I have created some heat recovery calculations for a VRF system following the Energy Trust of Oregon guidelines and I am getting some underwhelming savings.

The project is a 4-story office building, one of the floors is a basement, and there is approximately 9000 SF per floor. 1 VRF air cooled unit per floor except for the third, where there are two. There might not be enough load diversity between zones to generate much heat recovery. One strange thing is that I am getting negative elec input to heat/cool numbers exported from the CSV hourly reports. Has anybody encountered this before?

I have attached my excel file for reference (sorry for the size - not sure how to compress an excel file). Any feedback would be much appreciated. Thanks in advance for your help.

Travis Miller, PE
DC Engineering
O: 406-829-8828; x. 209
123 W. Spruce ST.
Missoula, MT 59802
www.dcengineering.net