STIEBEL ELTRON SOM 8 PLUS - Page 36

36
Depending on whether the bypass is energised by a
valve or by a second pump, a corresponding adjust-
ment can be made in the menu item Variant. De-
pending on the variant, dierent control logics are
applied:
Pump:
In this version, a bypass pump is placed in front of
the collector pump.
The bypass pump is rst activated when store load-
ing is possible. If the switch-on condition is fullled,
the bypass pump is switched o and the collector
circuit pump is activated.
Valve:
A bypass valve is placed into the solar circuit.
The solar heat exchanger is rst bypassed when
store loading is possible. If the above-mentioned
switch-on condition is fullled, the bypass relay
switches the collector circuit via the heat exchanger.
When the valve variant is selected, the option In-
verted is additionally available. When the Inverted
option is activated and the bypass circuit becomes
activated, the relay switches on. When solar loading
starts, the relay switches o again (see gure).
Variant valve:
Variant pump:
Exemplary schematics for the bypass variants
Adjustment
channel
Description Adjustment range / selection Factory setting
Collector Collector eld system dependent system dependent
Relay Bypass relay system dependent system dependent
Variant Variant (pump or valve logic) pump, valve pump
Inverted Valve logic inversion Yes, No No
Sensor Bypass sensor system dependent system dependent
ΔTon
Switch-on temperature dierence 1.0 ... 20.0 K 6.0 K
ΔTo
Switch-o temperature dierence 0.5 ... 19.5 K 4.0 K
Funct. Activation / Deactivation Activ., Deactivated Activ.
Solar / Opt. functions / Add new function... / Bypass
Bypass sensor
Relay
Bypass sensor
Relay
Bypass
Variant valve (inverted):
Bypass sensor
Relay
295931-36390-8667 SOM 8 plus_en.indb 36 20.10.2011 13:14:38