Dear fellow eQuest users,
I am currently solving a system which uses humidistat (coil for
dehumidification and steam loop for humidification).
I have got absurd results in 'hourly reports'. I have chosen a series called
'Moisture added or removed from air for (de)humidification (lb H2O/ lb dry
air)' under 'HVAC system' .
In the results I have got most hours with very large values, as high as 144
lb H2O/lb dry air. The system uses DOE weather data and is recirculation
type with minimum outside air. Is this a bug or am I reading something
incorrectly?
Thanks in advance.
Regards,
Kalpesh
Kalpesh,
I noticed a similar problem when I was doing a dehumidification study recently. I am convinced the hourly report simply has the units wrong, and it should simply be lbs H20 (not per lb dry air). I don't know much about your building or climate conditions, but 144 lbs (~18 gal) could be a reasonable lbs/hr dehumidification load for a sufficiently large building with high latent loads and/or a humid climate. Not certain, but it's a possibility.
A way to verify this would be to use a combination of other hourly reports to arrive at the humidification load (you have cfm and humidity ratios for the various air streams).
Cheers,
Ari
Ari Greenberg, LEED AP BD+C
[cid:image001.png at 01CFA272.DC1B1E90]
100 Cambridge St., Suite 1400
Boston, Massachusetts 02114
T 617.517.6224 * M 857.231.1076
cannondesign.com
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It is lbs of water, NOT lb(water)/lb(dry air).
I've done the hand calculations using outside air conditions (temp, RH, etc.) from the weather file and coil outlet set point conditions to confirm.
The hourly report number is correct, just not the units associated with it.
Fred
Fred Betz PhD., LEED AP (r)BD&C
Senior Sustainable
Systems Analyst
AEI | AFFILIATED ENGINEERS, INC.
5802 Research Park Blvd. | Madison, WI 53719
P: 608.236.1175 | F: 608.238.2614 | www.aeieng.com
fbetz at aeieng.com