Computherm Q3 User manual

COMPUTHERM Q3
digital room thermostat
Operating Instructions

GENERAL DESCRIPTION OF THE THERMOSTAT
The COMPUTHERM Q3 type switched-mode room thermostat
is suitable to regulate the overwhelming majority of boilers available in
Hungary. It can easily be connected to any gas boiler or air conditioning
device that has a double wire connector for a room thermostat,
regardless of whether it has a 24 V or 230 V control circuit.
Temperature can be measured more precisely as compared
to simple, conventional thermostats. In accordance with the
selected switching sensitivity, the thermostat will switch the boiler
or any other appliances on and off below and above the adjusted
temperature, respectively, and contributes to reduce energy costs
while maintaining comfort.
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The switching sensitivity of the thermostat is ± 0.2°C (± 0.3°C). This
means the difference between the adjusted temperature and the
actual temperature
measured during the
switching process.
For example, if
the factory default
setting is 20°C on
the thermostat, then
the device switches
the boiler on at
19.8°C or below,
and switches it off at
20.2°C or above.
The information shown on the liquid
crystal display of the thermostat
includes the following:
Temperature
display
Temperature
measurement unit
Room
temperature
Set temperature
Heating mode
Defrosting
mode
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1. LOCATION OF THE DEVICE
It is reasonable to locate it in a room used regularly or for many
hours per day so that it is in the direction of natural ventilation in the
room but protected from drought or extreme heat (e.g. direct sunlight,
refrigerator, chimney, etc). Its optimal location is 1.5 m above floor
level.
IMPORTANT WARNING!
If the radiator valves in your flat are equipped with a thermostatic
head, replace the thermostatic head of the radiator valve with
manual control knob or adjust it to maximum temperature in the
room where the room thermostat is to be located, otherwise the
thermostatic head may disturb the temperature control of the flat.
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2. INSTALLATION OF THE THERMOSTAT
• To install the thermostat, detach the rear
panel of the thermostat from the front panel
by loosening the screws at the bottom of the
cover as shown in the figure.
• With the help of the screws provided and
some tools fasten the rear panel of the
device to the wall.
• Usingasmallscrewdriver,removethecover
of the terminal block from the inner side of
the rear panel.
• Theoutputrelayofthethermostathasthreepotential-freeconnection
points, i.e. No. 1(NO); No. 2(COM) and No. 3(NC), which are
located under an inner cover on the inner side of the rear panel. To
control heating, connect the two connection wires of the device to
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be controlled to terminals No. 1(NO) and No. 2(COM),
i.e. to the normally open terminals of the relay, while the
two connection wires of the cooling equipment should be
connected to terminals No. 2(COM) and No. 3(NC), i.e.
to the normally closed terminals of the relay.
• To prevent electric shock, replace the inner cover
removed for the connection of wires after the assembling
process has been completed.
Attention! The device must be installed and connected
by a qualified professional. Always follow the manufacturer’s
instructions when connecting the thermostat to any heating or
cooling appliance. The voltage appearing at terminal No. 1, No. 2
or No. 3depends only on the system being controlled, therefore
the dimensions of the wire are determined by the type of the device
to be controlled. The length of the wire is of no significance.
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3. PUTTING THE THERMOSTAT INTO OPERATION
To put the thermostat into operation, detach the rear panel of
the thermostat from the front panel by loosening the screws at the
bottom of the cover as shown in the figure.
The battery compartment is in the inner side of the front
panel of the housing. Insert 2 AA alkaline batteries (LR6 type)
in accordance with the diagram in the battery compartment.
After the batteries have been inserted, the display flashes the
measured room temperature. (If this information fails to appear
on the display, press the „ReSet” button with a wooden or plastic
stick. To press the button, do not use any electrically conductive
materials or graphite pencil).
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4. DEFAuLT SETTINGS
After removing the rear panel
of the device, the following factory
default settings can be modified
by relocating the jumpers (black
plugs) located on the base panel.
4.1 Modifying the Switching
Sensitivity
The switching sensitivity of the thermostat can be selected or
adjusted by the uppermost jumper.
The factory default switching sensitivity (the difference between
the adjusted temperature and the temperature measured when
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the device is switched on or off) is ±0.2°C that can be modified to
±0.3°C by relocating the plug onto the left and central pins.
4.2 Changing the Unit of Measurement of the Displayed Temperature
The unit of measurement of the temperature shown on the LCD
display can be selected and set by the central jumper.
Withfactorydefaultsettingsthedisplayshowsthetemperaturein
°C (Celsius) which can be modified to °F (Fahrenheit) by relocating
the plug onto the left and central pins.
