps:

1. Carefully separate the front half of the thermostat from the back plate using a small flat-head terminal driver in the slots on the bottom face.
2. If installing a remote air temperature probe, terminate the thermostat as shown on page 29. Mark two hole positions on the wall using the backplate as a template. Drill at the marked positions and insert wall plugs.
3. Securely screw the thermostat back plate to the wall.
4. Clip the front of the thermostat back onto the back plate.

Diagram Description: Four images illustrate the installation steps: 1. The thermostat unit. 2. The backplate with battery compartment. 3. Inserting batteries into the backplate. 4. Attaching the front unit to the backplate.

Installing the Batteries

This thermostat is supplied with 2x AAA batteries. To access the battery holder, push and release the compartment door located on the bottom face of the thermostat.

Insert the batteries into the holder, ensuring correct polarity (+/-). Push the battery holder back into the thermostat until it is secured.

Diagram Description: Images show AA batteries being inserted into the battery compartment.

Replacing the Batteries

Batteries have a finite lifespan and require occasional replacement to ensure correct thermostat operation. The thermostat will indicate when batteries need replacing via a battery icon (?) on the screen.

Note: Batteries must be replaced within 1 minute of removal to retain current clock and comfort level settings.

Configuring the Thermostat

With the thermostat turned OFF:

• Press and hold the Clock button (⏰) until the LCD screen activates. Feature 01 will appear in the top right corner.
• Press the Clock button again to access Feature 07 (Receiver Address).
• Use the Up/Down arrow keys (▲/▼) to set the address. A unique address (01-32) is required for each receiver. Setting the address to 00 disables RF communication.
• Press the 'A' button (?️) to confirm settings; the display will go blank.

Pairing the RC2-W Receiver

• On the receiver, press and hold the Pairing button until the Comms LED illuminates.
• With the thermostat turned OFF, press and hold the 'A' button (?️) for 5 seconds.
• The thermostat will transmit a signal for 1 minute, and the RF icon (?) will flash.
• Successful pairing is indicated by the receiver's Comms LED flashing.
• Press the Power button (?) on the thermostat once to confirm pairing.

If pairing fails, verify Feature 07 is correctly configured. To resolve potential signal issues, reposition the thermostat closer to the receiver and repeat the pairing process.

LCD Display

The thermostat's LCD screen displays various information:

1. Room Temp: Indicates the current temperature sensor mode.
2. Day Indicator: Displays the current day (e.g., Sun, Mon).
3. Frost Icon (❄️): Shown when the thermostat is in frost protection mode.
4. Flame Icon (?): Displays when the thermostat is calling for heat; flashes during Optimum Start operation.
5. RF Icon (?): Flashes during communication with the receiver.
6. Temperature Hold: Displays when manually overriding the program, showing 'HOLD FOR' and the duration.
7. Set: Appears when program or temperature set points are changed.
8. Holiday Indicator (?): Shown when the programmer is in holiday mode.
9. Current Temp: Indicates the current sensor temperature.
10. Program Cycle Indicator: Shows which period is being altered during programming.
11. Battery Level (?): Indicates when batteries require replacement.
12. Keypad Lock Indicator (?): Displays when the keypad is locked.
13. Units of Temperature: Shows degrees Celsius (°C) or Fahrenheit (°F).
14. Clock: Digital clock display in 24-hour format.

Diagram Description: A labeled diagram illustrates the various icons and indicators on the thermostat's LCD screen.

Setting the Clock

To set the clock:

• With the thermostat ON, press the Clock button (⏰) twice.
• Use the Up/Down arrow keys (▲/▼) to set the hours, then press 'H' (?) to confirm.
• Use the Up/Down arrow keys (▲/▼) to set the minutes, then press 'H' (?) to confirm.
• Use the Up/Down arrow keys (▲/▼) to set the day of the week, then press 'A' (?️) to confirm and return to the main display.

Diagram Description: Shows labels for Day, Hours, and Minutes on the display.

Temperature Display

The temperature display shows information from two sources: the sensor measurement and the target temperature you have set.

Diagram Description: Two examples of the thermostat display are shown: one for 'Room Temperature' and one for 'Set Temperature'.

