Hi there, I have a question regarding VRF efficiencies. We have an office building that have VRF with heat pump systems that provide cooling and heating. ASHRAE 90.1-2010 has two tables that address VRF efficiencies: Table 6.8.1 I – Variable Refrigerant Air Conditioners and Table 6.8.1 J – Variable Refrigerant Air-to-Air and Applied Heat Pumps.
After analyzing both we realized that cooling efficiencies between these two tables varied. Is this because Table 6.8.1 I applies to only cooling VRF systems and Table 6.8.1 J applies to VRF systems that provide heating and cooling? Therefore, should we compare the VRF systems installed in our building with Table 6.8.1 J?
Thanks in advance!
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5907 thumbs up
October 26, 2017 - 2:15 pm
Yes the two tables are for air conditioners only and heat pumps. If you have VRF heat pumps then you should use 6.8.1J.