4.3 Changing the Displayed Temperature
The temperature(s) to be shown on the LCD display can be
selected and set by the bottommost jumper.
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With factory default settings the display shows the currently
measured room temperature value, while the notice “RooM” appears
in the bottom right corner of the display. The adjusted temperature
is visible only during the adjustment process (for approximately 15
seconds). By relocating the plug onto the left and central pins the
displayed temperature can be modified so that the display alternately
shows the current room temperature and the adjusted temperature
for 4 seconds, respectively. In this mode, notices “RooM” and “Set”
are alternately shown under the currently displayed temperature in
the bottom right corner of the display, indicating whether the display
shows the room temperature or the adjusted temperature value.
ATTeNTION! To modify the factory default settings after inserting
the batteries, press the “Reset” button with a small wooden or plastic
stick to activate them.
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5. SETTING THE dESIREd TEMPERATURE
The factory default temperature was set to 20°C and in case of
the default switching sensitivity (± 0.2°C), the thermostat switches
on and off the connected heating appliance below 19.8°C and above
20.2°C, respectively. This default temperature can be freely changed
in steps of 0.5°C between 10°C and 30°C as follows:
Press the or button and the notice „• Set” (adjusted value)
appears in the bottom right corner of the display, while the
temperature value shown on the display switches from room
temperature to the default temperature (20.0°C) or to the last
set temperature (the set temperature is blinking on the display).
Pressing the buttons repeatedly or continuously (the change in
values is accelerated), the desired temperature to be maintained
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at the place where the thermostat has been installed can be set in
steps of 0.5°C.
Approximately 15 seconds after setting the room temperature to be•
maintained, the device automatically switches to normal mode. The
notice „Set” disappears from the bottom right corner of the display,
and once again the current room temperature is displayed.
6. OPERATION OF THE INSTALLEd THERMOSTAT
After connecting, commissioning and performing basic settings
and setting the temperature, the thermostat is ready
for operation and controls the connected devices
according to the position, i.e. HeAt or Defrosting
( ) of the operating mode switch located above
the push buttons for temperature adjustment.
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6.1 Heating Mode (right hand position of the switch)
According to the change in room temperature and temperature
setting, the device controls (switches on or off) the boiler or any other
heatingequipmentconnectedtotheappliance.Whenactivated,the
normally open contact pairs, i.e. No. 1(NO) and No. 2 (COM), of the
relay of the device clamp shut, and, as a consequence, the appliance
connected to the thermostat is switched on. The appearance of the
notice “HeAt” in the bottom left corner of the display indicates that
the device is activated.
6.2 Defrosting Mode (left hand position of the switch)
In the left hand position of the operating mode switch the
thermostat provides defrosting in the vicinity of the installation, and,
in order to avoid the possibility of freezing, it switches the boiler or
any other heating appliances connected to the thermostat on and off
below and above +7.0°C, respectively. During defrosting the normally
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open contact pairs, i.e. No. 1(NO) and No. 2(COM) of the relay of the
thermostat clamp shut and, as a consequence, the device connected
to the thermostat unit is switched on. The activated state is indicated
by the appearance of a (snowflake) icon on the LCD display.
During defrosting the temperature adjustment buttons are inactive.
7. BATTERY REPLACEMENT
The average lifetime of the batteries is 1 year. The “ ” icon
alternately replacing the temperature value on the LCD display
indicates low battery voltage. Replace the batteries whenever the
“ ” icon indicating low battery voltage appears on the display
(see Section 3). After battery replacement, the desired temperature
should be adjusted again, because during the battery replacement
the thermostat is reset to factory default settings.
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TECHNICAL dATA
— switchable voltage: 24 V AC / DC,…250 V AC; 50 Hz
— switchable current: 8 A (2 A inductive load)
— temperature measurement range: 5 to 35°C (in 0.1°C increments)
— adjustable temperature range: 10 to 30°C (in 0.5°C increments)
— temperature measurement accuracy: ±0.5°C
— selectable switching sensitivity: ±0.2°C / ±0.3°C
— defrosting temperature: +7°C
— storage temperature: -10°C to +60°C
— power supply voltage: 2x1.5 V AA alkaline batteries (LR6 type)
— power consumption: 1.5 mW
— battery lifetime: approx. 1 year
— dimensions: 110 x 75 x 45 mm
— weight: 154 g
— temperature sensor type: NTC 10 kΩ±1% at 25°C
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TheCOMPUTHERMQ3typethermostatcomplieswiththe
requirementsofstandardsEUEMC89/336/EEC;LVD73/23/
EEC;93/68/EECandR&TTE1999/5/EC.