Emergency Operation - Rotex HPSU compact 304 Installation And Maintenance Manual

8.5 Emergency operation

In the case of incorrect setting in the electronic control system,
emergency heating operation can be maintained by activating the
special "Handbetrieb" function on the control unit (see operating
manual for the control unit).
If the 3-way valves are intact, the ROTEX HPSU compact
switches to Heating mode. The necessary flow temperature can
be adjusted with the rotary switch:
A storage charge can be realised using the special "Handbe-
trieb" function,
Remove the valve drive of the 3-way diverter valve 3UV
DHW (see fig. 7-3). To do so, press the unlock button on the
valve drive (see fig. 7-3, pos. 5.2) and turn the valve drive a
1/8-turn anti-clockwise (bayonet socket).
When the valve drive is removed, the AB-B path is
opened.
Should the valve drive of the 3-way diverter valve 3UVB1 be
defective, a Parallel operating mode can be enforced. For this:
Remove valve drive from both 3-way diverter valves 3UVB1
+ 3UV DHW.
The flow temperature is configured for storage charging
by means of heat absorption in the heat exchanger (series
switching).
In order to prevent a malfunction due to a low flow level,
when the valve drive of the 3-way diverter valve 3UVB1
has been removed, sufficient heat absorption must be
ensured in the heating system.
Open actuators in the heat distribution network.
Set flow temperature as low as possible.
FA ROTEX HPSU compact 4 - 06/2015
8 x Errors, malfunctions and messages
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