Oak vs Base Burner

Hello Everyone
Can anyone tell me how much more efficient a base burner is than an oak stove of the same size? Have any of you who own a base burner ever done a coal consumption comparison between direct draft mode and base burner mode?
Id be REALLY interested in hearing how much more efficient base burners or even stoves with just indirect back pipes are than a straight oak stove.

It depends on the Oak stove and the quality thereof. Oak stoves run the gambit from very cheap to extremely expensive and high quality. I've never seen a base heater made in an economy model. They were always a lot more expensive than other types of stoves. That being said, a good oak stove such as a Florence Hot Blast, or a Hearld Oak for example that is direct draft would run around 70% overall. The advantage to Oak stoves is that they are designed to be multi fuel. You can burn either type of coal in them or wood. Base Heaters on the other hand are in most part specifically made to use Anthracite as the only fuel. There are exceptions such as my No 6 which is a dual fuel stove. The Glenwood No 9 I have is an Anthracite only stove. It is perhaps the best possible design for burning Anthracite as they designed the stove to take advantage of the combustion characteristics of that fuel. I did a test with my Glenwood No 9 running it in both direct draft and then base burner mode to observe the differance. I will put up the link here so you can read it.

http://nepacrossroads.com/about20716-105.html

As you can see from reading the thread; the stove when in base burner mode operated at a far greater efficiency than direct draft. Even so I would not look down my nose at a high end oak stove such as an Andes Oak with an indirect back pipe along with the double heater option. A good direct draft oak stove would still be way ahead of a current box design since you have the correct proportions for good combustion and a much larger radiant surface exposure.

PJT wrote:Hello Everyone
Can anyone tell me how much more efficient a base burner is than an oak stove of the same size? Have any of you who own a base burner ever done a coal consumption comparison between direct draft mode and base burner mode?
Id be REALLY interested in hearing how much more efficient base burners or even stoves with just indirect back pipes are than a straight oak stove.

I agree that it depends on the stove. A good oak stove with an indirect back pipe is going to hang in there with the "same sized" base heater. I would think it would be a matter of a few percent efficiency. They are doing the same thing primarily (elongating the flame path). The base heater having the longer flame path would be slightly better. The base burner, on the other hand, (anthracite only) is just an excellent design of simplicity with the suspended firepot and fewer moving parts that really works.

We also have to consider firing rate. At a modest firing rate the Oak stove will not have a stack temperature that is excessive, but as firing rate is increased, stack temperature will rise. The extra heat absorbing surface of the extended flue path of the base heater will modify this and efficiency will remain high over a wider range. It will have a higher output with modest stack temperature in a stove very little bigger than the plain Oak.

The design with the fully enclosed fire pot will also benefit from the higher temperatures in that combustion chamber which in turn will require less air, which in turn will lower stack temperature.

franco b wrote:We also have to consider firing rate. At a modest firing rate the Oak stove will not have a stack temperature that is excessive, but as firing rate is increased, stack temperature will rise. The extra heat absorbing surface of the extended flue path of the base heater will modify this and efficiency will remain high over a wider range. It will have a higher output with modest stack temperature in a stove very little bigger than the plain Oak.

The design with the fully enclosed fire pot will also benefit from the higher temperatures in that combustion chamber which in turn will require less air, which in turn will lower stack temperature.

I agree. A good quality Oak stove will do just fine at a moderate firing rate. If you read about my little test with the Glenwood No 9, I ran it at a high firing rate to see what would happen. Needless to say it passed with flying colors. For Bituminous a Hotblast Oak such as a Germer, Florence or other similar model would be very hard to beat.