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I built a model to simulate a water-cool DX unit with water-side economizer. The DX unit is modeled as a unitary water-to-air heat pump with electric reheat, as shown below:

I look into the total clg/htg rate of the unitary HP (purple and orange) and clg/htg rate of its coils (light blue), also the enthalpy of inlet and outlet nodes of the HP (green). These numbers don't make much sense to me. Why the outlet enthalpy is higher than the inlet while the unitary HP total cooling rate is >0 and total heating rate=0? And why the water-to-air HP cooling coil's total cooling rate=0 but the unitary HP's total cooling rate>0?

Thanks in advance.

I built a model to simulate a water-cool DX unit with water-side economizer. The DX unit is modeled as a unitary water-to-air heat pump with electric reheat, as shown below:

I look into the total clg/htg rate of the unitary HP (purple and orange) and clg/htg rate of its coils (light blue), also the enthalpy of inlet and outlet nodes of the HP (green). These numbers don't make much sense to me. Why the outlet enthalpy is higher than the inlet while the unitary HP total cooling rate is >0 and total heating rate=0? And why the water-to-air HP cooling coil's total cooling rate=0 but the unitary HP's total cooling rate>0?

Thanks in advance.

I built a model to simulate a water-cool DX unit with water-side economizer. The DX unit is modeled as a unitary water-to-air heat pump with electric reheat, as shown below:

I look into the total clg/htg rate of the unitary HP (purple and orange) and clg/htg rate of its coils (light blue), also the enthalpy of inlet and outlet nodes of the HP (green). These numbers don't make much sense to me. Why the outlet enthalpy is higher than the inlet while the unitary HP total cooling rate is >0 and total heating rate=0? And why the water-to-air HP cooling coil's total cooling rate=0 but the unitary HP's total cooling rate>0?

Thanks in advance.