Quantrax COMPUTHERM Q8RF User manual

COMPUTHERM Q8RF (TX)
Wireless (radio frequency) programmable
digital room thermostat (without receiver)
Operating Instructions
You can watch the most important aspects of the usage of this thermostat
on our video presentation at www.computherm.info

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GENERAL DESCRIPTION OF THE THERMOSTAT
The COMPUTHERM Q8RF (TX) type switched-mode room thermostat is suitable to
regulate the overwhelming majority of boilers and air conditioners. It can be used together
with the COMPUTHERM Q5RF and Q8RF multi-zone thermostats to complement the two
thermostats in the basic package, to increase the number of zones regulated and to
control the COMPUTHERM Q1RX wireless (radio-frequency) thermostat-controlled socket.
You can nd detailed information and recommended usage of the COMPUTHERM
Q1RX socket and COMPUTHERM Q5RF and Q8RF multizone thermostats on our
website: www.computherm.info.
Because there is a wireless (radio-frequency) connection between the COMPUTHERM
Q8RF (TX) thermostat and the receiver unit of the COMPUTHERM Q5RF/Q8RF thermostat
and/or the COMPUTHERM Q1RX socket, no cable is required between the thermostat and
the receiver and/or the socket.
The device can be programmed according to customer-specic requirements so that
the heating/cooling system heats/cools your residence or o󰀩ce to the required temperature
at the times specied by the customer, to reduce energy costs while maintaining comfort.
Separate temperature programs can be prepared for each day of the week. For each
day, beside 1 xed switching time (PROG ), 6 adjustable switching times (PROG ‒
PROG ) can be set (at 10-minute intervals) and di󰀨erent temperature (in 0.5 °C
increments) can be assigned to all switching times.

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To increase the lifetime of the batteries, the thermostat will not transmit signals continuously.
Instead it will repeatedly transmit the actual signal every 8 minutes. Therefore, the
regulation of the heating or cooling will continue even after a blackout.
The portability of the thermostat o󰀨ers the following advantages:
• no need to lay a cable, which is especially advantageous when old buildings are being
modernized,
• the optimal location of the device can be selected during operation.
Thermostat
Boiler
Reciever
230 V AC, 50 Hz
Zone valves 230 V AC, 50 Hz

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The e󰀨ective range of the transmitter incorporated in the thermostat is approximately
50 m in open terrain. This distance may become considerably shorter within a building,
especially when a metal structure, reinforced concrete or adobe wall stands in the way of
radio waves.
The information shown on the liquid crystal display of the thermostat includes
the following:
The days of the week
Manual control
indicator
Current temperature
of the room
Set temperature
Low battery voltage
Sign of the boiler/air
conditioner
working
Time
Program number
Temperature
modication until
the next manual
interference
Timed manual control
indication

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1. LOCATION OF THE DEVICE
The thermostats of the COMPUTHERM Q8RF (TX) multi-zone programmable wireless type
device can be freely moved in your residence. It is reasonable to locate them in rooms used
regularly or for many hours per day so that they are in the direction of natural ventilation in the
room but protected from drought or extreme heat (e.g. direct sunlight, refrigerator, chimney,
etc). Do not use in wet, chemically aggressive or dusty environment. Their optimal location is
0.75 - 1.5 m above oor level. They can be placed on their own stand or can be mounted
on a wall.
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 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. PUTTING THE THERMOSTAT INTO OPERATION, BASIC
SETTINGS
Warning! The device must be installed and connected by a qualied professional.
2.1 Inserting batteries
Pressing the lock on the upper side of the housing of the thermostat, remove the back
cover of the thermostat as shown in the gure below.

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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.
Warning! Good quality alkaline batteries may only be
used for this appliance. Carbon-zinc batteries known as
durable or long life batteries and chargeable accumulators
are not suitable for the operation of this appliance. Icon
appearing on the display to indicate low battery voltage
warns reliably that the batteries should be replaced only
when good quality alkaline are used.
After the batteries have been inserted, the display ashes the day, time and program
number as well as the adjusted and measured temperatures. (If this information fails
to appear on the display, press the “RESET” button located on the main panel of the
thermostat. After the batteries have been inserted, snap the front panel of the device into
the rear panel and press the “SET” button. After the “SET” button is pressed, the display
stops ashing, the thermostat goes to the main screen and the setting process can be
started.
2.2 Setting the current day and time
Press the “SET” button to go to the main screen, then press the “DAY” button. At this time
only the 1st three letters of the current day will ash on the display of the thermostat and
the hour and minute values can be seen.

