Unical PELLEXIA 80, Instructions For Installation, Use And Maintenance Manual

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CALDAIA PELLEXIA
VASO
ESPANSIONE
POMPA 4
RICIRCOLO
POMPA 3
IMPIANTO
RISCALDAMENTO
VALVOLA
MISCELATRICE
MANUALE
POMPA 2
BOLLITORE
S 4
S 5
SCAMBIATORE AD
ACCUMULO
S 3
S 2
3.11.4 - PELLEXIA BOILER SYSTEM FOR HEATING AND FOR THE PRODUCTION OF
DOMESTIC HOT WATER, WITH PUFFER
This diagram shows a stratification heat storage tank for the
production of domestic hot water.
The diagram shows the
P4 recirculation pump, the P3 heating
system pump, and the P2 storage tank pump.
NB: The P4 recirculation and balancing pump is essential;
it serves the purpose of balancing the flow and return tem-
perature of the boiler and adds cold water when necessary
to prevent the risk of condensation. A mixing valve is es-
sential in several areas of the system.
The S3 and S2 probes are required in this configuration.
The P2 storage tank pump is enabled when the boiler tempera-
ture (the
S4
probe) is above the minimum boiler temperature
(normally 60°C).
The storage tank pump is enabled when the
S4 boiler flow
probe detects a temperature above that of the
S2
probe plus a
heat differential (normally 6°C).
Running the heating system:
In this configuration, the
P3 heating system pump is connected
directly to the storage tank and depends, therefore, not on the
boiler temperature but on the temperature of the storage tank.
The S3 probe controls the heating circuit.
If the temperature of the storage tank is, therefore, equal to or
greater than the minimum temperature, the input chronother-
mostat enables the heating system pump even when the boiler
is cold.
Sensor legend:
S2 : temperature sensor at base of storage tank
S3 : temperature sensor at top of storage tank
S4
: flow temperature sensor of the boiler
: return temperature sensor of the boiler
ATTENTION:
In the case of a system with closed expan-
sion vessel, the installer must assemble a
minimum/maximum water pressure switch
and the safety heat exchanger.
PELLEXIA BOILER
EXPANSION
VESSEL
HEATING SYSTEM
PUMP 3
BOILER PUMP 2
MANUAL
MIXING VALVE
RECIRCULATION
PUMP 4
STORAGE
EXCHANGER