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Premium Commercial Controls
ERV
SYSTEM MONITORING
12.9.5.4 Economizer Control
The economizer will be enabled when there is a call for cooling and the outdoor is more
favorable than the return air. In this case it will open the bypass damper to bypass the enthalpic
core and thus inhibit the exchange of energy. During this time the unit still uses 100% OA.
Economizing is allowed when both of the following Are below their limit:
u
Holding Register 30 “Economizer.Econ_Low_OA_Temp_Limit”
u
Holding Register 42 “Economizer.Econ_Low_RA_Temp_Limit”
12.9.6 Frost Control
The frost control function is enabled, when the OA is lower than Holding Register 64 “Defrost_
OA_SetP.Val” minus Holding Register 66 “Defrost_OA_SetP.DBright,” and turns off again when
the OA exceeds the HR66. During this time, the supply fan is OFF and the OA damper is closed.
12.9.7 Filter Monitoring
Filter pressures are read through Input Register 16 “RA_Flt_Press.Val” and Input Register 18
“OA_Flt_Press.Val.”
Filter alarm levels are set at Holding Register 0 (or 98) “RA_Flt_AlarmHigh” and Holding
Register 2 “OA_Flt_AlarmHigh.”
12.9.8 Exhaust Fan Only Mode
If BMS control is enabled, the unit can also be put in exhaust fan only mode in occupied
operation using Coil 1 “UnitOnOffMng.BMSEFOnly.”
