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The Heat-Kit Bakeoven Option

New design optimizes performance

Bakeovens are readily incorporated into Contraflow heaters, and have become a very popular option in the last few years. There are two types. In the traditional "black" oven, flames pass directly through the oven, which is then ready to bake after the fire is out.

In the "white" oven design that we have developed for the Heat-Kit, the flames go around the oven chamber instead of through it. This allows the oven to be used at any time. The oven floor is unobstructed, with no throat opening to the firebox, and the interior remains clean, with no soot or ash deposits. The sealed oven chamber and airtight cast iron/glass oven door gives you perfect bread crust - you don't have to add any moisture.

The design has been refined over several years of trials and feedback from users . It is no longer simply an add-on feature - instead, we have redesigned the whole heater around it.

Benefits include:

  • oven floor is several inches lower, for easier access
  • oven temperature now reaches up to 500 F., and will stay above 350 for up to ten hours (see chart below from lab test - wood load for this test was 42 lb., previous fire was 24 hr.)
  • we've added direct heat to the oven floor, so that you can now make the ultimate brick oven pizza. The oven operates for zero cost, since you are firing the heater daily to heat your home.
  • It can be on either side (front or back). A popular design is to have the heater serve as a space divider between living room and kitchen, with the glass firebox doors on the living room side and the oven on the kitchen side.

(Below): Graph of oven and oven floor temperature over time from test at Lopez Labs. Wood load was 42 lb. Douglas Fir and previous fire was 24 hrs. Note that oven temperature peaks about 2 hours after lighting the fire.

Oven Temperature ChartThe standard oven holds 4 loaves of bread, and the new larger oven (optional on the Heat-Kit-22) holds 5 loaves per batch. Three batches of bread per firing is a typical capacity. Gourmet cooks will really appreciate the oven's finer points. A great feature of masonry (retained heat) ovens is a very even temperature. It will bake perfect bread over a wide temperature range. The same applies to roasting poultry, fish or meats - because the oven starts hot and then slowly cools, it is much more forgiving . Whether you are serious about cooking or more casual, we believe that this is the best oven available today.

Exploded bakeoven

Test Data

1996 Christmas Test Data
1997 Lopez Labs Test Data

Christmas 1996 Test Data

We've been using the oven at our house (photo at top of page) over the holidays, and have gathered some data, below.

December 23:

The heater was fired at 7:00 a.m. About 35 lbs of hardwood had been stacked in the firebox 8 hrs previously. Because the wood was surface dried, the fire took off very quickly. Here is a record of the oven coming up to temperature:

We stopped tracking temperatures at this point, and started baking. Our house guest was baker Anna Nulty, formerly of Terra Breads in Vancouver, and now working at Little Stream Bakery in Perth, Ontario. The goodies were as follows:

Load 1: 3 loaves whole wheat sourdough bread
Load 2: 2 loaves whole wheat yeasted bread
Load 3: 1 pizza
Load 4: another pizza
Load 5: a tray of lemon-cranberry-almond biscotti
Load 6: a tray of almond-chocolate biscotti

In order to bake 6 loads, we added another 25 lbs of wood once the first firebox load was down to coals.

December 24: No fire (weather was warm)

On December 25, the previous fire in the heater had been 48 hours. We stacked wood in the warm firebox about 10 hrs. prior to burning. This dried the surface, so that the fire was very fast to take off. We used 35 - 40 lbs of hardwood. The fire was lit at 8:30 a.m., and at 9:15 we added a large log that we wanted to get rid of. We put the Christmas turkey in a clay baker and put it in the oven at 11:15 (note the temperature drop on the graph below). The turkey came out of the oven at 2:45 p.m., roasted to perfection.

bakeoven temperature graph

December 26: We loaded the heater with about 50 lbs. of hardwood, brought in from outside. No baking (too busy eating). Here's the temperature record:

December 27: No fire today. Stacked cool firebox with about 40 lbs of large hardwood (6 pc) at 5:30 p.m.

December 28: Lit heater at 2:20 p.m.. Oven is at 90F.

At 5:25 p.m. we stopped tracking temperature and put in a pan of sourdough dinner rolls. Note that the oven only got up to 375, because the heater had not been fired for 48+ hours. The rolls, which went in a bit late, took a little longer to bake, and came out at 6:10 - they were delicious. A second batch went in at 6:10, came out at 6:45, and then a lemon-millet biscotti went in.

December 29: No fire today. At 6:45 p.m., oven is at 120F.

December 30: Stacked 60 lbs wood in heater and lit at 11:15 a.m. Outside temperature -15C (1F) Oven is at 90F.

At 4:40 p.m. a casserole and a squash went in. Note the temperature dip in the graph below. At 5:50 p.m., the few remaining coals were stirred, and 10 lbs of small wood (10 pieces) were added to bring the oven back up to temperature for baking whole wheat sourdough rolls:

December 31: 9:00a.m. Oven is at 185. The heater was fired with 45 lbs. wood. At 12:45, the coals were raked and 3 large pieces were added.

January 1: 8:00 a.m. Oven is at 170. Outside temperature is -5F.

1997 Lopez Labs Test Data

January 18: 10:30 a.m.

We've switched to an infrared thermometer which gives instantaneous surface temperatures with a simple "point and shoot" operation. The graph below shows surface temperature readings for the oven floor, back, ceiling and side. It's -25C outdoors, so we're firing the heater with about 70 lbs. of wood. The last time it was fired was yesterday morning.

February 3, 2003

Visit Lopez Labs
1996 Christmas Test Data

Heat-Kit Gallery Library The Brick Bake Oven Page - most popular spot on this site Brick Oven Page


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This page last updated on May 26, 2007

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