Raising The Reduced Room Temperature Setpoint; Forced Charging; Idle Heat Function; General - Siemens RVD110 Basic Documentation

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HVAC Products
19.6 Raising the reduced room temperature set-
point
The reduced room temperature setpoint can be raised as the outside temperature falls.
This ensures that
• at low outside temperatures, the required change from the reduced setpoint to the
nominal setpoint will not become too great
• no peak load will occur during the heating up phase
The reduced room temperature setpoint is only raised at outside temperatures below
5 °C. This is not required at higher outside temperatures. The effect (authority) below
5 °C can be adjusted (operating line 161). To be set is the setpoint lift per °C outside
temperature drop. The setting range is 0 to 10, but the effective value is ten times
smaller.
The outside temperature used is the composite outside temperature.
The setting is to be made on operating line 161.
The function can be deactivated.
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19.7

Forced charging

In the case of forced charging, the storage tank will also be charged when the d.h.w.
has not yet dropped below the setpoint by the amount of the switching differential.
This takes place:
• Every day at the beginning of the first release phase when d.h.w. heating is released
according to the program selected on operating line 101, or
• Every day at midnight when d.h.w. heating is always released
Forced charging will be switched off when the d.h.w. setpoint is reached. Forced charg-
ing is only active with plant types no. 2 and 3, and 6 through 8. This function can be
deactivated on operating line 162.
19.8

Idle heat function

19.8.1 General

The idle heat function can only be provided with plant types no. 4 and no. 5. The objec-
tive is to prevent the primary side of the d.h.w. heat exchanger from cooling down.
Cooling down occurs (leading to long waiting times when d.h.w. is needed) when, dur-
ing longer periods of time,
• no heat is required for space heating, and
• no d.h.w. is consumed
This function can be provided with or without sensor B7. It can be deactivated, if re-
quired.
Basic Documentation RVD110, RVD130
19 Function block Locking functions
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CE1P2381E
27.05.2004