Flow Heating - Siemens RVS41.813 User Manual

Flow rate
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HVAC Products
Example 1: Pulse unit heat numer= 10
Pulse unit heat denom = 1
Pulse unit heat = Liter
Pulse valency = 10 liters / pulse
Example 2: Pulse unit heat numer = 1
Pulse unit heat denom = 1
Pulse unit heat = kWh
Pulse valency = 1 pulse / kWh
Line no. Operating line
3097

Flow heating

3098 Flow DHW
The volume calculation can be used in place of the volume flow measurement with
pulse metering. This function calculates, using an adjustable flow performance, the
runtime and rpms the theoretical volume flow through the condenser.
Volume [l] = runtime [Min] / 60 * rpms [%] * flow performance [l/h]
The flow performance can be entered separately for heating operation and DHW
heating.
Runtime is recorded at an accuracy of 1 minute. For heating, the state of condenser
pump Q9 is recorded, for DHW heating the state of the charge pump/diverting valve
Q3.
The determine volume is multiplied by the measured temperature difference and added
as heating energy in the counter for supplied heat.
Supplied heat energy can be recorded with this function and measuring the
temperature difference without installing a heat meter. The flow (B21) and return
temperature (B71) on the condenser are measured. The temperature difference
(temperature difference dT = flow temperature HP (B21) – return temperature HP
(B71))
and the water volume flowing through the condenser (pulse count or volume
calculation) can be used to calculate heating energy.
The temperature difference is measured for heat flow (dT>0) only. dT=0 is the limit for
negative differences (cooling flow). The calculation of the supplied heating energy is
zero as well and the cooling flow is therefore not counted.
To achieve sufficient accuracy for the temperature difference, we recommend
calibrated both sensors B21 and B71 relative to one another.
The function must be switched off via both parameters ("---") if metering of heating
energy via volume calculations is not desired.
User manual RVS61.843, RVS41.813
6 The settings in detail
CE1U2355en_02
28. September 2009