Computherm Q3 User manual

COMPUTHERM Q3
digital room thermostat
Operating Instructions
NEW
software!
For Evaluation Only.
Copyright (c) by Foxit Software Company, 2004
Edited by Foxit PDF Editor

GENERAL DESCRIPTION OF THE THERMOSTAT
The COMPUTHERM Q3 type switched-mode room thermostat
is suitable to regulate the overwhelming majority of boilers and
air conditioners 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 24V
or 230V control circuit.
Temperature can be measured and set more precisely as compared
to simple, conventional thermostats. In heating mode, in accordance
with the selected switching sensitivity, the thermostat switches 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. In cooling mode it switches the opposite way.
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The switching sensitivity of the thermostat can be set to ±0.1°C or
±0.2°C (default setting). This means the difference between the ad-
justed temperature
and the actual tem-
peraturemeasured
during the switch-
ing process. In
case of the ±0.2°C
switching sensi-
tivity and heating
mode for example,
if the set tempera-
ture is 20°C, then
the device switch-
Temperature
Temperature
measurement unit
Room temperature
is displayed
Set temperature
is displayed
Sign of heating
Sign of cooling
The information shown on the liquid crystal
display of the thermostat
includes the following:
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es the boiler on at 19.8°C or below, and switches it off at 20.2°C or
above. Please refer to Section 4.1 for the modication of the factory
default switching sensitivity of ±0.2°C.
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 oor
level.
IMPORTANT WARNING!
If the radiator valves in your at are equipped with a thermostatic head,
adjust it to maximum temperature or replace the thermostatic head of
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the radiator valve with a manual control knob in the room where the
room thermostat is to be located, otherwise the thermostatic head
may disturb the temperature control of the at.
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
gure.
With the help of the screws provided and
• some tools fasten the rear panel of the
device to the wall.
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Using a small screwdriver, remove the cover of the• terminal block from the inner side of the rear panel.
The thermostat controls the boiler or air conditioner
through a potential-free alternating relay that has the
following connection points: No. 1 (NO); No. 2 (COM)
and No. 3 (NC). These connection points are located
under an inner cover on the inner side of the rear
panel.
Connectthetwoconnectionpointsoftheheatingorcoolingequipment
• to be controlled to terminals No. 1 (NO) and No. 2 (COM), i.e. to the
normally open terminals of the relay. If you would like to operate
an old boiler or any other device that has no connection points for
thermostats, then the No. 1 (NO) and No. 2 (COM) connection points
of the thermostat should be connected to the mains cable of the
device, similarly as a switch would be connected.
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To prevent electric shock, replace the inner cover removed
for the connection of wires after the assembling process
has been completed.
ATTENTION! Always consider the loadability of the thermostat
and follow the manufacturer’s instructions of the heating or cooling
equipment. The device must be installed and connected by a
qualied professional. The voltage appearing at terminals No. 1 and
No. 2 depends 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 signicance.
3. PUTTING THE THERMOSTAT INTO OPERATION
The battery compartment is in the inner side of the front panel of the
housing. Insert 2 AA alkaline batteries (LR6 type) in accordance
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withthediagraminthebatterycompartment.Afterthebatterieshave
been inserted, the display ashes 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, e.g. graphite pencil).
4. BASIC SETTINGS
After removing the rear panel of
the device, the following factory
default settings can be modied
by relocating the jumpers (black
plugs) located on the base
panel.
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4.1 Selecting the Switching Sensitivity (Accuracy)
The switching sensitivity of the thermostat can be selected or
adjusted by the uppermost jumper.
With factory default settings the jumper is located on the central
and right pins, resulting in a switching sensitivity of ±0.2°C. It can
be modied to ±0.1°C by relocating the jumper onto the left and
central pins. A smaller switching sensitivity results in steadier room
temperature and therefore in higher comfort. The heat loss of the
room (building) does not depend on the switching sensitivity.
If higher comfort is needed, the switching sensitivity should be
set so that it provides a steadier room temperature. On the other
hand, please also take into account that the boiler should not
switch on and off multiple times in an hour’s time except at low
outside temperatures (e.g. -10°C), since the frequent on and off
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switches of the boiler reduce its efciency and hence increases
the gas consumption. We recommend using the ±0.1°C switching
sensitivity for heating systems with high thermal inertia (e.g.
underoor heating), and the ±0.2°C switching sensitivity (factory
default setting) for heating systems with low thermal inertia (e.g.
at panel radiators).
4.2 Switching between the Heating and Cooling Mode
The heating or the cooling mode of the thermostat can be selected
by the central jumper.
With factory default settings the jumper is located on the central
and right pins, which selects the heating mode. By relocating the
jumper onto the left and central pins, the cooling mode can be
selected. The output terminals No. 1 and No. 2 of the thermostat
are closed below the set temperature in heating mode, and they
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are closed above the set temperature in cooling mode (taking the
switching sensitivity into account). The closed state of the output
terminals No. 1 and No. 2 are indicated by the notice “HEAT”
(heating) or “A/C” (cooling) in the bottom left corner of the display,
according to the selected mode.
