Computherm Q4Z User manual

Operating Instructions
zone controller
(for controlling 1 to 4 heating zones)
COMPUTHERM Q4Z

- 3 -
1. GENERAL DESCRIPTION OF THE ZONE CONTROLLER
As the boilers usually have only one connection point for thermostats, a zone
controller is needed in order to divide the heating / cooling system into zones, to
control the zone valves and to control the boiler from more than one thermostat.
The zone controller receives switching signals from the thermostats (T1; T2;
T3; T4), controls the boiler (NO -COM) and gives commands to open/close the
heating zone valves (Z1; Z2; Z3; Z4, Z1-2; Z3-4; Z1-4) associated with the
thermostats.
The COMPUTHERM Q4Z zone controllers can control 1 to 4 heating / cooling
zones, which are regulated 1-4 switch-operated thermostats. The zones can
operate independently from each other or, in case of need, all zones can operate
at the same time.
To control more than 4 zones at a time we recommend using 2 or more
COMPUTHERM Q4Z zone controllers (1 zone controller needed per 4 zones). In
this case, the potential-free connection points controlling the boiler (NO - COM)
should be connected to the heater / cooler device in parallel.
The COMPUTHERM Q4Z zone controller provides the possibility for the
thermostats to also control a pump or a zone valve in addition to starting the
heater or cooler. This way it is easy to divide a heating / cooling system into
zones, thanks to which the heating / cooling of each room can be controlled se-
parately, thus greatly increasing comfort.
Furthermore, the zoning of the heating / cooling system will greatly contribute to
the reduction of energy costs, as due to this only those rooms will be heated /
cooled at any time where it is required.

- 4 -
An example of dividing the heating system into zones is shown in the gure
below:
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.
2. THE CONNECTION POINTS OF THE ZONE CONTROLLER,
MOST IMPORTANT TECHNICAL DATA
• Each of the 4 heating zones have an associated pair of connection
points (T1; T2; T3; T4); one for a room thermostat and one for a zone
valve/pump (Z1; Z2; Z3; Z4). The thermostat of the 1st zone (T1) controls
the zone valve/pump of the 1st zone (Z1), the thermostat of the 2nd zone
(T2) controls the zone valve/pump of the 2nd zone (Z2) etc. Following the
heating command of the thermostats, 230 V AC voltage appears on the
connection points of the zone valves associated with the thermostats,
and the zone valves/pumps connected to these connection points open/start.
For ease of use, the connection points associated with the same zone have
the same color (T1-Z1; T2-Z2, etc.).
living room bedroom 1 bedroom 2
230 V AC
boiler
distributor
manifold floor h. manifold
floor h. distributor
collector
oor heat. distr.
oor heat. collect.

- 5 -
• The 1st and 2nd zones, beside their regular connection points, also have
a joint connection point for a zone valve/pump (Z1-2). If any of the 1st two
thermostats (T1 and/or T2) switches on, then beside the 230 V AC voltage
appearing at Z1 and/or Z2, 230 V AC voltage appears on Z1-2 too, and the
zone valves/pumps connected to these connection points open/start. This Z1-2
connection point is suitable to control the zone valves/pumps in such rooms
(e.g. the hall or the bathroom), which do not have a separate thermostat, do not
need heating at all times but need heating when any of the 1st two zones heat.
• The 3rd and 4th zones, beside their regular connection points, also have
a joint connection point for a zone valve/pump (Z3-4). If any of the 2nd two
thermostats (T3 and/or T4) switches on, then beside the 230 V AC voltage
appearing at Z3 and/or Z4, 230 V AC voltage appears on Z3-4 too, and the
zone valves/pumps connected to these connection points open/start. This Z3-4
connection point is suitable to control the zone valves/pumps in such rooms
(e.g. the hall or the bathroom), which do not have a separate thermostat, do not
need heating at all times but need heating when any of the 2nd two zones heat.
• Moreover, the four heating zones also have a joint connection point
for a zone valve/pump (Z1-4). If any of the four thermostats (T1, T2, T3
and/or T4) switches on, then beside the 230 V AC voltage appearing
at Z1, Z2, Z3 and/or Z4, 230 V AC voltage appears on Z1-4 too, and the
pump connected to output Z1-4 also starts. This Z1-4 connection point is
suitable to control the heating in such rooms (e.g. the hall or the bathroom),
which do not have a separate thermostat, do not need heating at all times but
need heating when any of the four zones heat. This connection point is also
suitable for controlling a central circulating pump, which starts whenever any
of the heating zones starts.
• There are some zone valve actuators that need a x phase, a switched
phase and a neutral connection to operate. The connection points of the x
phase are next to the (POWER INPUT) indicated by the FL FL sign. The
connections of the x phase are only operating when the power switch is
turned on. Due to the lack of space there is only two connection points. By
joining the x phases four actuators can be operated.
• The 15 A fuse on the right side of the power switch protects the components
of the zone controller from electrical overload. In case of overloading the
fuse cuts o󰀨 the electric circuit, protecting the componets. If the fuse has cut
o󰀨 the circuit, check the appliances connected to the zone controller before

