Viessmann SCU345 Manual page 47

COL / OTCO (1, 2) / TCST (1, 2)
Starting time
Adjustment range: 00:00 ... 23:00
in steps of 01:00
Factory setting: 07:00
COL / OTCO (1, 2) / TCEN (1, 2)
Ending time
Adjustment range: 00:30 ... 23:30
in steps of 00:30
Factory setting: 19:00
COL / OTCO (1, 2) / TCRU (1, 2)
Runtime
Adjustment range: 30 ... 500 s
in steps of 5 s
Factory setting: 30 s
COL / OTCO (1, 2) / TCIN (1, 2)
Standstill interval
Adjustment range: 5 ... 60 min
in steps of 00:01
Factory setting: 30 min
This function helps overcome the non-ideal sensor
position with some evacuated tube collectors.
This function operates within an adjusted time frame,
beginning at TCST and ending at TCEN. It activates
the collector circuit pump for an adjustable run-
time (TCRU) between adjustable standstill intervals
(TCIN) in order to compensate for the delayed tem-
perature measurement.
If the runtime TCRU is set to more than 10 s, the
pump will be run at 100 % for the fi rst 10 s of the
runtime. For the remaining runtime, the pump will be
run at the adjusted minimum speed nLO.
If the collector sensor is defective or the collector is
blocked, this function is suppressed or switched off.
2-collector systems
In 2-collector systems, the evacuated tube collector
function is available for each collector fi eld (OTCO2).
If one of the collector fi elds is being loaded, the heat
transfer fl uid fl ows through the inactive fi eld and only
the corresponding relay is energized.
Multi-tank systems
If the evacuated tube collector function is activated,
the speed of the solar pump will decrease to the mini-
mum speed nLO during the loading break time. The
solar loading of the subordinate tank will continue.
In 2-collector systems, the collector fi eld which has
been active before the loading break time remains ac-
tive during the loading break time, unless the evacu-
ated tube collector function of the inactive fi eld be-
comes active.
Antifreeze function
COL (1) / OCFR
Antifreeze function
Selection: ON / OFF
Factory setting: OFF
COL (1) / OCFR / CFR O
Antifreeze temperature on
Adjustment range:
-40.0 ... +9.0 °C [-39.0 ... +48.0 °F]
in steps of 0.5 °C [1.0 °F]
Factory setting: +4.0 °C [+40.0 °F]
47