3.6 Alarm
Signals from the room thermostats are transmitted at intervals
of 2-30 minutes. If the base unit has not received a signal from
any of the registered thermostats in 2-3 hours, the alarm func-
tion is activated. The LED for the relevant channel will start to
ash. Whilst a channel is in the alarm condition the actuator
output will be continuously activated for seven minutes and
closed for 14 minutes.
Where the alarm switch is in the ON position in the base
unit (see Fig 10 and 4.2 Installation and wiring of the base
unit), an acoustic signal (buzzer) will also start to sound after
a further 8 hours if the base unit has still not received a signal.
The acoustic alarm is switched off by pressing any button on
the base unit.
Once the base unit receives a signal again, the visual and audible
alarms will stop. Alternatively interrupting the current to the
base unit will shut off all the alarm functions.
Check the following when an alarm is triggered:
1. Remove the thermostat from the wall
2. Remove the dial and loosen the front of the thermostat by
gently pringing off the bottom of the thermostat.
3. Press the transmission button on the back of the thermostat
and check that the LED in the upper corner lights up as a
sign of the thermostat transmitting.
4. If the LED:
does not ash: Change the battery See 2.7 Battery and
changing the battery
does ash: Put the thermostat in transmission mode by
pressing the transmission button for at least 3 seconds (see
5.7 Thermostat in transmission mode). Check with dif-
ferent positions of the thermostat what is interfering with
the transmission.
3.7 Pump control
8-channel base unit
Channel 7 and 8 of this base unit are designed to either be
used for actuators or alternatively for pump control, etc. For
both outputs the pump is started as soon as a thermostat calls
for heat. If the pump is connected to channel 7 it will stop
as soon there is no call for heat. If the pump is connected to
channel 8, it will stop after a 10 minute delay, which means
that the circulation pump continues running as the actua-
tors close. If the pump is connected to channel 8 and “valve
exercise” has been selected in the base unit, the pump will be
exercised daily (see 3.8).
Changing either channel 7 or channel 8 to pump control is
carried out according to 4.4 Pump control.
Note! As long as no thermostat has been registered on channels
7 and 8, the outputs will act as pump outputs. As soon as one
of the other channels is activated, these channels will also be
activated, i.e. if actuator 1 calls for heat, both channel 7 and
channel 8 will be activated. If the underoor heating system
is commissioned in stages and the thermostats are registered
when each heating loop is commissioned, actuators must not
be connected to channels 7 and 8 until their thermostats have
been registered and the heating loops coils have also been com-
missioned.
4-channel Base unit
The pump is connected to the separate pump output. The
pump is started as soon as a thermostat calls for heat and stops
after a 10 minute delay after the last call for heat. If valve exer-
cise is selected (see below), the pump will be exercised daily.
The separate pump output has no LED on the control
panel.
3.8 Valve exercise
Valve exercise is used to prevent the underoor heating
manifold valves from seizing or sticking after a prolonged
inactive period. All the actuators and occasionally the pump
are activated for 5 minutes once a day. The LEDs will
go on and off according to the valve exercise. During this
exercise period LEDs will not ash if any of the thermostats
transmit, but the signals are registered and when the exercise
cycle is completed the actuators will be controlled according
to the signal.
The exercise is performed at the same time of day as the time
when the base unit last time was connected to 230 V. Interrupt
and then re-connect the power at desired time to change the
time of the exercise.
Valve exercise cycle:
• All terminals with a registered thermostat are activated for
5 minutes
• All outlets are closed 5 minutes
• Pump terminal on base unit with 4 outlet and terminal 8
(8-channel if no thermostat is registered) are activated for
5 minutes
• Pump terminal and terminal 8 are closed for 5 minutes
The function is deactivated by setting the valve exercise func-
tion switch in the base unit in position OFF (see Fig 10 and
4.2 Installation and wiring of the base unit).
3.9 Timer module
A timer module, which is used for programmed temperature
set-back, is available for the 8-channel base unit. The timer
is a 2-channel 7-day digital clock, which is supplied recessed
in a new cover to t the base unit. Timer channel 1 controls
the temperature set-back for base unit channel 1, 3, 5 and 7,
and channel 2 controls the temperature set-back for base unit
channel 2, 4, 6 and 8.
For installation see 4.5 Installation of timer module. Settings
are made according to the separate manual supplied with the
timer module.
Fig. 7 Removing and replacing base unit cover.