Siemens Climatix S300 HRV Application Manual page 98

Application functionalities
5
Energy Recovery
Exhaust side
Supply side
Available parameters
98 | 170
ERC efficiency calculation
TOa Outside air [°C]
TEx Extract air temperature [°C]
TSuAfHexg Supply temperature after heat
exchanger [°C]
Efficiency n is calculated on the exhaust side by the following formula:
n = (TEx – TEh) / (TEx – TOa)
In case the preheating coil is active, TSuAfPreHcl is used instead of TOa. If the
sensor is not available while the preheating coil is active, the efficiency is
unreliable.
If an additional supply air sensor after the heat exchanger is available, the
efficiency n is calculated on supply and exhaust side as:
n = 0.5 * (TEx – TEh) / (TEx – TOa) + 0.5 * (TSuAfHexg – TOa) / (TEx – TOa)
Efficiency calculation requires at least outside temperature, extract temperature
and exhaust temperature sensors.
Current values
ERC efficiency
TEh Exhaust air temperature [°C]
TSuAfPreHcl Supply temperature after
preheating coil [°C]
BACnet object R/RW
PrHExgEfcy R
AVAL,161
A6V10733786_en_c
Note
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