Testing The High Limit Safety Cut-Out - Viessmann VITOTRONIC 100 Installation And Service Instructions Manual

Commissioning

Testing the high limit safety cut-out

1. Hold down the TEST key (position
), until the burner has shut down:
Pressing the TEST key bypasses
thermostat . The high limit safety
cut-out switches the burner OFF,
as soon as the boiler water tem-
perature reaches the safety tem-
perature.
2. Release the TEST key.
Matching up coding addresses
Subject to the equipment level, the
control unit must be matched to the
system.
Checking outputs (actuators) and sensors
Carrying out a relay test
1. Press G and d simultaneously
for approx. 2 s.
Relay test is activated.
2. Control relay outputs with a/b.
The following relay outputs may be selected:
Display screen Explanation
1 Burner ON
2 Burner stage 1 + 2 ON (if the two-stage burner extension is
connected)
3 Heating circuit pump ON
4 Cylinder primary pump ON
22
3. Wait until the boiler water tempera-
ture has dropped approx. 15 to
20 K below the selected safety
temperature.
4. Reset the high limit safety cut-out
by pressing .
For coding steps and an overview of
codes, see page 37.
3. Press d.
Relay test is completed.