Equest v 3.63 - Pkg Heat Pump - heating output

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While modeling a variable speed blower fan and variable compressor rooftop unit heat pump the Simulation Report lists the EM1 Electricity MBTU for space heating as ?nan?. Does anyone know why I don?t receive a quantity for heating?

In the Air-Side HVAC System Parameters dialog box I?ve selected system type: ?Pkgd Var Vol Var Temp?, Heat Source: ?Heat Pump?, Heating Electric Input Ratio Curves: ?PVVT-Heat-EIR-fEDB&OAT?. My system does not have supplemental electric heat.

Michael Schaefer - P.E., LEED? AP

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Hard to say without seeing your inp and pd2 files.

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While modeling a variable speed blower fan and variable compressor rooftop unit heat pump the Simulation Report lists the EM1 Electricity MBTU for space heating as "nan". Does anyone know why I don?t receive a quantity for heating?
Also when comparing the VAV blower fan Heat Pump (with digital scroll compressor) design with a CV blower fan Heat Pump (Single Stage Compressor) design I only recieve a partial savings in cooling.

I've attached my files for both a CV and VAV volume Heat Pump.

BTW: this is my first time using this software.

Michael Schaefer - P.E., LEED? AP

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Mike,

As a new user, you should use the built-in help menu in most entry
fields by right-clicking and selecting "Item Help".
After that, check the equest-users archives here:
http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/
The "nan" is discussed in a thread here:
http://lists.onebuilding.org/htdig.cgi/equest-users-onebuilding.org/2010
-February/003189.html

Sounds like you have a loop flow that is way out of range (perhaps too
high or zero). If you entered any capacities manually, keep in mind that
"MBtu/h" for the capacity field means millions, not thousands of Btu/h.
If you still can't figure it out, attach your eQUEST project file and
input (.inp) file to a subsequent post.

Regards,

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

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