Circulation loop pumps/AC fans

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Hi All,

I'm trying to learn eQuest (v3.6), and I've run into a bit of a wall.

I'm modeling a small building (2,000 sqft) in a cold climate. It's naturally ventilated in the summer, though I'm modeling it with A/C for Appendix G purposes.

The heating system is a radiant floor hydronic system with two zones. I've set it up as 2 secondary circulation loops with baseboards that run off a primary circ loop with a boiler. I'm having two problems:

1)The pumps for the 2 secondary loops run at 90+ flow, rpm and elec for all 8760 hours. They're variable speed, and autosized (I've entered the head loss for the loops per the engineer's calc). The boiler runs for 4,258 hours. In report PS-D, the heat supplied has hours in all the ranges from 0-100%, and total hours are about 1/2 the pump hours

2)The larger zone (55% of sqft) has 568 underheated hours (SS-R) and the smaller one (45%) has 191. Changing several variables of the system (delta T, flow, etc) only changes each of these +/- a few hours. On report PS-D, total heat run hours for the bigger zone is 3881, the smaller zone is 4943. Any suggestions on what could be limiting heat getting to the zones? Is there a schedule that I'm missing or misunderstanding?

For cooling, I'm having difficulty getting the fans to only run when the A/C is on. Left without a schedule, they run all the time. I created a schedule to limit them to summer when the building is open, but they're on all the time within those two parameters.

I hope I've given enough info to give insight into the problems, and hopefully they're not so general as to prevent useful suggestions. Any help is greatly appreciated.


Shane Mannion's picture
Joined: 2011-09-30
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