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Design load with sizing factor is lower than Calculated design load [closed]

asked 2018-06-19 00:59:47 -0500

Saroop's avatar

updated 2018-06-19 10:39:22 -0500

My Design Load With Sizing Factor is 33.14 tons which is lower than my Calculated Design Load of 48.69 tons. I didn't input a sizing factor for my zones so it should be using a default value of 1.15, correct? Why is this lower than the calculated design load? The air flows have a similar trend.

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Closed for the following reason the question is answered, right answer was accepted by Saroop
close date 2018-06-19 11:06:58.832386

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answered 2018-06-19 02:45:00 -0500

No, if blank or zero, the Zone Cooling (heating) Sizing Factor will be replaced by the global Sizing:Parameters.

By default the Sizing:Parameters sizing factors are 1.25 for heating and 1.15 for cooling (corresponding to ASHRAE Appendix G), but you may have changed them. These can be viewed/set on the "Simulation Settings" tab:

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Thanks for the response. I didn't change the sizing factors in simulation settings, so they are using those values. 1.25 for heating and 1.15 for cooling. I now realized that I input a Cooling Design Air Flow Rate and that value is being for the sizing factor calculations.

Saroop's avatar Saroop  ( 2018-06-19 11:06:13 -0500 )edit

Ok glad you figured it out!

Julien Marrec's avatar Julien Marrec  ( 2018-06-19 13:46:02 -0500 )edit

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Asked: 2018-06-19 00:59:47 -0500

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Last updated: Jun 19 '18