Viessmann VITOTRONIC 200 Service Instructions Manual page 14

Function description
Heat pump cascade
G 2nd lag heat pump
Connection to the contact for "exter-
nal demand"
H Floating contact "external demand"
K 3rd lag heat pump
Subject to the system equipment level,
the parameter "Use of heat pumps in
cascade 700C" at the lead appliance
can be used to set all the lag heat pumps
to be used for central heating/cooling
and/or for DHW heating.
The changeover between central heat-
ing/cooling and DHW heating is effected
by a central 3-way diverter valve that is
controlled by the lead appliance. If the
lag heat pumps also use 3-way diverter
valves to change over, then the corre-
sponding switching outputs at their heat
pump control units must be connected to
the central diverter valve in parallel.
Parameter
"System scheme 7000"
"External extension 7010"
"Cascade control 700A"
"Number of lag heat pumps in
cascade 5735"
"Output lag heat pump 700B"
"Use of heat pump in cascade
700C"
"Flow temperature for external
demand 730C"
"Enable three-way diverter
valve heating/DHW 730D"
14
(cont.)
L Central fault message input, lag
Lag heat pump faults are reported to the
lead appliance ("E2 Lag heat pump").
Lead appliance
"0" to "255"
heat pump
Open contact X3.10 / X3.11 triggers
a message
Setting
Lag heat pump
"0" to "10"
"1"
"1"
"1" to "3"
"0" to "3"
—
"1"
"11"
"0"
"0"
—
—
—
"0" to "700"
(≙ 0 to 70 °C)
"1"