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Solutions for centralized heating systems installations
Cascade installation schemes
Plant with three condensing boilers Luna Platinum in cascade
– 2 high temperature direct circuits – 2 mixed circuits and
one heater load circuit DHW
For complete management of the cascade you must install Bus Module OCI345 (one in each boiler in cascade), and an expansion
module AVS75 external to the cascade.
The figure shows the connection of the OCI345s and Expansion Module AVS75.
The connections of Expansion Module AVS75 are highlighted in the figure.
KEY FOR CONNECTOR HOOK-UP
AVS 75
n
n
n
X30
BX21
M
BX22
M
H2
M
X50
L
N
L
N
QX21
N
L QX22
QX23
T
S
C
L
FX23
EX21
2
1
1 2
3
1 2
ON
X50
Connector for hook up between SIEMENS electronic board and
accessory AVS 75
C (EX21-FX23)
Not used for cascades
C (FX23-L)
Safety thermostat 230V, not used for cascades
S (QX23-L)
Relay outlet 230V programmable
T (QX21-N)
Relay outlet 230V supplying CASCADE PUMP
T (QX22-N)
Relay outlet 230V supply any loading PUMP for sanitary water
STORAGE
NOL (L-N)
Supply AVS 75
n (H2-M)
AMBIANCE THERMOSTAT connector
n (BX22-M)
CASCADE DELIVERY PROBE inlet
n (BX21-M)
CASCADE RETURN PROBE inlet
M
Common sensor earth
For correct plant management you must carry out modifications of the parameters of all the cascade boilers. The first one to
configure is the MASTER.