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Using the large and buttons on the front panel of the device, set the the cur-
rent day (Monday MON; Tuesday TUE; Wednesday WED, etc.). Press the “DAY” button
again. At this time the contraction indicating the day stops ashing and becomes visible
continuously while the abbreviation indicating the hour will ash on the display. Using
the large and buttons on the front panel of the device, set the hour value
of the current time. Press the “DAY” button again. At this time the numbers that indicate
the hour stop ashing and become visible continuously, while the numbers indicating the
minute will begin ashing. Using the large and buttons on the front panel of
the device, set the minute value of the current time.
When you wish to continue modifying the settings, please press the “DAY” button again.
If you wish to nish settings, conrm them by pressing the “SET” button. At this point
adjusted data are recorded and the device goes back to the main screen (if no buttons
are pressed for at least 15 seconds, the settings are automatically conrmed and the
device goes back to the main screen).
2.3 Switching between the heating and cooling mode
There is a possibility to easily switch between the heating and cooling mode of the
thermostat. The output terminals of the receiver unit NO - COM and the zone outputs are
turned on below the set temperature in heating mode and above the set temperature in
cooling mode. (Taking the switching sensitivity into account).

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To switch between the two modes, 1st press the “SET” button to go to the main screen.
Then press the “SET” button again and hold it down and press the “COPY” button, too.
After this, the notice “ ” or “ ” appears in place of the time characters, according to
the selected mode. Following this, switch between the modes using the large and
buttons, then conrm it by pressing the “SET” button (if no buttons are pressed for
at least 15 seconds, the setting is automatically conrmed). After this conrmation, the
device goes back to the main screen.
2.4 Setting the switching sensitivity (accuracy)
There is a possibility to change the switching sensitivity. The switching sensitivity means
the temperature di󰀨erence between the adjusted value and the actual temperature
measured during the switching process.
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 o󰀨 multiple times in an hour's time except at low outside
temperatures (e.g. -10 °C), since the frequent on and o󰀨 switches of the boiler reduce its
e󰀩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),
the ±0.2 °C (factory default setting) and ±0.3 °C switching sensitivity for heating systems
with low thermal inertia (e.g. at panel radiators).

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To change the switching sensitivity, 1st press the “SET” button to go to the main screen.
Then press the “DAY” and “COPY” buttons one after the other. Following this, select
the desired switching sensitivity using the large and buttons. The notices
“ ”, “ ” and “ ” indicate ±0.1 °C, ±0.2 °C and ±0.3 °C, respectively. Finally, conrm
the setting by pressing the “SET” button (if no buttons are pressed for at least 15 seconds,
the setting is automatically conrmed). After this conrmation, the device goes back to the
main screen. You can read more about switching sensitivity in Section 3.
2.5 Activation of the pump protection function
According to the factory default settings, the pump protection function is inactive. In order
to activate or deactivate it, 1st press the “SET” button to go to the main screen. Then press
the “DAY” and “PROG” buttons one after the other. Following this, activate or deactivate
this function by using the large and buttons. The notices “ ” and
“ ” indicate activated and deactivated state, respectively.
Finally, conrm the setting by pressing the “SET” button (if no buttons are pressed for
at least 15 seconds, the setting is automatically conrmed). After this conrmation, the
device goes back to the main screen.
To prevent the pump from sticking, the activated pump protection function switches on the
connected device for one minute period at 12:00 p.m. every day, if no switching has taken
place on the given day or the previous day (e.g. during the heating-free period).

