Need help explaining a couple of error messages

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I'd be very appreciative is someone could shed some light on a couple of
errors that getting in eQuest. The system I'm modeling is a "power
induction unit". I'm using eQuest version 3.63, build 6359.

General notes concerning the model in question:

1) The model I'm running is of an elementary school Houston, TX.

2) The building has a lower than normal sensible cooling load which is
resulting in a very high percentage of OA (extremely high percentage at
low load conditions).

3) I don't have pre-heat or heating coils defined but when I review an
hourly report I can see that an electric heating source is being added

4) I've defined my coiling coil leaving air temperature as 55F. Even
with cooling control set to constant, leaving air temperatures rise to
65F. Would the high percentage of OA cause this?

7) Per the hourly report I can see that the unit is heating and cooling
at the same time but I don't know how to stop that from occurring.

8) This is for a LEED base line model, so I do not have an economizer
installed, (not that it would help much in Houston).

*Error #1 - This error appears only in the QC Details below 4) Hours of

Fan vs. Occupancy Hours: The average hours of occupied light operation
/ fan operation ration for the building is 21.73 and appears high (error
above 1.75, see PS-E & SS-C reports).

I don't understand what the error is, what values are used to calculate
the ratio and how the ratio & the PS-E & SS-C play into the error.

*Error #2 - This error shows up both in the "REPORT- ATTN" error log of
the "Simulation Output" and the QC Details 5) HVAC Equipment
Descriptions under the tools menu:

In curve: Variable Speed Drive FPLR the dependant value

Is exceeding the limits

Value/Min/Max/First time: 1.257 / 0.100 / 1.000 / 12.31.24

If I'm reading this error correctly the output on my VFD is going above
1. What I find odd is that the 1st time the error is exceeded is on the
very last day and hour of the year. Seems odd that I would only get
this error on the last hour of the simulation.

*Error #3 - This error appears only under the QC Details below 7) HVAC
Load & Performance Results:

Cooling Coil Loads:

System "1st VAV Unit has a high Winter/Sumer cooling coil load ratio of
0.67 (error over 0.25, see SS-D report).

*Error #4 - This error appears only under the QC Details below 7) HVAC
Load & Performance Results:

Reheat Loads:

System '1st VAV Unit' Coincident Cool & Heat / Heat hr ratio of 0.76 is
unusually high (error if > 0.50, see SS-C report).

Any help is appreciated, thank you very much!

Mark R. Seibert, PE, LEED AP

Mark Seibert's picture
Joined: 2011-09-30
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