Available parameters
Actual values
BACnet object
R/RW
Note
Heat exchanger condensation monitoring
HExgCdnMon
BI,75 (D1)
BI,92 (D2)
BI,109 (X3)
BI,126 (X8)
R
Basic settings for efficiency alarm
BACnet object
R/RW
Note
Min difference between extract and outside air
temperature
DiffTExTOaMin
AVAL,382
RW
K
Min difference between extract and exhaust
temperature
TDHExgTErr
AVAL,381
RW
K
Efficiency supervision delay time
TiDlyHExgTErr
PINTVAL,149
RW
sec.
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
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,372
R
%
Application functionalities
Energy Recovery
5
110 | 170
A6V10733786_en_c