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The pump protection function can accomplish its task only if the boiler is in working order
in the summer, too. It is reasonable to set a low temperature level, e.g. +10°C, on the
thermostat for this period, to prevent the boiler from unnecessary start-ups when the
weather turns cold temporarily.
2.6 Calibrating the thermometer of the thermostat
There is a possibility to calibrate the thermometer of the thermostat (to correct the
measured temperature). In order to do this, 1st press the “SET” button to go to the main
screen. Then press the “DAY” and “HOLD” buttons one after the other. After this, the notice
“” appears in place of the time characters, and the correction value appears in
place of the measured temperature ( °C by default). Following this, set the desired
correction value using the large and buttons between -3.0 °C and +3.0 °C, in
0.1 °C increments. Finally, conrm the setting by pressing the “SET” button (if no buttons
are pressed for at least 15 seconds, the setting is automatically conrmed). After this
conrmation, the device goes back to the main screen. The correction of the measured
temperature takes e󰀨ect a couple of seconds after the conrmation.
3. OPERATION OF THE INSTALLED THERMOSTAT
The thermostat controls the device connected to it (e.g. gas boiler or pump) based on
the temperature measured by it and the currently set temperature, taking into account
the switching sensitivity of the thermostat (factory default ±0.2 °C). This means that if the
thermostat is set to heating mode and 22 °C, then with a switching sensitivity of ±0.2 °C

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the connection points NO and COM of the receiver output relay are closed at temperatures
below 21.8 °C (heating is turned on) and 230 V AC is displayed on the output for that zone.
The NO and COM conection points are opened at temperatures above 22.2 °C (heating
is turned o󰀨) and the 230 V AC voltage at its output for that zone is turned o󰀨. In cooling
mode, the relays switch exactly the opposite way.
The closed status of the output relay terminals NO and COM is indicated by the or
icon in the lower left corner of the display, depending on the selected operating mode.
4. PROGRAMMING THE THERMOSTAT
4.1 A brief introduction to programming
• Programming means the setting of switching times and selection of accompanying
temperature levels. The device can be programmed for a one-week period. Its operation
is automatic, and it will cyclically repeat the programs that have been keyed in. For
each day, beside 1 xed (PROG ) switching time, 6 adjustable (PROG ‒ PROG
) switching times can be set. For all switching times a di󰀨erent temperature can
be assigned between 5 and 40 °C, in 0.5 °C increments. The temperature set for a
given switch will remain valid until the start time of the next switch. Accordingly, the
thermostat will keep the temperature set for switching time PROG until switching time
PROG is reached. After switching time PROG the temperature selected to switch
PROG will be valid until the time of the next switch (PROG ).

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• The start time of switch PROG is , which cannot be changed, only its temperature
can be adjusted. So under the factory default settings, the thermostat performs only one
switch (PROG ) every day, which is in e󰀨ect from until the next day.
Note: Setting just one switch for a day (factory default setting) is reasonable only if a
constant temperature is needed all day. (For example, if for every weekday a constant
16 °C, and for every weekend a constant 22 °C is needed.) Otherwise, from both a
comfort and an energy-e󰀩ciency point of view, it is recommended to activate more than
one switch for each day. Furthermore, it is advised that a comfort temperature is used
only those times, when the room or building is in use, since every 1 °C decrease of
temperature saves approximately 6% energy during a heating season.
• The PROG ‒ PROG switches are deactivated by factory default (their start time is
), but they can be activated at need. Their start time can be freely set between
and at 10-minute intervals given the constraint, that their start time
should be in increasing order and a di󰀨erence of at least 10 minutes should be between
them. This minimum 10-minute di󰀨erence is going to be preserved even if a previously
activated switch is modied, in order to avoid co-occurring or overlapping switches. In
such a case, the device automatically increases the start time of the a󰀨ected switches
until a di󰀨erence of at least 10 minutes between them is reached. If the start time of
a switch would be later than because of this automatic modication, then that
switch is deactivated instead.
• In order to enter the programming mode, press the “SET” button and hold it down and
press the “PROG” button, too. During the programming the values being adjusted

