Want to check my chimney draft on both my chimney's... See you can buy them on Ebay . Any good verses bad units.. I see you can get basic mechanical ones for under 20 dollars..
Not my first thought when I read manometer. Curious as to why the flow needs to be measured. It either drafts or it doesn't right?
Depending on your set up it is possible to have an over draft situation. This can lead to short burn times and possible over firing of stove. Most appliances have a spec range for proper draft. Correction can be accomplished with a barometric damper or simply restricting the flue. Draft is a funny thing though as it is sensitive to ambient conditions. It will vary during the course of a burn, hence the use of the barometric damper. I have never seen one for double or triple wall flues though. The simplest method is a manual damper in the flue which is nothing more than a plate on a spindle passing through the flue pipe. A lot of times over draft can be caused by high winds blowing over exit of flue pipe when terminated in the simple wire mesh and top hat. The wind creates a vacuum that literately sucks the exhaust gases out. Using a flue termination that breaks the air flow over the flue exit most times will resolve this type of issue.
I though barometric damper was a major no-no for a wood flue because the excess cold air introduced accelerates creosote buildup. Key damper a better option?
I added 4 feet of chimney to my Esse cookstove this year , wanted to see if I'm in the specs they call for out of curiosity... They actually supplie an insulated pad that goes into a removal plate on the stove top chimney flange,, you poke a hole through the pad and insert your manometer tube... Having a proper draft according to the stove specs will allow for the best function of the cookstove.. Then I'd be curious as to the draft of my 21 foot chimney on my Progress Hybrid... That thing really has a good draft and just want to make sure it's not too much... I can hold a match up inside the PH to the intake screen when it's stone cold , blow the match out and it sucks the smoke up like nothing... I remember reading as to some people having smoke out the door issues when loading,,,, not me at all... So I was just curious to see if I have ideal drafts on both my chimney set ups... too much or just where they are...
Baro damper, yes it is/ will, which is why , most likely, that it is not available for double and triple wall flues, more for the oil/coal burners. Key damper is option, makes for a pain cleaning up or down depending which way you start from. I will guess that at the competition in Washington that you will find some creative ways of addressing automatic/manual adjustable draft systems particularly on non-electrified stoves as well as systems utilizing electronic monitor/ adjustment. An Overdraft condition can cause a particulate emission rise.
We use Magnehelics in the Pellet world. Some Manuf tell you the exact measurement to shoot for in Draft (inches of water). Most are in the neighborhood of .15, but that would be very excessive in a wood eater. I would imagine some Wood stove manufacturers would have the number? Maybe a simple call could yield the numbers your searching for? As for the use of a Baro Damper? I wouldn't suggest it on a wood burner. Has it been done? Yes. Will it cause an excess of Gunk to build up? Yes.
Ouch, Education hurts my head. I had to look up magnehelic. Looks much easier to use than my old ( as in very) manometer unit. Reading the specs of one company, One would need to due some digging to find the right type for hot flue gas use beyond what I saw on that sight ( 140f limit high end). There was a NG option. But I really did not dig any further.
No need for a high temp Magnehelic. They "suck" from the unit. You just need to connect a small 1/4" hose and make a fitting where your gonna draw from. A small barb will need to be put in somewhere. The air is being sucked from the Mag, not blown into it. Plus, it only takes a minute to test. Once the fire is going good. If I were to donit? I would want to test at start up, and also after about an hour into a good burn with stove top over 500°-600° (steel stove). But given all the varibles (outside temp, wind, pressure, etc) the numbers could chamge drastically over a months time.
