Viessmann VITOCAL 242-G Installation And Service Instructions Manual page 17

Function description of systems
Overview of the internal components
HR Heating return
HV Heating flow
KW Cold water (connections, see
from page 94)
RL Solar return (only Vitocal 242)
VL Solar flow (only Vitocal 242)
WW DHW
Z DHW circulation
A Primary return (primary outlet)
B Primary flow (primary inlet)
C Flow temperature sensor; sec-
ondary circuit
D Instantaneous heating water
heater
E Secondary pump
F Three-way diverter valve "Cen-
tral heating/DHW"
G Plate-type heat exchanger for
cylinder heating
Preparing for installation
(cont.)
H Upper cylinder temperature sen-
sor
K Return temperature sensor of
the solar circuit (only
Vitocal 242)
L Solar circuit pump (only
Vitocal 242)
M Lower cylinder temperature sen-
sor
N DHW cylinder
O Solar heat exchanger (only
Vitocal 242)
P Three-way diverter valve
(manual) (only Vitocal 242)
R Cylinder primary pump
S Return temperature sensor; sec-
ondary circuit
T Heat pump module
U Primary pump
17