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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
Description of the heating engineer settings
18.10.2002
4.138 Flow / return temperature differential
at –10 °C
•
Heat pump return temperature sensor can be used as a control sensor
If return temperature sensor B71 is used as a control sensor, a setpoint must be pro-
vided for it. For that purpose, the flow temperature setpoint (heating curve) considers
the temperature differential set here.
This operating line is of importance only if return temperature sensor B71 is used as a
control sensor for the heat pump (operating line 420, settings 2, 4, 5 and 8).
Setting range
Unit
Factory setting
1...30 K
8
To obtain the current return temperature setpoint, the current flow temperature setpoint
(according to the heating curve) is reduced by the current temperature differential.
For that purpose, the entered temperature differential between flow and return (at an
outside temperature of –10 °C) is converted to the composite outside temperature (op-
erating line 705).
This means that at an outside temperature of –10 °C, the flow temperature setpoint is
reduced by the value adjusted above (standard = 8 K) and, at an outside temperature
of 20 °C, there will be no more reduction.
20.00 18.00 16.00 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0.00 -2.00 -4.00 -6.00 -8.00 -10.00
55.00
50.00
45.00
40.00
35.00
30.00
25.00
°C
°C
65.00
23
92
D
06
20.00
60.00
70.00
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Aussentemperatur
Benefit
Description
Note
Setting
Effect
