eQuest - Heating/Cooling Loads

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Hi all,

I'm not sure I understand how eQuest calculates the heating/cooling
equipment loads.

I've built two models with identical envelopes and internal loads etc,
and OA supply. In model A, we have a boiler and chiller on hot and
chilled water loops and a four-pipe fan coil air-side system. In model
B, we're using an air cooled Heat Pump and two-pipe fan coils.

In report PS-C for model A, the sum heat load is -29.6 MBTU, whereas for
model B, the sum heat load is -130.2 MBTU. I understand that the fuel
use should be very different, but I don't know why the load is so
different between the models. Shouldn't the heating energy delivered to
the spaces be the same in both cases? Why does the Heat Pump system
have a load that is so much higher than its counterpart?

Similarly, in report SS-E, January has 110 Heating load hours for Model
A, and 385 Heating load hours for Model B. Again, shouldn't the loads
be the same between the two models?

Thanks in advance for the help,

Katherine

Katherine Louman-Gardiner's picture
Joined: 2011-10-02
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