Direct vent vs Power vent...

[davemich]

...what is the difference and the advantages of each?

[lime4x4]

Most people use them for when they have no chimney or are a placing a stove that can use either in a location without a chimney..example some reading and leisure line coal stoves can either be vented into a chimney or they can use a power vent to vent the exhuast to the outside
Direct vent vents directly to the outside no chimney required plus there not designed to vent into a chimney. the harman dvc-500 is a direct vent coal stove it vents directly to the outside thru a wall and it also takes in outside air for combustion

[hgmd1]

I believe that there are 2 diffent systems. One is positive pressure out of the stove ( direct vent). The other is a negative pressure pulled to the outside wall. I don't know the advantages and disadvantages of each. I know that the leisureline uses a SWG system that applies negative pressure from the outside. Perhaps some else can explain it better.

[AL-53]

Dave...

I believe the direct vent is used when no chimney is available it is a though the wall install....


power venting

..The heat is transferred through the heat exchanger and distributed to the conditioned room. The products of combustion, however, must be vented safely out of the structure. In a conventional chimney, venting is achieved by the natural lifting action of the hot combustion gas. New, efficient systems absorb more of the heat in the heat exchanger and produce lower temperature vent gas. Lower temperature gas does not rise as quickly or as reliably as in older, less efficient systems. A power venter uses a motorized blower to vent the products of combustion. A power venter is interlocked with the appliance to ensure that proper draft is achieved.

this was taken from the Leisure Line stove page

hope this helps....If i am wrong some one correct me....

Al

[davemich]

Then there are 2 types of direct venting...1 is just the venting of combustion out of a 4 inch pipe and 2 is venting out and pulling air back in through the same outlet...inside lining of pipe is for outflow and perimeter of pipe is for air return into the firebox. Is this correct? You cleared up in my mind what power venting is used for. Do all stokers have power venting??

[AL-53]

dave....here is some diagrams of both

http://www.alaskastove.com/direct_vent.htm

http://www.alaskastove.com/power_venter.htm

looking at the diagrams..I believe one is for top vent..other is for back venting....

I hope this clears up things...if not..i will try to get you better info

Al

[lime4x4]

not all stokers are designed to use a power vent..the harman magnum stoker doesn't and isn't designed for a power vent..Well not safely anyways..All the stokers that i've seen that uses power venting have a device attached to the stove body which i assume measures pressure inside the fire box.So that if the power vent fails it will shut off the stove

[WNY]

Our Keystoker has the Direct Vent, it is a blower housing on the back/bottom of the stove, the 4" pipe extends thru the wall with a 6" collar around it (to keep it cool) and a Tee and cap. That is it. If you need pic let me know.

ALSO, our stove was designed for a direct vent, we ordered it that way, it vents out the Bottom back of the stove, so all the heat stay in the top of the stove. It cannot be used any other way as far as I know.

Also, makes it easier to fill the hopper, no top pipes.

[davemich]

Dave, could you submit a pic?? Would like to see what it looks like...Dave

[WNY]

DaveMich
Here you go.
You can see the cast iron tube at the bottom and the blower is on the opposite side, the outside just has a tee and cap. You have an access panel in the forground for cleaning it out, it does build up with ash and I have cleaned it out 2x so far. Just unplug the stove, remove cover, vacuum it out, plug it back in.

Also, on the other side is a separate flu switch, if the blower stops or clogs up, it will shut the stove down.

[oilman]

The definition of power vented vs. direct vent is the same whether a coal stove, oil or gas unit.
A power venter is using a mechanical draft device (power venter) to put the combustion zone under a negative pressure to exhaust flue gasses.
A direct vent is using the burner's fan to create a positive pressure in the combustion zone to exhaust the gasses. Direct vents are also a "balanced flue"- in other words, they have an air intake and exhaust. Commonly a concentric flue terminal. Exhaust in the center, combustion air in the outer pipe.

[davemich]

Thanks for the input guys...Oilman...you summed it up for me in that last post. Appreciate it...Dave

[WNY]

No problem.
Ours draws air from the room thru the little square plate on the side of the blower and a small hole where the flue switch is. There is an adjustment for draft on the direct vent blower, just a plate that slides to increase/decrease the fan suction inside the unit. You have to hook a draft gauge up to the small hole in the ash pan door to check.