19
Heat pump cascade: 2-stage (type BW 302.D090 to BW 302.D230)
A heat pump cascade consists of a lead heat pump
and lag heat pumps.
Each lag heat pump has a heat pump control unit.
Both the lead and lag heat pumps can have 2 stages.
The lead heat pump regulates the operation of the
heat pumps within the cascade.
■
Up to 4 lag heat pumps possible when connected via
LON.
The following communication modules (accessories)
must be fitted in the heat pump control units:
–
LON cascade communication module in the lead
heat pump
–
LON communication module in lag heat pumps
Hydraulic installation scheme
IV
III
II
I
Fig. 13
A
Interface to heating water buffer cylinder
(return)
C
Interface to the separate cooling circuit or heat-
ing/cooling circuit
H
Interface to heating water buffer cylinder (flow)
P
Interface to primary circuit (flow)
Q
Interface to primary circuit (return)
W
Interface to the DHW cylinder
I
Lead heat pump in the heat pump cascade
(1-stage or 2-stage)
II to IV Lag heat pump in the heat pump cascade
(1-stage or 2-stage respectively)
Equipment required
Pos.
Description
Heat generator
1
Heat pumps
2
Heat pump control unit
3
Outside temperature sensor
4
LON communication module for cascade control of the lead heat pump I
LON communication module for lag heat pumps II to IV
5
Secondary pump 1 (fail-safe)
6
Circulation pump for cylinder heating (fail-safe)
Preparing for installation
Hydraulic connection requirements
(cont.)
5838144
Installation
Summary of Contents for Vitocal 300-G Pro BW 302.D090
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