Internal Extensions For External Connections - Viessmann Vitodens 333-F Service Instructions Manual

Function description
Weather-compensated control unit
The cylinder primary pump and the
three-way diverter valve remain ON
for a further 30 s.

Internal extensions for external connections

Internal extension H1
The internal extension H1 is inte-
grated into the control unit casing.
The cylinder primary pump is con-
nected to relay output sK.
104
(cont.)
An external safety valve can be con-
nected to gD.