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are ashing on the display. The modication of these values can always be done
using the large and buttons. The conrmation of a value is always
done by pressing the “PROG” button, after which the next value can be adjusted. The
program can be saved by pressing the “SET” button. A more detailed description of the
programming steps can be found in Section 4.3.
• If there are days, for which the same program is needed, than it is su󰀩cient to create that
program only once, since it can be easily copied to another day using the “COPY” button
as described in Section 4.4. If the same program is needed for every day, then there is
also a possibility to create the program of all the days together (by selecting MON TUE
WED THU FRI SAT SUN together during the selection of days). But be aware: if the
program of all the days are created together, than their program can only be modied
together. Therefore, if a di󰀨erent program is needed for at least one day, then the program
of the days should be created separately, and the repeated programs should be copied
using the “COPY” button.
• A separate program can be created for the heating and cooling mode, and these
programs are preserved when switching between the modes. Therefore, if the thermostat
is used for both heating and cooling, then there is no need to modify the program of the
thermostat every time a switch between these modes is performed.
4.2 Recommendations for creating a heating program
The average comfort needs of a person can usually be satised by a temperature of 19-
21 °C during the night, and a temperature of 22-23 °C during the day. During that time

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of the day, when the family is at work or school, only a lower temperature is needed. As
heating up and cooling down usually takes a long time, it is reasonable to set the start
time of the switches 0.5-1 hour before the desired time of the modied temperature. The
programmability of the thermostat provides a perfect solution for this.
For an average working family, a program similar to the one below is recommended:
4.3 Programming steps
a. Press the “SET” button to go to the main screen.
b. Press the “SET” button again and hold it down and press the “PROG” button, too. At
this point the device gets into programming mode and the abbreviations indicating the
days of the week (MON TUE WED THU FRI SAT SUN) are ashing on the display.
c. Select the day to be programmed using the large and buttons on the
front panel of the device (MON indicating Monday, TUE indicating Tuesday etc.). If
you wish to create the same program for each day of the week, it is reasonable to

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choose all days of the week simultaneously (by selecting MON TUE WED THU FRI
SAT SUN together), this way there is no need to perform separate programming of
the days. After selecting the desired day(s), press the “PROG” button.
d. At this point the temperature of switch PROG should be set, which is indicated
on the display of the device by ashing the temperature value to be set ( °C by
default). Set the desired temperature using the large and buttons, then
press the “PROG” button.
e. Then, the start time of switch PROG should be adjusted, which is indicated on
the display of the device by ashing the time value to be adjusted ( by default).
Set the desired time using the large and buttons, then press the “PROG”
button.
f. Following this, the temperature of switch PROG should be set, which is indicated
on the display of the device by ashing the temperature value to be set ( °C by
default). Set this temperature level of switch PROG using the large and
buttons, then press the “PROG” button.
g. The next step in programming is the adjustment of the start time of switch PROG ,
which is indicated on the display of the device by ashing the time value to be adjusted
(by default). The adjustment process of switches PROG ‒ PROG can be
done (the same way as switch PROG is adjusted) by repeating the “e”-“f ” steps.
If you do not want to activate any more switches for the selected day(s), then press
the “PROG” button without changing the start time of the next switch from the default

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. This way the programming of the selected day(s) is nished, the thermostat
o󰀨ers another day to be programmed and the programming can be continued from
step “c ”.
If all the switches (PROG ‒ PROG ) are activated for the selected day(s), then after
setting the temperature value of PROG , the programming of the selected day(s) is
nished, the thermostat o󰀨ers another day to be programmed and the programming
can be continued from step “c ”.
h. The adjusted program can be saved by pressing the “SET”button. After
approximately 1 minute, the adjusted program is automatically saved. Afterwards, the
device goes back to the main screen.
If you wish to copy the program of the day(s) selected in step “c ” to other days, you can
easily do so using the “COPY” button as described in Section 4.4.
4.4 Using the “COPY” function (Copying the program of a day to other days)
• 1st, press the “SET” button to go to the main screen. Then press the “COPY”
button for approximately 3 seconds to activate the “COPY” function. The notice
“ ” appearing in place of the time characters and the ashing abbreviation MON
indicating Monday shows that conditions are ready for copying a program.
• Select the day whose program you wish to copy to another day or other days using
the large and buttons on the front panel of the device.