4.3 Selecting the Displayed Temperature
The temperature(s) to be shown on the display can be selected and set
by the bottommost jumper.
With factory default settings the jumper is located on the central and
right pins, in which case the display shows the currently measured room
temperature value, while the notice “ROOM” appearsinthebottomright
corner of the display. In this case, the adjusted temperature is visible
only during the adjustment process, for approximately 7 seconds after
the last button has been pushed. By relocating the plug onto the left
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and central pins the displayed temperature can be modied so that the
displayalternatelyshowsthecurrentroom temperatureandtheadjusted
temperature for 4 seconds, respectively. In this mode, the 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! If the modication of the basic settings was done
after inserting the batteries and the modications did not take
effect, please press the “RESET” button with a small wooden or
plastic stick to activate them. To press the button, do not use any
electrically conductive materials (e.g. graphite pencil).
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5. SETTING THE DESIRED TEMPERATURE
After putting the thermostat into operation and adjusting the basic
settings the thermostat is ready for operation and the adjustment of
the temperature can be started.
Above the temperature adjustment buttons (
and )aswitch islocated.Forboththeeconomy
(w
)and the comfort (☼) positions of the switch
a different temperature can be set between 5°C
and 35°C, in steps of 0.5°C.
For energy efciency it is recommended that the comfort temperature
is only used those times, when the room or building is in use,
because every 1°C decrease of temperature saves approximately
6% energy during a heating season. As opposed to common belief,
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keeping a at warn requires more energy than heating it up. (When
using a stove, more gas is needed to keep a pan of water boiling than
to just keep it warm.)
The factory default temperature is 18°C for the economy position and
20°C for the comfort position. These default temperatures can be
changed as follows:
Move the switch according to the temperature you would like to
• change (economy (w
) or comfort (☼)).
Press the
• or button, after which the notice “ROOM”
disappears, the notice “SET” (adjusted value) appears in the
bottom right corner of the display. Meanwhile, the temperature
value shown on the display switches from room temperature to the
default temperature (18.0°C/20.0°C) or to the last set temperature
(thistemperatureisblinkingonthedisplay).Bypressingthebuttons
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repeatedly or continuously (the change in values is accelerated),
the desired temperature to be maintained at the place where the
thermostat has been installed can be set in steps of 0.5°C.
Approximately 7 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 and the
notice “ROOM” are displayed.
The previously set temperature can be freely changed any time
• using the and buttons. Always the last set temperatures are
in effect.
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6. OPERATION OF THE INSTALLED THERMOSTAT
After setting the economy and comfort temperatures, the
temperature needed at the moment can be selected using the
switch.
6.1 Economy Mode (w
) (left hand position of the switch)
In the left hand position of the switch, the thermostat provides the
set economy temperature (e.g. night temperature) to be maintained
at the place where the thermostat has been installed. According
to the change in room temperature and temperature setting, the
thermostat controls (switches on or off) the boiler or any other
equipment connected to it. When activated, the normally 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 appliance
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connected to the thermostat is switched on. The appearance of the
notice “HEAT” (heating) or “A/C” (cooling) in the bottom left corner
of the display indicates that the device is activated, according to the
heating or cooling mode, respectively.
6.2 Comfort Mode (☼) (right hand position of the switch)
In the right hand position of the switch, the thermostat provides
the set comfort temperature (e.g. daytime temperature) to be
maintained at the place where the thermostat has been installed.
According to the change in room temperature and temperature
setting, the thermostat controls (switches on or off) the boiler or
any other equipment connected to it. When activated, the normally
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 appliance
connected to the thermostat is switched on. The appearance of the
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notice “HEAT” (heating) or “A/C” (cooling) in the bottom left corner
of the display indicates that the device is activated, according to the
heating or cooling mode, respectively.
7. BATTERY REPLACEMENT
The average lifetime of the batteries is 1 year. The icon
alternately replacing the temperature value on the 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: 24V AC/DC to 250V AC, 50 Hz
— switchable current: 8A (2A inductive load)
— temperature measurement range: 5 to 35°C (in 0.1°C increments)
— adjustable temperature range: 5 to 35°C (in 0.5°C increments)
— temperature measurement accuracy: ±0.5°C
— selectable switching sensitivity: ±0.1°C; ±0.2°C
— storage temperature: -10°C to +40°C
— battery voltage: 2 x 1.5V ALKALINE batteries
(LR6 type; AA size)
— power consumption: 1.5mW
— battery lifetime: approx. 1 year
— dimensions: 112 x 75 x 45mm
— weight: 154g
— temperature sensor type: NTC 10kΩ±1% at 25°C
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