[Hap-users] Hap-users Digest, Vol 53, Issue 3

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I'd recommend contacting Carrier software support - I find them to be pretty

That being said, I don't think HAP can model wrap-around coils and it can't
model outdoor air from another system. Here are my suggestions but they may
not be of much help:

As a work-around to allow you to model the rooftop AHU conditioning outdoor
air, you could model the floor level AHUs without any outdoor air (in each
space, select OA ventilation requirements as "user defined" then enter "0").
Then model a separate AHU with all of the building's outdoor air (you'll
need to create a dummy space for it and enter all of the building's outdoor
airflow into this space). This may work ok if you are supplying neutral
temperature outdoor air to the floors but if not; you'll probably want to
incorporate the rooftop AHU fan power and coil capacities into the floor

As for the free reheat you are getting from the wrap around coil, I see that
v4.9 has a heat recovery chiller - that may be the best way to simulate it.
I haven't installed v4.9 yet so I'm not familiar with how that works but I
don't think you would want to have that chiller serve the floor level AHUs
as it would make too much free heat recovery available to the whole building
- you probably only want to use this if you choose to model a separate
rooftop AHU as you could have your heat recovery chiller only serve that


Aaron Smith, P.Eng
M&R Engineering

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Joined: 2011-09-30
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