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• Press the “COPY” button to copy the program of the selected day. After this, the
ashing of the abbreviation indicating the day that has been copied stops and it will
be visible continuously hereafter.
• Select the day to which you wish to copy the program of the day copied beforehand
using the large and buttons. The abbreviation of the active day is ashing
during this selection process.
• After selecting the abbreviation that indicates the day to which you wish to copy the
program, press the “COPY” button to copy the program. Hereafter, the abbreviation
indicating the day to which the program was copied will be visible continuously.
Following this, you can select further days using the large and buttons
and copy the program to those days too by pressing the “COPY” button.
• Finally, press the “SET” button to save the modications (if no buttons are pressed
for at least 15 seconds, the modications will be automatically saved). Afterwards, the
device goes back to the main screen. If required, the program of further days can be
freely copied by repeating the above steps.
ATTENTION! The “COPY” function is only available, if the days of the week were
programmed separately!
4.5 Modifying the program
• The previously set program can be modied any time by repeating the steps of
programming.

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• The number of activated switches can be increased at will as described in Section
4.3.
• A previously activated switch can be deactivated by setting its start time to using
the large and buttons (or by pressing the “DAY” button once), and then
pressing the “PROG” button. After this, if the deactivated switch was an intermediate
one, then the serial numbers of the remaining switches will be updated.
• If you wish to nish modifying the program of the selected day, then press the “PROG”
button and hold it down for at least 3 seconds. After this, the modication can be
continued by selecting another day. When nished with all the modications, press
the “SET” button to save them. After approximately 1 minute, they are automatically
saved. Afterwards, the device goes back to the main screen.
• If a completely di󰀨erent program is needed, then press the “RESET” button located on
the main panel of the thermostat to reset the device (it deletes both the program and
the basic settings). Following this, adjust the basic settings of the thermostat again
and create the new program, as described in Sections 2and 4.
4.6 Program inspection
• 1st, press the “SET” button to go to the main screen, then press the “PROG” button.
At this point, the abbreviation indicating the day(s), the symbol of switch PROG
and the time and temperature level set for switch PROG of the selected day(s) will
appear on the display (none of the values is ashing).

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• Repeatedly press the “PROG” button to check the values of switch PROG , PROG
, etc. Use the large and buttons to change the day(s). If all the days
were programmed together (MON TUE WED THU FRI SAT SUN), then their common
program can only be viewed together.
• After checking the program, press the “SET” button to go back to the main screen (if
no buttons are pressed for at least 15 seconds, the thermostat will automatically go
back to the main screen).
5. TEMPORARY MODIFICATION OF THE TEMPERATURE
CORRESPONDING TO THE PROGRAM
If you wish to operate your device in a way that di󰀨ers temporarily from the program that
has been set (e.g. on bank holidays or the winter holidays), you can choose among the
options described in Sections 5.1- 5.4.
To simplify manual temperature modications, with factory default settings temperatures
of °C and °C are assigned to the large and buttons, respectively. When
modifying the temperature manually, pressing the and button once, the
temperature will immediately jump to the factory value of the button. For example, if the
current switch PROG ensures a temperature of °C, it can be modied to a standard
temperature that ensures °C when needed by pressing the button only once,
without having to press the button several times in increments of 0.5 °C. Following
this, using the large and buttons, the temperature can be further modied in
increments of 0.5 °C, in accordance with current requirements.

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The economy and comfort temperature values assigned to buttons and can
be modied as follows:
• To set the economy temperature, press the “SET” button and keep it depressed and
press the button, too. Following this, with the help of the and buttons,
set the economy temperature selected by you. After the temperature has been set,
press the “SET” button to save the modication (after approximately 15 seconds, it is
automatically saved). Afterwards, the device goes back to the main screen.
• To set the comfort temperature, press the “SET” button and keep it depressed and
press the button, too. Following this, with the help of the and buttons,
set the comfort temperature selected by you. After the temperature has been set,
press the “SET” button to save the modication (after approximately 15 seconds, it is
automatically saved). Afterwards, the device goes back to the main screen.
5.1 Temperature modication until the next program switch
Set the required temperature using the large and buttons on the front panel
of the device. After the temperature modication the program number disappears, and the
icon appears on the display, indicating that the thermostat is operated with manual
control. The device will control the boiler according to the set value until the time of the
next switch specied in the program is reached.
During this temporary modication, the segments indicating the time on the display
alternately show the exact time (TIME) and the time remaining (TIME LEFT) in manual