Crankcase heating in Appendix G

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I am working on a reply to some LEED reviewer questions regarding crank
case heating for a PSZ-AC system type for a LEED building. The project
is registered under 90.1 - 2004. The eQuest system type "Packages single
zone" defaults to 0.5 kW of crank case heating which I left in both
models since my proposed model uses the same type system and crankcase
in necessary in the northwest.

The reviewer commented that "because Appendix G does not explicitly
address crankcase heating, it should not be modeled in the baseline
case". This seems to imply that if it is included in the installed units
it need to be in the proposed model, but I need to remove it from the
baseline causing an unfair energy difference.

I didn't find any CIR's, but does anyone have any suggestions?
--

Jacob Goodman , LEED AP

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Jacob,

Personally, I think the crankcase heating should be allowed in both the
proposed and baseline models if it is required for that system type in
your region. That is how I have been modeling it. As a compromise, you
could determine the annual crankcase energy by modeling the proposed
with and without it, then take it out of all proposed and baseline
systems and add the same amount as an identical process load in both the
proposed and baseline models.

Regards,

William Bishop, PE, BEMP, LEED(r) AP

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