VDH ALFA 71 MODulation User Manual

User manual
ALFA 71 MODulation
Thermostat.
0-100  C
VDH doc. 080349
Software: ALFA71MOD100

* Installation.

On the top side of the ALFA 71 MOD is shown how the sensors, power supply and relays has to be
connected.
After connecting the ALFA 71 MOD to the power supply, a self test function is started. As this test
is finished the measured temperature appears in the display.

* Control.

The ALFA 71 MOD thermostat can be controlled by four pushbuttons on the front. These keys are:
SET - view / change the setpoint.
UP - increase the setpoint.
DOWN - decrease the setpoint.
C - hidden push button above the SET key and behind C symbol.

* Viewing set point.

By pushing the SET key the set point appears in the display. The decimal point of the last display
starts blinking. A few seconds after releasing the SET key the setpoint disappears and the
measured temperature is shown again in the display.

* Changing set point.

Push the SET key and the set point appears in the display. Release the SET key. Now push the
SET key again together with the UP or DOWN keys to change the setpoint. A few seconds after
releasing the keys the measured temperature shows again in the display.

* Status of the Relays.

By pushing the hidden C key the display shows the status of the relays. Each display segment
shows the status of the relay output, showing 0=off and 1=on. The code 110 means relay 1 and 2
are on and relay 3 is off.

* Readout valve position.

By pushing the UP key the display shows the current valve position.
Version: v1.0
File: DO080349.WPD
1
Date: 07-03-2008
Range: 0/+100,0  C