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Current Heater Testing at Lopez Labs

February 14, 1997

(9:30 a.m)

Our new technician, Clover Ardern, has done a baseline series of 20 test runs with fairly random wood loads on a 22" Heat-Kit heater with bakeoven.

Today, we did run 7 of a 10 run series with a controlled wood load. All pieces in a given run have the same moisture content, and are split from hardwood boles between 8" and 14" in diameter. The wood load consists of 8 pieces and 2 lb kindling. The pieces are stacked in a 2-3-3 log cabin configuration. The two top rows are stacked tight, with the bark down (see fuel load photo).

We used a Kodak DC-50 digital camera to document the burn progressions. Below are the images from today's test run, which finished at 11:00 a.m. Downloading the images from the camera, processing them, and uploading them to the server takes about 45 minutes.

For today's run, the wood had several percentage points more moisture than yesterday. Pieces were a little smaller. Efficiency was down a couple of points.

It is a little early yet to start drawing conclusions, but our basic thesis is that wood sizing and stacking has as large an influence on heater performance as any other factor, including heater brand. Compare today's photos and graph with yesterday, and the day before.

RUN No. HK-f27
Number of Pieces
Total Weight, lb
Wood Moisture %
Fuel Surfac/Vol


Average Stack Temp, F

+/- 0.1

Average O2 %

+/- 0.2

Stack Dilution Factor
g/kg CO
Combustion Efficiency %
Heat Transfer Efficiency %
Overall Efficiency %

+/- 1.5

Average Output, 24 hrs, Kw




Click on thumbnails below for larger image.
Click HERE for a continuous set of large images

2 minutes
Kindling has different arrangnement,
some pieces in front of pile, left to right
5 minutes
10 minutes
The top right piece has just rolled
over to the right.
15 minutes
1" air slot at bottom
of glass was closed after
this photograph
20 minutes 
Note the reduced flaming in the space
between the bottom two pieces. The kindling has burned,
and now there is greatly reduced reaction because the pieces
are too far apart. Note the reduced intensity of the fire in the
next frames.
25 minutes
30 minutes
40 minutes
50 minutes
60 minutes
70 minutes
80 minutes
90 minutes
100 minutes
110 minutes
120 minutes 

Compare with yesterday

0 minutes

This page last updated on April 8, 2003

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