- 6 -
turning it on again, remove the broken components and the ones that cause
overloading, then replace the fuse.
• The 1st, 2nd, 3rd and 4th zones also have a joint potential-free connection
point that controls the boiler (NO -COM). These connection points clamp
shut following the heating command of any of the four thermostats, and this
starts the boiler.
• The NO - COM,Z1-2,Z3-4,Z1-4 outputs of the zone controller are equipped
with delay functions, see Section 5 for more information.
3. LOCATION OF THE DEVICE
It is reasonable to locate the zone controller near the boiler and/or the manifold
in a way, so that it is protected from dripping water, dusty and chemically
aggressive environment, extreme heat and mechanical damage.
4. INSTALLING THE ZONE CONTROLLER AND PUTTING IT
INTO OPERATION
Attention! The device must be installed and connected by a qualied
professional! Before putting the zone controller into operation make sure that
neither the zone controller nor the apparatus to be connected to it is connected
to the 230 V mains voltage. Modifying the device can cause electric shock or
product failure.
Attention! We recommend that you design the heating system you want to
control with the COMPUTHERM Q4Z zone controller so that the heating medium
can circulate in the closed position of all zone valves when a circulating pump
is switched on. This can be done with a permanently open heating circuit or by
installing a by-pass valve.
Attention! In switched on state 230 V AC voltage appears on the zone outputs,
the maximum loadability is 2 A (0,5 A inductive). This information should be
considered at the installation.
The size of the connection points of the COMPUTHERM Q4Z zone controller
allow at most 2 or 3 devices to be connected in parallel to any heating zone.
If more than this is needed for any of the heating zones (e.g. 4 zone valves),
then the wires of the devices should be joined before they are connected to the
zone controller.
To install the zone controller, follow these steps:
• Detach the rear panel of the device from its front panel by loosening the
screws at the bottom of the cover. By this, the connection points of the

- 7 -
thermostats, the zone valves/pumps, the boiler and the power supply are
accessible.
• Select the location of the zone controller near the boiler and/or the manifold
and create the holes on the wall for installation.
• Secure the zone controller board to the wall using the supplied screws.
• Connect the wires of the needed heating equipment (the wires of the
thermostats, the zone valves/pumps and the boiler) and the wires for
power supply as shown in the gure below.
• Replace the front cover of the device and secure it with the screws at the
bottom of the cover.
• Connect the zone controller to the 230 V mains network.
connection points of the thermostats connection points for power supply
x phase
(working when
the power switch
is turned on)
fuse (15 A)
connection points controlling the boiler connection points of the heating zones
In case of using electro-thermal zone valves that operate slowly and all the
zones are closed when the boiler is inactive, then the boiler should be started
with a delay in order to protect the pump of the boiler. In case of using electro-
thermal zone valves that operate fast and all the zones are closed when the
boiler is inactive, then the valves should close with a delay in order to protect the
pump of the boiler. See Section 5 for more information on the delay funcions.
5. DELAY OF THE OUTPUTS
When designing the heating zones - in order to protect the pumps - it is advisable
to keep at least one heating circuit that is not closed by a zone valve (e.g. bathroom

