Description of first try at Barra Box...
Changes in Change Package A...
The two plots below show the results for the first 3 days after putting in the Change Package A changes.
The one that is marked just "Temp F" is the ambient outside temperature.
Bottles South is the first row of bottles, Bottles North is the last row of bottles.
The "Col In" is now up near the collector inlet duct entrance -- just down stream of the back draft damper.
The added outside insulation was NOT on yet for these plots -- I just added it today (Jan 19). So, this is same insulation levels as the original box.
The fan was not hooked up for these plots -- the thermostat on the fan was not working, so I disconnected the fan altogether. I replaced the thermostat today (Jan 19), and plugged it in, but see note about the fan below.
Note on fan: When I checked the fan after putting the new thermostat in, found it was blowing air up from room into bottle area. At first I thought this to be a mistake, but after thinking about it a minute, decided to leave it that way -- logic being that if it blows air from bottle area into the room, it will also blow air through the backdraft damper (since this is the normal flow direction) -- at night this will result in room air blowing past the glazing and then back into the bottle area. With fan blowing air from room to bottle area, it seems like it may close the backdraft damper (I'll check on this when the fan starts running). And, it should also circulate room air past the bottles and back into the room via the slot at the north end of the bottle shelf?
Closer view of the middle day from plot above.
I've had a chance to watch the back draft damper both during the collection period and at night, and it seems to be doing the job. It opens to about 45 degrees in full sun, and the Vane Meter reads about 50 fpm. At night it sucks tight against the hardware cloth backing. I'm sure there is still a bit of leakage around the edges, but I think it seals pretty well.
Gary January 15, 2010