Heat Pump Protection During Dhw Charging - Siemens RVS41.813 User Manual

Reset integr
electric flow
Release el flow below OT

Heat pump protection during DHW charging

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HVAC Products
If the actual value lies above the switch-off point, the controller switches off the
(controlling) stage switched on last and – based on excess heat, if available – starts to
compute the reset integral.
The next lower stage is switched off when excess heat reaches the set reset integral
(2883).
For a new release, the release integral must be filled again.
The electric immersion heater is released only when the attenuated outside
temperature lies below the temperature set here.
This setting is considered only if the electric immersion heater is used as "Complement
to HP operation" (2880). With the "Substitute" setting, the electric immersion heater is
always released.
The heat pump switches off, when the high-pressure switch response during DHW
charging or because the hot-gas or flow temperature approaches its maximum value.
Parameter "Number DHW charg attempts" (2893) is used to select whether charging
shall immediately be aborted or whether the heat pump shall make a certain number of
charging attempts. In the case of several attempts, the heat pump starts the next
charging attempt each time the minimum off time has elapsed.
If the heat pump shall make only one charging attempt or if, after the selected number
of attempts, the DHW has still not reached the required temperature, DHW charging will
be aborted, the controller will save the current DHW temperature and readjust the
switch-on point to DHW temperature minus the switching differential DHW. With
diagnostics, the saved temperature appears as "Curr DHW charg temp HP" (7093). The
value is maintained until – due to limitation – the heat pump must again abort DHW
charging.
If the "Curr DHW charg temp HP" lies below the adjustable value of "DHW charg temp
HP min" (7092) a maintenance message appears.
If the reduced setpoint lies below "DHW charg temp HP min" and the heat pump can
terminate DHW charging, the controller will not generate a service message.
In the case of sudden setpoint changes, the switch-on point changes to setpoint minus
the switching differential.
User manual RVS61.843, RVS41.813
6 The settings in detail
CE1U2355en_02
28. September 2009