- 8 -
circuit). If there are no such zones, then in order to prevent the heating system
from an event in which all heating circuits are closed but a pump is switched on,
the zone controller has two types of delay function.
5.1 Turn on delay
If this function is activated and the outputs of the thermostats are switched o󰀨,
then in order to open the valves of the given heating circuit before starting the
pump(s), the zone controller NO-COM and Z1-4 output, and depending on the
zone the Z1-2 or Z3-4 output switches on only after a delay of 4 minutes from the
1st switch-on signal of the thermostats, while 230 V appears immediately at the
output for that zone (eg. Z2). The delay is especially recommended if the zone
valves are opened/closed by slow-acting electrothermal actuators, because their
opening/closing time is approx. 4 min. If at least 1 zone is already switched on,
then the Turn on delay function will not be activated when additional thermostats
switch on.
The active state of the Turn on delay function is indicated by the blue LED ashing
with 3-second intervals.
If the “A/M” button is pressed while the Turn on delay is active (blue LED ashes
with 3-second intervals), the LED stops ashing and indicates the current
operating mode (Automatic/Manual). Then the working mode can be changed
by pressing the “A/M” button again. After 10 seconds, the blue LED continues to
ash with 3-second intervals until the delay stops.
5.2 Turn o󰀨 delay
If this function is activated and some thermostat outputs of zone controller are
switched on, then in order for the valves belonging to the given zone to be
open during the recirculation of the pump(s), the 230 V AC voltage disappears
from the zone output of the given zone (eg Z2), output Z1-4 and, depending
on the switched zone, output Z1-2 or Z3-4 only after a delay of 6 minutes from
the switch-o󰀨 signal of the last thermostat, while the NO-COM output switches
o󰀨 immediately. The delay is especially recommended if the zone valves are
opened/closed by quick-acting motorized actuators, as their opening/closing
time is only a few seconds. Activating the function in this case ensures that the
heating circuits are open during the circulation of the pump and thus protects
the pump from overload. This function is only activated when the last thermostat
sends the switch-o󰀨 signal to the zone controller.
The active state of the Turn o󰀨 delay function is indicated by the 3-second
interval ashing of the red LED of the last zone switched o󰀨.

- 9 -
5.3 Activating/deactivating of the delay functions
To activate/deactivate the Turn on and o󰀨 delay functions, press and hold the
Z1 and Z2 buttons on the zone controller for 5 seconds until the blue LED
ashes at one second intervals. You can activate/deactivate the functions by
pressing the buttons Z1 and Z2. The LED Z1 shows the Turn on delay status,
while the LED Z2 shows the Turn o󰀨 delay status. The function is activated
when the corresponding red LED is lit.
To save the settings and return to the default state wait 10 seconds. When the
blue LED stops ashing the zone controller resumes the normal operation.
The delay functions can be reset to the factory defaults (deactivated state) by
pressing the “RESET” button!
6. USING THE ZONE CONTROLLER
After installing the device, putting it into operation and turning it on with its switch
(position ON), it is ready for operation, which is indicated by the illuminated
state of the red LED with sign “POWER” and the blue LED with sign “A/M” on
the front panel. Then, following the heating command of any of the thermostats,
the zone valves/pumps associated with the thermostat open/start and the boiler
also starts, also taking the Turn on delay function into account (see Section 5).
By pressing the “A/M” (AUTO/MANUAL) button (the factory default AUTO sta-
tus is indicated by the illumination of the blue LED next to the “A/M” button) it
is possible to detach the thermostats and manually adjust the heating zones
for each thermostat to start. This may be necessary temporarily if, for exam-
ple, one of the thermostats has failed or the battery in one of the thermostats
has run down. After pressing the “A/M” button, the heating of each zone can
be started manually by pressing the button indicating the zone number. The
operation of the zones activated by manual control is also indicated by the
red LED of the zones, but in manual control the blue LED indicating the “A/M”
status is not illuminated. (In case of manual control, the heating of the zones
operates without temperature control.) From manual control, you can return
to the thermostat-controlled factory default operation (AUTO) by pressing the
“A/M” button again.
Warning! The manufacturer does not assume responsibility for any direct
or indirect damages and loss of income occurring while the appliance is
being used.

TECHNICAL DATA
‒ Supply voltage: 230 V AC, 50 Hz
‒ Standby power consumption: 0,15 W
‒ Voltage of the zone outputs: 230 V AC, 50 Hz
‒ Loadability of the zone outputs: 2 A (0.5 A inductive load)
‒ Switchable voltage of the
relay that controls the boiler: 230 V AC, 50 Hz
‒ Switchable current of the relay
that controls the boiler: 8 A (2 A inductive load)
‒ Duration of activable Turn on
delay function: 4 minutes
‒ Duration of activable Turn off
delay function: 6 minutes
‒ Storage temperature: -10 °C - + 40 °C
‒ Operating humidity: 5% - 90% (without condensation)
‒ Protection against
environmental impacts: IP30