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External heat exchanger for all consumers
Heat exchanger relay switches the solar circuit pump (primary
pump R
p
)
Heat exchanger relay switches the secondary pump R
s
S1
R4
S2
S4
Rp
R1
1
2
S9
S1
S2
S4
R1
1
2
S9
Rs
R2
R4
– When the start temperature differential
"ΔTon"
between collector
temperature sensor S1 and cylinder temperature sensor S2 or S4 is
exceeded, the solar circuit pump (primary pump R
p
) is switched on.
– When the start temperature differential
"HE ΔTon"
between heat
exchanger sensor S9 and cylinder temperature sensor S2 or S4 is
exceeded, the relevant circulation pump R1 or R4 is switched on to
heat the consumers.
– When the start temperature differential
"ΔTon"
between collector
temperature sensor S1 and cylinder temperature sensor S2 or S4
is exceeded, solar circuit pump R1 is switched on and the relevant
valve R2 or R4 is opened to heat the consumers.
– When the start temperature differential
"HE ΔTon"
between heat
exchanger sensor S9 and cylinder temperature sensor S2 or S4 is
exceeded, secondary pump R
s
is switched on.
External heat exchanger for one consumer
Heat exchanger relay switches the solar circuit pump (primary
pump R
p
)
Heat exchanger relay switches the secondary pump R
s
S1
R4
Rp
S9
S2
S4
R2
1
2
S1
R2
R4
S2
S4
R1
1
2
R
S9
S
– When the start temperature differential
"ΔTon"
between collector
temperature sensor S1 and cylinder temperature sensor S2 or S4 is
exceeded, the solar circuit pump (primary pump R
p
) or circulation
pump R4 is switched on.
– When the start temperature differential
"HE ΔTon"
between heat
exchanger sensor S9 and cylinder temperature sensor S2 is excee-
ded, circulation pump R2 is switched on to heat consumer 1.
– When the start temperature differential
"ΔTon"
between collector
temperature sensor S1 and cylinder temperature sensor S2 or S4
is exceeded, solar circuit pump R1 is switched on and the relevant
valve R2 or R4 is opened to heat the consumers.
– When the start temperature differential
"HE ΔTon"
between heat
exchanger sensor S9 and cylinder temperature sensor S2 is ex-
ceeded, secondary pump R
s
is switched on to heat consumer 1.
External heat exchanger in large solar thermal systems
In large solar thermal systems with long solar lines in areas without
frost protection, a 3-way valve for frost protection of the plate heat
exchanger must be installed. This prevents the flow of cold heat
transfer medium into the plate heat exchanger, potentially causing it
to freeze up.
M
D
B
C
A
A
Plate heat exchanger
B
Temperature sensor
Solar control units
(cont.)
34
VIESMANN
VITOSOL
6
5822 440 GB