8
Par Using the navigation key ^_ allows you to select the desired parameter while you are in
the program mode. Press the selection key ò once to select the parameter in the window.
Selected parameter blinks allowing you to modify it. You can modify the selected parameter
while the middle window blinks by pressing the ï or ð key. The unit accepts the new value by
pressing the ñ key once.
RUV 2.0 – This display shows the software revision number.
NR O – This indicates the USDT 2004B employment as a basic solar hot water heating controller.
PROGRAMMING THE TEMPERATURE RANGE
USDT 2004B is factory set at T2 > 160 oF PUMP OFF, T2 < 150 oF PUMP ON. The user may
program a different temperature range (hysteresis bandwidth) if required. In this case, there are
two temperatures that should be entered:
Tank Overheating Protection
User can program hysteresis (temperature range for output control) by using max? and max=.
For
max?1 Pump stops above tank temperature (T2)
max=1 Pump runs again below this set point (T2)
Temperature Differential Adjustment
diff=1 Pump runs when temperature difference between collector T1 (collector) and T2
(tank) exceeds this value. Factory setting is 15 oF. Consult your collector
manufacturer for the recommended value.
diff?1 Pump stops when temperature difference between collector T1 (collector) and T2
(tank) reaches this value. Factory setting is 7 oF. Consult your collector
manufacturer for the recommended value.