USER MANUAL

Introduction

The Drexma UDG thermostat is designed to control your heating system based on a pre-set schedule. It allows for individual temperature settings across four distinct periods (events) for each day of the week. The thermostat comes with a default schedule suitable for most installations. By lowering the temperature when the home is unoccupied, users can reduce energy costs without compromising comfort. The thermostat also features an adaptive function that automatically adjusts heating start times to ensure the desired temperature is reached at the scheduled time. This adaptive function learns the optimal heating start times after approximately three days of operation.

First Time Settings

Upon initial activation, the thermostat requires the current time and day to be set. The time will flash, prompting the user to adjust it using the [Up] and [Down] buttons, then confirm with the [OK] button. Subsequently, the day of the week will flash, allowing for similar adjustment and confirmation. Once set, the thermostat is ready to manage heating according to its programmed 4-event schedule.

Ground Fault Circuit Interrupter (GFCI)

The thermostat incorporates a built-in GFCI to ensure personal safety against ground faults. Regular monthly checks of the GFCI are recommended. Testing is only possible when the thermostat is actively calling for heat. The display will show the heating symbol [heating-symbol] when active. Adjust the setpoint using the [Up] button to increase heating demand, then press [OK]. After a 10-second adjustment period, press the TEST button. A successful test is indicated by the red light on the TEST button illuminating and 'GROUND FAULT' appearing on the display. If the test fails, check the installation or consult an electrician. The Standby/Reset button is used to reset the GFCI; the red light should extinguish, and the display should return to normal. Pressing the [Down] button returns to the original temperature setting. If the GFCI trips during normal operation without the TEST button being pressed, it may indicate a ground fault. Pressing Standby/Reset will help determine if it's a nuisance trip (red light goes off and stays off) or a genuine ground fault (red light does not stay off), in which case an electrician should be contacted.

Active Display

After one minute of inactivity, the display enters an idle mode, turning off the backlight. Pressing any button will reactivate the display.

Exit Menu

To exit any menu, navigate to the EXIT option using the [Up] or [Down] buttons until 'EXIT' flashes, then press the [OK] button. This may need to be repeated to reach the final EXIT option. When a menu is activated, the last selected item will flash, allowing you to review the previous setting. This principle also applies to current temperature and time settings, which are displayed as they were last selected.

4-Event Program

This feature allows automatic temperature control based on a daily program with four distinct events: Morning, Away, Home, and Night. Setting up the program involves three main steps:

Step 1: Select automatic temperature control.

With the display active, press [OK] to enter the menu. Navigate to MODE using [Up]/[Down] and press [OK]. Then, select AUTO mode using [Up]/[Down] and press [OK].

Step 2: Choosing the weekly schedule for your program.

Options include:

• 5:2: Four events (Morning, Out, Home, Night) for 5 days (Mon-Fri) and two events (Morning, Night) for 2 days (Sat-Sun).
• 6:1: Four events (Morning, Out, Home, Night) for 6 days (Mon-Sat) and two events (Day, Night) for 1 day (Sun).
• 7:0: Individual settings for each day of the week (Mon-Sun).

To select a schedule: With the display active, press [OK], navigate to SCHEDULE using [Up]/[Down] and press [OK]. Select the desired program (5:2, 6:1, or 7:0) and press [OK].

Step 3: Select the time and temperature settings for each event.

Navigate to PROGRAM using [Up]/[Down] and press [OK]. Select the day(s) to program. The first event's symbol will flash. Press [OK] to set the start time for the event (adjustable in 15-minute intervals) and then press [OK] to set the temperature. Repeat for all events. The thermostat display shows examples of setting times and temperatures for different events and days.

Quick Set Temperature

To permanently change the temperature for the currently active event in the automatic program, adjust the temperature using the [Up]/[Down] buttons and press [OK]. The new setting is saved for future use.

Adaptive Function

To ensure the desired temperature is reached by the scheduled time (e.g., upon waking or returning home), activate the adaptive function. Navigate to SETTINGS via [OK], then select ADAPTIVE. Choose ON and press [OK]. The function calculates the heating start time to meet the set temperature, learning over three days.

Manual Mode

To temporarily override the 4-event program and manually set a temperature, select MODE, then MAN. MODE. The temperature will flash, allowing adjustment with [Up]/[Down] and confirmation with [OK]. This mode is useful for specific situations like holidays.

Temporary Override

For a single event, temporarily set a comfort temperature (e.g., for a party or a day off). Select MODE, then OVERRIDE. Adjust the temperature using [Up]/[Down] and confirm with [OK]. This setting is temporary and will be cancelled by the next scheduled event.

Child Lock

To prevent unauthorized changes, activate the child lock. Navigate to SETTINGS, then CHILDLOCK. Select ON and press [OK]. A padlock symbol [lock-symbol] will appear on the display. To unlock, press and hold the [Up] and [Down] buttons simultaneously for three seconds.

Temperature Unit

Change the display unit between Celsius (°C) and Fahrenheit (°F). Navigate to SETTINGS, then °C/°F. Select the desired unit using [Up]/[Down] and press [OK]. Temperatures are displayed with 0.5°C resolution or 1°F resolution.

Setting Time

To adjust the time, navigate to SETTINGS, then TIME. Select 12 or 24-hour format using [Up]/[Down] and press [OK]. Set the hour, then the minutes, using [Up]/[Down] and confirming with [OK] after each. The display shows examples of time settings.

Setting Day

To change the day of the week, navigate to SETTINGS, then DAY. Select the current day using [Up]/[Down] and press [OK]. The display shows the days of the week for selection.

Read Out

View the heating usage percentage over a selected period (2, 30, or 365 days). Navigate to SETTINGS, then READOUT. Select the desired period. The submenu also provides software version and application control type information.

Offset Temperature

Adjust the temperature difference between the thermostat and a room thermometer. Navigate to SETTINGS, then OFFSET TEMP. Set the offset value (±10°C or ±18°F) using [Up]/[Down] and press [OK]. This compensates for discrepancies between the thermostat's reading and the actual room temperature.

Application

Select the type of temperature control: ROOM (uses built-in sensor), FLOOR (uses floor sensor), REGULATOR (no sensors), or ROOM LIMIT (uses external sensor as a limit). Navigate to SETTINGS, then APPLICATION. Choose the desired control type and press [OK]. For FLOOR or ROOM LIMIT, set maximum and minimum floor temperatures.

Display

Customize the information shown on the thermostat display. Navigate to SETTINGS, then DISPLAY. Options include showing/hiding the clock and set temperature, and selecting the displayed temperature source (Room, Floor, or Regulator).

Factory Reset

To restore factory default settings, navigate to SETTINGS, then FACTORY RESET. Select RESET and press [OK].

Error Messages

The thermostat may display error codes:

• E0: Internal failure. Replace thermostat.
• E1: Internal sensor defective or short-circuited. Replace thermostat.
• E2: External sensor defective or short-circuited. Check external sensor.

Factory Settings for Automatic 5:2 Program

The default program settings for a 5:2 schedule are:

Days 1-5 (Monday - Friday)

Days 6-7 (Saturday - Sunday)