Florida Bungalow Syndrome Comments

[DriftWood]

Just read the article in the title by John Gulland.

Just to comment and perhaps start a dialog, please don't modify your air control or change your stove any way to remedy this problem. I really have a hard time agreeing with anyone that suggests this is a solution. I know manufacturers often say do not install barometric or flue dampers or flue top restrictions, BUT please consider using a damper before you consider modifying the air control system of the stove.

Modifying your stove can cause a long list of issues, but the most important one to mention is that the warranty will be voided if this modification is found.

NOT MY WORDS

Part of a Reply to a email sent to Mr. Gulland.

"The fact is, my proposal would have absolutely no effect on appliance design or performance on short chimneys. It is a simple proposal that air controls be allowed to turn down low enough to control the appliance"

Regards,
John
Gulland Associates Inc."

You could reply to him by email or phone found at
http://www.gulland.ca/

 

[precaud]

Part of a Reply to a email sent to Mr. Gulland.

"The fact is, my proposal would have absolutely no effect on appliance design or performance on short chimneys. It is a simple proposal that air controls be allowed to turn down low enough to control the appliance"

I totally agree with JG.

 

[Highbeam]

I burned 100% dry red cedar earlier this year. 1.5 cords worth in my EPA hearthstone and it is controllable. Of course mine was cut as cordwood and not mill ends which may be relatively small. Don't fear a new stove because of red cedar, the cedar is denser than other woods out here such as cottonwood which I am now purely burning and it is controllable and quite pleasant in our climate.

To this thread: I wouldn't modify the stove either unless an actual overfire condition could not be controlled with a flue damper. An intake damper would be better for an efficiently sucking chimney and to avoid the creosote and sweeping issues that the inline damper produces. That said, if there was a simple set screw that controlled the bottom setting of the primary air control I would be tempted to adjust it if an overfire conditino existed.

 

[swestall]

In an emergency you can plug off the air input on most stoves (ex PE they do it automatically) and stop a run away; that is if you are there and paying attention.

I am with Corie on using a draft damper in the pipe. I don't have one this year but am going to install one when I clean at the end of the season.

I have expereinced the runaway twice with the Mansfield from Hearthstone. Both times the secondaries were burning like mad and the coal bed was very well established; and it was below 20 degrees outside. Both times I used my leather work gloves to plug off the air input for the secondaries and that immediately killed the runaway. I let the stack temp fall off and then pulled the plugs (folded glove thumbs) and all resumed to a normal burn. The larger question is what happens when you are not there to observe the problem. In that case, the stove overfires and hopefully you don't have a creosote build up to cause a fire nor does your stove get ruined. This latter condition makes the case for some type of mandatory shut down mechanism when flue temps exceed an over firing conditon.

Now, most of us are old enough to know that we should not hold our breath for such an innovation on an industry wide basis. In the meantime, find out where your secondary input is, take a look and see if your primary is all the way shut down when your damper is fully closed and the stove is set to draw maximum secondary air and finally figure out a safe way to quickly shut the secondary air input down if you do indeed get a runaway fire at any point: better safe than sorry.

 

[tradergordo]

I'm still waiting for someone to explain why a flue damper is better than a secondary air damper. The last two posters have said this, Corrie says this, all I'd like is a simple explanation as to why.

To quote Gulland from the article:
"Even when a [flue] damper is open, it represents a significant restriction in the flue pipe, especially after it collects a coating of deposits. In a six inch flue pipe, a key damper could effectively block 15 to 20 percent of the flow area. In very tall systems, high draft might be able to overcome this resistance, but in marginal situations, such as that of a 25 foot system operating in mild fall weather, for example, a key damper could contribute to smoke roll-out when the door is opened for loading. Furthermore, in a study done for Canada Mortgage and Housing Corporation some years ago, it was shown that appliances with key dampers or by-pass dampers are more likely to be implicated in open door smoke spillage, if only because users either forget to open the damper first, or because the damper doesn’t fully open. Flue pipe key dampers are a throwback to earlier and less appealing forms of wood heating and in an ideal world they would be relegated to the history books."

In addition to that, they also have to be removed for chimney cleaning which adds one more step to that process (maybe not a big deal but worth mentioning).

And to avoid further confusion or misrepresentation of what Gulland proposed, here it is:

"...whatever option the dealer or installer chooses, he or she could be open to criticism. Here are a few recommendations that might help to resolve this problem over a period of time.

1) The EPA and the committee responsible for the CSA B415 standard (which has the same problems) should acknowledge that when stoves are optimized to operate under test conditions, they do not perform as intended when connected to tall chimneys and in cold climates.

2) When designing new stoves or reworking existing models, manufacturers should develop air controls with a means of adjustment to deal with this problem. Such adjustments should not be readily accessible to the stove user.

3) Stove manufacturers and regulators responsible for wood stove emissions should consider it acceptable for a WETT certified technician (and the U.S. equivalent) to make air control adjustments when they encounter short burn times with stoves connected to tall, straight venting systems. "

 

[begreen]

Could it be that it just makes it harder for the stove to pass EPA testing? I could also see a secondary damper confusing people and being left open/closed inadvertently. The trend seems to be keeping things simple for average users.

As to the concerns with a key damper, well of course if one leaves it closed smoke will spill out of the door when reloading. It is a good reminder for a dope slap on the head. A secondary damper will give the user less indication of it being in the wrong position unless the user is attentive.

 

[tradergordo]

Could it be that it just makes it harder for the stove to pass EPA testing?

Not only harder, but maybe impossible. Did any of you guys actually read the article?? The point was that the EPA and stove manufacturers need to come together to address the problem, the manufacturers can't do this without EPA support.

I could also see a secondary damper confusing people and being left open/closed inadvertently. The trend seems to be keeping things simple for average users.

Well Gulland doesn't think the air control "adjustment" should be "user accessible" - I'm not sure I agree with him there, and I think his idea would only work for certain specific stove designs. But either way, how is accidentally closing a secondary air damper any different from accidentally closing a flue damper???

As to the concerns with a key damper, well of course if one leaves it closed smoke will sill out of the door when reloading. It is a good reminder for a dope slap on the head. A secondary damper will give the user less indication of it being in the wrong position unless the user is attentive.

I agree with you in the case of a cold start for example, but what if you are just reloading on a good bed of coals? Maybe you won't touch the secondary damper because its already in a good position, but you'd have to open the flue damper to prevent "smoke in your face". I don't think this is really a critical issue though, people would eventually learn to do it right after screwing up enough times.

 

[begreen]

John was specifically addressing the high-draft situation where a stove was hard to control even with primary air fully closed. In that case I agree that a fixed setting for secondary air restriction would be fine. Personally I would want secondary control accessible for other benefits like reducing airflow when in the coaling stage (past secondary burn). But I am not sure this would be the best for the general user. I think that you and most folks on the forum are more attentive and aware of their fires. Think about how many people used to space out pushing in a manual choke on their cars (dating myself here). Don't underestimate the thickness of a human skull.