Baseline Heat Pump vs Geothermal HP

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Hello, I am becoming concerned with how much better my geothermal Heat Pump modeled as PVVT (with geo HP under heating cooling respectively) are performing over the Ashrae Baseline required system 4 (Packaged Single Zone HP). I am approaching the 40-50% mark. I understand that the geothermal system should be appreciably less in energy consumption since there is little energy spent on the heat sink other than pumps. Both were specified by Equest through wizard selection, but the PVVT Geo HP system was confirmed to be the best selection for a multizone system in a Equest users response. Am I correct in thinking that the Single Zone HP are incorrectly duplicating themselves for each zone serviced? Therefore, increasing the energy consumption. Whereas, each PVVT system can service multiple zones. Should I use the PVVT system for the baseline and modify it to simulate a PSZ-HP? Thanks for any help.

Nicholas Fonner
Energy Modeling Group
Henneman Engineering, Inc. | energy. focused.
1605 South State Street, Champaign, IL 61820
V 217.359.1514 | F 217.359.9354 | C
www.henneman.com | nfonner@henneman.com

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The default fan control for PVVT is variable speed. If your geothermal heat pumps are constant speed, which is more typical, you will need to change that.

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________________________________
Keith Swartz, P.E., LEED AP

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Also, the water loop pressure drop may not default to a reasonable number.
I'd recommend examining the water loop pressure drops in detailed edit mode to see if they match your design / intuitions.

Aaron Dahlstrom , PE, LEED(r) AP

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