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I would like to here people's opinion on the best approach to a particular

I have a model where the staircase is open and three stories tall, but there
is two fan coil units, on the first and third floors. Is it better to model
this as two spaces or as three spaces?

rdh4176's picture
Joined: 2011-02-14
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I usually model staircases as one space/zone per floor. Doing this, you
have (at least) two options for modeling the fan coils. 1.) You could
enter them as designed on the first and third floors, and turn the floor
surfaces on the second and third floors to "air" construction. 2.) You
can put fan coils on all three floors and divide the total capacity by
three. I think option 1.) is more realistic but may result in unmet
heating hours on the second floor. Option 2.) is a little quicker but I
wonder how accurate the fan energy will be if you don't prorate the
static pressure. I also reduce my DESIGN-HEAT-T in stairwells and
mechanical spaces, and apply a different thermostat schedule with a
lower heating setpoint.


William Bishop, EIT, LEED(r) AP

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