Internal Extension H1; Internal Extensions - Viessmann VITODENS 222-F Installation And Service Instructions Manual

Function description
Weather-compensated control unit
The DHW is controlled to the specified
temperature via the cylinder temperature
sensor.
The primary cylinder continues to be
heated up after the draw off process has
terminated, until the set DHW tempera-
ture has been reached at the cylinder
temperature sensor.

Internal extensions

Internal extension H1

The internal extension H1 is integrated
into the control unit casing. The cylinder
primary pump is connected to relay out-
put sK.
116
(cont.)
The cylinder primary pump and the
three-way diverter valve remain ON for a
further 30 s.
An external safety valve can be connec-
ted to gD.