Hi,
We are modelling a heat recovery in the detailed HVAC simulation. The efficiency of the heat recovery is 80 % when the outside temperature is above 0deg.C but the efficiency drops to 40% if the outside temperature is below 0deg.C.
HR eff- 80% - Outside temp. above 0C HR eff- 40% - Outside temp. below 0C.
Is there any reference EMS available, not specific to this, but anything related to Heat recovery?