Comfort Levels Explained

The thermostat supports Weekday/Weekend or 7 Day Programming options. Consult the 'Optional Features' section for mode selection. Default comfort levels are pre-programmed but can be adjusted:

• Wake: 08:00 - 21°C
• Leave: 09:30 - 16°C
• Return: 16:30 - 22°C
• Sleep: 23:00 - 17°C

For Weekday/Weekend programming, all weekdays share the same 4 comfort levels, with separate levels possible for weekends. For 7 Day programming, each day can have 4 distinct comfort levels.

To program comfort levels:

• Press the Clock button (⏰) once.
• Use the Up/Down arrow keys (▲/▼) to enter the required WAKE time, then press 'H' (?) to confirm.
• Use the Up/Down arrow keys (▲/▼) to enter the required WAKE temperature, then press 'H' (?) to confirm.
• The display will show 'LEAVE'. Repeat the programming steps for each period.
• For unused periods, enter '--.--'.
• Press 'A' (?️) to confirm settings and return to the main display.

Notes:

• In 7 Day mode, each day can be programmed independently.
• In Weekday/Weekend mode, Sat/Sun are displayed for weekend programming.
• Refer to pages 24-26 to change the programming mode.

Diagram Description: Examples show the thermostat display for Weekday/Weekend programming (showing Mon-Fri) and 7 Day programming (showing only Mon).

Locking the Thermostat

The thermostat features a keypad lock. To activate:

• Press and hold the 'A' (?️) and Down (▼) keys together for 10 seconds. The lock symbol (?) will appear on screen.
• To unlock, repeat these steps until the lock symbol disappears.

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

Diagram Description: Shows the thermostat display with the lock symbol (?).

Temperature Control

Use the Up/Down arrow keys (▲/▼) to adjust the set temperature. The display will show 'SET' and the desired temperature.

Use the Up/Down arrow keys (▲/▼) to adjust the SET value. Press 'A' (?️) to confirm settings and return to the main display.

Note: This override will remain active until the next programmed comfort level.

Diagram Description: Shows the thermostat display with 'SET' and the target temperature.

Temperature Hold

The Temperature Hold function allows manual override of the current program with a different temperature for a specified period.

• Press 'H' (?) to commence temperature hold.
• Use the Up/Down arrow keys (▲/▼) to enter the required Hold time, then press 'H' (?) to confirm.
• Use the Up/Down arrow keys (▲/▼) to enter the required Hold temperature, then press 'A' (?️) to confirm and return to the main display.

The display will show 'Hold ON Indicator' and 'Hold Time Remaining', counting down the duration before reverting to the normal program.

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

Diagram Description: Shows the thermostat display with 'Hold ON Indicator' and 'Hold Time Remaining'.

Holiday

The Holiday function reduces the set temperature to the frost protection setting (see page 23) for the duration of your absence. The thermostat will automatically return to the program schedule upon your return.

• Press 'H' (?) three times until the suitcase icon (?) appears.
• Use the Up/Down arrow keys (▲/▼) to enter the number of holiday days, then press 'A' (?️) to confirm and return to the main display.

The display will show a suitcase icon (?) indicating holiday mode. A holiday period commences at 00:00 the following day. For example, a holiday set on Friday for 2 days will count Saturday as the first day, with the thermostat reverting to the schedule at 00:00 on Monday.

To cancel, follow the same steps but set the holiday duration to 00 days.

Diagram Description: Shows the thermostat display indicating 'Holiday Days' and a 'Holiday ON Indicator'.

Frost Mode

Pressing the Power button (?) once activates frost protect mode. The thermostat displays the frost icon (❄️) and will only activate heating if the room temperature drops below the set frost temperature (see page 23). If heating is active in frost mode, the flame icon (?) will be displayed.

To cancel frost protect mode, press the Power button (?) again.

Diagram Description: Shows the thermostat display with the frost protection mode enabled.

Heating On/Off

Heating is indicated as ON when the flame icon (?) is displayed. If the flame icon is absent, no heating is required to meet 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. To turn it back ON, press the Power button (?) once.

