Multiple HVAC systems in a single zone

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To all the knowledgeable eQuest users,

I am working on a design for an institutional building. Each room in the
building is its own zone. The rooms will have in floor heating connected
to a geothermal loop as well as a forced air system which will primarily
provide the required ventilation, but also heating from a supplemental
gas boiler. The core of the building will only be serviced by the forced
air system. I believe this can be done in eQUEST but I am not sure how.
The main question, is it possible to define two HVAC systems for a
single zone? Two possible operation models, one system operates at
certain times of the day, the other works at different times of the day.
The other operation model is one system works up to a certain percentage
of the requirement, and the second system meets the remaining demand. I
believe "equipment controls" can handle this, but I'm not sure how to
set it up.


Rishi Poddar

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Joined: 2011-09-30
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In general, eQuest (DOE-2) cannot model two systems in one space,
regardless if they ran at serrate times. I was thinking you could
perform the ventilation with gas boiler heat by a Unit Ventilator
(allows outside air introduction), then try the floor heating with
baseboard radiation (baseboards are allowed in many systems). However,
you cannot assign any geothermal source to baseboard heating. You MAY
want to make the baseboards electric in the model, then somehow
translate the needed load for this system into what the geothermal can
contribute, and what it can't.

John R. Aulbach, PE, CEM

Aulbach, John's picture
Joined: 2011-09-30
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