[Equest-users] Fluid Cooler

[Ron Pecarina]

I am having a problem with a fluid cooler on a project.  The fluid cooler is
a closed circuit cooler that provides heat rejection for a heat pump loop.
I can get the model to run if I omit the heat exchanger which is integral to
the fluid cooler or if I provide a Wet Schedule, but delete the heat
exchanger.  I realize that neither one of these options will give me the
results that I truly need, but it sort of works for some comparative
purposes.  I have also tried this on 3.63 with the same results.

When I run either of the options identified above, I get the following
messages:

 **CAUTION********************
**************************************************
             In curve: FluidCooler-FluidCap-fRng&WB     the dependent value
             is exceeding the limits.
             Value/Min/Max/First time:          4.981
0.000          3.000   1/27/16
CURINV: No real root for CURVE:
 1  0.449745  0.027043 -0.000444 -0.028325  0.000285  0.001570

The CAUTION I can get around.  But the CURINV, which relates to the
FluidCooler-FluidCap-fAPP&WB performance curve, typically ends up as
thousands of lines in the output file.  I have yet been able to identify the
cause.

When I add the heat exchanger, the model crashes and I get the following
error:
 ***ERROR*********************
**************************************************
             Heat-Exchanger: FluidCooler-DryHX                has
inconsistent
             input parameters for flow calculations
                   Mode     SupTi     DemTi     DemTo
                      3     39.00     82.00     82.00

The values for SupTi, DemTi and DemTo will vary depending on other
parameters that I may change, but DemTi always equals DemTo.

I can provide the input and pd2 files if necessary, but hesitate due to size
and complexity of the building model, but it's what I have to deal with.

I also note that the pan losses/pan heater are not accounted for in the
model.  I am not sure if this feature is supported at this time or not.  The
unit has an electric pan heater, which I input.  I have tried both
defaulting the values and inputting the pan loss, but neither results in any
energy use for the heater.


-- 
Ron Pecarina, PE, CEM, LEED-AP
Energy and Sustainable Design Consultants, Inc.
1128 Noblewood Drive
Billings, MT   59101
406-208-0227
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