Gewiss GW 20 827, User Instructions

Page: 39 / 136

39
E
N
G
L
I
S
H
The time-thermostat has a serial connection for connecting to the GSM GW 90 821 remote
control unit. Using SMS command (e.g. from a cellular telephone) it is possible to:
• set the type of operation (air conditioning/heating)
• set the operating mode (manual/automatic/OFF)
• set the operating set point (MAN mode only)
• request the current status
The device replies to each command SMS sent with a confirmatory SMS (with a predefined,
non-configurable text); the status request message will generate a reply that includes the
following information:
• current type of operation (heating/air conditioning)
• current operating mode (OFF/AUTO/MAN)
• currently set set point temperature
• measured ambient temperature
• output status (ON/OFF)
The
symbol is displayed on the VDU whenever the operating type or mode are modified
using the remote control unit.
The device is fitted with a backup battery that guarantees updating of the time and the day
of the week in the case of a blackout. There is an autonomy of 24 hours under the follow-
ing conditions when the power supply is provided exclusively by the battery:
• display time active
• measure and temperature display not active (dashes are displayed)
• backlighting not active
• relay switching not enabled (the relay contact is open)
• front keys not active (except the simultaneous pressing of all four keys). In the absence
of the power supply the simultaneous pressing of all four front keys causes disconnec-
tion of the backup battery inside the device.
This function is used to conserve the efficiency of the battery when the device is not used
for a long period. The battery is automatically reconnected once the device is connected to
the electricity mains network. The set programs are not lost either in the case of a black-
out or in the case of battery disconnection.
Operating in the case of a blackout
Remote control