ERC efficiency calculation
TOa
Outside air [°C]
TEh
Exhaust air temperature [°C]
TEx
Extract air temperature [°C]
TSuAfPreHcl
Supply temperature after
preheating coil [°C]
TSuAfHexg
Supply temperature after heat
exchanger [°C]
Exhaust side
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.
Supply side
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.
Available parameters
Current values
BACnet object
R/RW
Note
ERC efficiency
PrHExgEfcy
AVAL,357
R
%
Application functionalities
Energy Recovery
5
106 | 170
A6V10733786_en_c