Diagram Description: Two images show the thermostat display: one completely OFF, and one powered ON with the flame icon.

*See Feature 03 on page 23.

Optional Features Explained

The following settings are optional and typically do not require adjustment:

• Feature 01 - Temperature Format: Select between °C and °F.
• Feature 02 - Switching Differential: Adjusts the thermostat's switching differential. Default is 1°C (heating on at 19°C, off at 20°C for a 20°C setpoint). A 2°C differential means heating on at 18°C, off at 20°C.
• Feature 03 - Frost Protect: Enables frost temperature maintenance when the display is off. Default is enabled.
• Feature 04 - Frost Protect Temperature: Sets the temperature maintained in frost mode (07°C - 17°C). Default is 12°C.
• Feature 05 – Output Delay: Sets a delay (00-15 minutes) to prevent rapid switching. Default is 00 minutes.
• Feature 06 – Not used on this model.
• Feature 07 – Receiver Address: Assigns a unique address (01-32) for each RC2-W receiver in a building.
• Feature 08, 09 – Not used on this model.
• Feature 10 – Fail Safe: If enabled, sends a signal every 20 minutes. If two signals are missed, the receiver activates the output for 20% of the time to protect the system from signal loss or battery failure.
• Feature 11 – Up/Down Temperature Limit: Limits the use of the Up/Down keys, useful when the thermostat is locked for controlled access.
• Feature 12 – Air Sensor Selection: Choose between the built-in sensor or a remote air sensor. A floor sensor must be connected to the receiver to operate.
• Feature 13 – Floor Limit: Uses the floor limiting sensor connected to the receiver to prevent floor overheating. The limit is set via the thermostat (20-45°C, default 28°C) and stored in the receiver. The receiver limits floor temperature if the RF link fails.
• Feature 14 – Optimum Start: Delays heating startup to ensure the dwelling is warm by the programmed time, avoiding unnecessary heating. It calculates the time needed to raise the temperature by 1°C based on the 'Rate of Change' setting. Optimum start functions on Wake and Return comfort levels.
• Feature 15 - Rate of Change: Defines minutes required to raise the temperature by 1°C.
• Feature 16 - Program Mode: Selects between Weekday/Weekend (4 comfort levels for weekdays, 4 for weekends) or 7 Day programming (4 comfort levels per day).

Adjusting the Optional Settings

To adjust optional settings:

• Turn the thermostat OFF by pressing and holding the Power button (?).
• Press and hold the Clock button (⏰) until the display shows the feature number and setting value.
• Use the Clock button (⏰) to cycle through features.
• Use the Up/Down arrow keys (▲/▼) to change the setting.
• Press 'A' (?️) to confirm settings.
• Turn the thermostat back ON by pressing the Power button (?) once.

Diagram Description: Shows the thermostat display interface for adjusting settings, indicating 'Setting Value' and 'Feature Number'.

Optional Settings - Feature Table

Re-calibrating the Thermostat

If re-calibration is necessary:

• Turn the thermostat OFF by pressing and holding the Power button (?).
• Press and hold both the Power (?) and Down (▼) keys until the temperature appears on the screen.
• Use the Up/Down arrow keys (▲/▼) to set the new temperature.
• Press 'A' (?️) to confirm settings.
• Turn the thermostat back ON by pressing the Power button (?) once.

Diagram Description: Shows the thermostat display for 'Calibration Temperature Setting' with a 'Set Icon'.

Factory Reset

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

To perform a factory reset:

• Turn the thermostat OFF by pressing and holding the Power button (?).
• Press and hold both the Power (?) and Up (▲) keys until the LCD powers up. All icons will be displayed simultaneously.
• The thermostat is successfully reset when the icons disappear from the screen.
• Turn the thermostat back ON by pressing the Power button (?) once.

Diagram Description: Shows all icons displayed simultaneously, indicating that a factory reset is complete.

Wiring Diagram - Remote Air Sensor

To enable the remote air probe, set Feature 12 to 01.

Diagram Description: A diagram shows the connections for a 'REMOTE AIR PROBE' with red and white wires connecting to terminals.

Notes

Space for user notes.

Heating Professionals

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