[Equest-users] Fan Power for GSHP units

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Hi all,

I am modeling a GSHP system for a LEED project. In the proposed model I am
using HVAC System type Water Loop Heat Pump. I am trying to be consistent
with the way I entered the fan power for the baseline - in kw/cfm - but the
box for that is greyed out in the system level spreadsheet for Fans- Fan
Power and in the Zone Level for Zone Fan kW/flow (kW/cfm).

I entered the cooling efficiency for these units as EER so I assume I have
to break out the fan power.

Can anyone help?

Thanks in advance.

Gerry Hazel

Gerard Hazel's picture
Joined: 2011-09-30
Reputation: 0

I have a 725 ton chiller with full load efficiency (primary efficiency =
.546 kw/ton)

and part load efficiency (NPLV = .464 kw/ton). What are peoples experience

choosing whether to utilize eQUEST's own built-in chiller curves versus

their own custom curves? Are there any rules of thumb as to when the later

appropriate (because otherwise you are not getting the energy savings under

part load conditions)?


Account Deleted's picture
Joined: 2011-09-30
Reputation: 0


To allow access to the System kW/cfm field, select "Restore Default" in
the "Static in WG" field first. For zone kW/cfm, I don't think zone fan
power is appropriate unless you are trying to model powered induction
unit boxes or some equivalent.



Bishop, Bill2's picture
Joined: 2011-09-30
Reputation: 0

My general rule of thumb is that if I want to show a quick comparison of standard technology, for example variable speed chiller vs constant speed chiller, or the chiller is basically a place holder in the model and not important for whatever I am looking at, or I can't get the info from the manufacturer, I use default curves. If I want to compare a turbocore machine vs variable speed screw vs variable speed centrifugal, or Carrier model XXX vs York model XXX, I use custom curves. If you want to use custom curves and haven't done it before, I would recommend downloading the chiller curve document written by Steve Gates and my spreadsheet from the following link:



Jeremy McClanathan, P.E., BEMP, HFDP, LEED(r) AP BD+C

Jeremy McClanathan's picture
Joined: 2011-09-30
Reputation: 200