Alfa Laval Micro
Installation, service and operating instruction
10 Basic operation of the system CM721
10.1
Setting one temperature for the whole day
To operate as a simple thermostat with one temperature throughout the day, select the manual operating mode
by pressing the MAN button. Adjust the temperature by pressing the
anywhere from 5°C to 35°C in 0.5°C steps. The thermostat will continue to maintain this temperature until
another operating mode is selected or the temperature is adjusted.
10.2
Automatic operation
The relay box receives the heat demand (0-100%)
signal from the room thermostat. The room
thermostat will display the
display whenever more heat is required. Depending
on the demand the relay box will switch the heating
device on to match the current requirements of the
system.
The green LED indicates the status of the relay
output:
• Green LED on = relay on
• Green LED off = relay off
10.3
Temporary manual override
Pressing the relay box button will override the current relay position.
As soon as the next signal is received from the room thermostat the relay
box will return back to automatic operation as the automatic control has
higher priority than manual operation.
10.4
Communications loss
If the RF communication is lost for a period of 1 hour the red LED on the relay box
will illuminate to indicate that no RF messages have been received during the last
hour.
The factory setting keeps the relay permanently off when communications is lost.
The factory settings can be changed, see
setup.
To allow manual control of the relay box output, manual override is available in fail-
safe mode. See
10.3 Temporary manual override.
When RF communication is restored the relay box will automatically return to
normal operation.
All manuals and user guides at all-guides.com
symbol on the LCD
11.2 BDR91 relay box fail safe mode
34
or
buttons - this can be set
Picture 28
Picture 29
Picture 30