Viessmann VITODENS 100-W Installation And Service Instructions Manual page 52

Installation sequence
Commissioning and testing
Domestic hot water flow rate and temperature (Combi boiler
only)
A flow regulator is fitted to ensure that no adjustment of maximum flow is neces-
sary.
Comfort function (Combi boiler only)
When the comfort function is selected, the instantaneous water heater will be
held at temperature (standby). This makes DHW available quickly.
Enabling the comfort function
52
(cont.)
8. Open the gas shut-off valve and
start the boiler.
Danger
Gas escaping from the test
nipple leads to a risk of
explosion.
Check test nipple A for
soundness.
Setting DHW temperature:
Set rotary selector tw to the desired
DHW temperature.
Turn the rotary selector tw briefly
and fully clockwise (shorter than 3 s),
and then turn it anti-clockwise. The
display will then show "COMFORT".