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15
System Overview Multiple Units in Series
Cascade Connection
Name
Description
Location
Name
Description
Location
P1
Indoor side water pump
Internal
(option)
RT
Indoor side inlet water
temperature sensor
Internal
EXP
Expansion tank
External
ST
Indoor side outlet water
temperature sensor
Internal
SAK
Safety valve
External
HT
Hot water temperature sensor
Internal
FS
Automatic water
supplement valve
External
STo
Outdoor side outlet water
temperature sensor
Internal
CV
Non-return valve
External
ET
Exhaust gas temp. sensor
Internal
FL
Particle filter
External
VVB
Hot water cylinder
External
AIV
Air vent valve
External
Systems Overview (Indoor side)