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Installation
Indications,
functions and options
Messages
Commissioning
Operation and function
OHDP
Heat dump option
Selection: ON / OFF
Factory setting: OFF
OTCL
Overtemperature collector
Adjustment range:
40 … 160 °C
Factory setting: 110 °C
OTPUM
Pump or valve logic
Selection: ON / OFF
Factory setting: OFF
HDREL
Heat dump relay
Selection: system-dependent
Factory setting: 3
7 Heat dump
The Heat dump function can be used to direct excess heat generated by strong
solar irradiation to an external heat exchanger (e. g. fan coil) in order to keep the
collector temperature within the operating range.
The heat dump function can either use an additional pump or valve (OTPUM
ON = pump logic, OTPUM OFF = valve logic).
Variant pump:
The allocated relay is energised with 100 %, if the collector temperature reaches
the adjusted switch-on temperature.
If the collector temperature falls by 5 K below the adjusted collector overtemper-
ature, the relay will be switched off. In the variant pump, the heat dump function
works independently from solar loading.
Variant valve:
The allocated relay will be energised in parallel to the solar pump, if the collector
temperature reaches the adjusted collector overtemperature. If the collector tem-
perature falls by 5 K below the adjusted collector overtemperature, the relay will
be switched off.
Note:
The adjustable value OTCL is blocked against the collector emergency
temperature CEM by 10 K This function will only be available if the col-
lector cooling function, the heat dump function, and the drainback option
are deactivated.
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