How much affect does flue caps have on draft? I have one stove that is hard to establish draft and another that has overdraft wonder if switching the caps would help
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Do flue caps affect draft much?
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A lot of difference when those silly bird screens plug up with creosote and ash. Hope you like climbing on your roof.
Mine has never clogged. But I would be digging out birds nests every year without one
Both caps are clean as far as build up I ran the soot eater up there before the season started. I have too much draft on the insert with the square top the other burns fine after draft is established. The round one has issues is establishing draft when the chimney is cold usually 30 or less outside.
round cap is 19'3" with a napoleon 1401
square is the 29'3" with a Lopi freedom
Lopi freedom is hard to control with dry wood
square is the 29'3" with a Lopi freedom
Lopi freedom is hard to control with dry wood
Well yeah with almost 30' it is going to be overdrafting neither of those caps will change that. And if you get one that restricts enough to reduce draft enough you would be cleaning it constantly. The 19' one should have plenty of draft
Here is a few videos of the Lopi
#1 all the way closed with foil tape 3/16" over the secondary plate
#2 open about 1/4"
#3 cut back all the way after being opened a little
When it cut back all the way the secondary inlet is open 3/16"x4.5"
#1 all the way closed with foil tape 3/16" over the secondary plate
#2 open about 1/4"
#3 cut back all the way after being opened a little
When it cut back all the way the secondary inlet is open 3/16"x4.5"
for overdraft a damper. based upon my testing some caps allow more draft compared to other caps.
i live in a windy area..my smoke is like a tail coming out of chimney...
for example rooster tail cap allows more draft than vacustack during a burn and wind...like .14 compare to .12 but i can dial this down with damper to almost .09.
vacustack is more stable on draft guage.. but need more time with the rooster tail during snow storms etc because one time the vacustack did back puff during heavy winds but it was in all fairness early in the first burn cycle ...not sure which one i will keep, but vacustack doesnt need grease.
have you measured the drafts?
they can change a bit depending on weather... but having too much draft can sometimes lead to a damper that only helps a little.
I definitely noticed a draft reduction after installing a SS cap . Actually made the stove more controllable. I would say its about the same as adding a 90deg elbow.
I have checked draft I added a key damper with the center covered but its been to warm here to have a fire, expecting some nicer weather tomorrow with the low around 30F so I am hoping to try it then.
The testing days are coming to an end for some....My draft today at 3pm was .08 but tonight it is .13 So I am using the key damper to get the draft down to .09 - .10. I dont like using the damper during the startup or 1st reload it seems like the flue temps drop a lot to 300 350.
I now have about 4 days of fulltime burning with the FAMCO tail cap. It has definitely increased the draft at burn. verse the vacu-stack. I dont need the increased draft but im hoping the cap will help with cold weather and low co readings.
I now have about 4 days of fulltime burning with the FAMCO tail cap. It has definitely increased the draft at burn. verse the vacu-stack. I dont need the increased draft but im hoping the cap will help with cold weather and low co readings.
cabinwarmer
Feeling the Heat
Good Day, I have a rather strong draft with my GM 60 stove. Flue is 6" - 11' DVL inside and 10' SS outside. If I wanted to reduce draft what manufacturer or type of caps should I begin to explore?
A key damper on the stove pipe would give you more control. They make one for DVL in a 6" section. Draft varies. On warmer days you may want that strong draft and run with the stovepipe damper open.
cabinwarmer
Feeling the Heat
Hello Gentleman, I am in need of replacing my cap anyway, was just asking. I have been influenced from this forum to stay away from the dampers.... build up reasons. ??
Try a cap that has a top plate area and smaller pipe to the top of cap housing...
But im not sure you going to know if its ok without measuring the draft or testing over a long period of time... The new cap might help at full burn but also cause smoke issues at reload or lighting, wind, cold weather...its really a trial and error...and more difficult without a constant draft gauge.
A damper just above the outlet is another option and just watch the flue temps. So if your draft is .14 and you want to get to .10 and under I dont see a cap reducing the draft enough so key damper is probably best.
But im not sure you going to know if its ok without measuring the draft or testing over a long period of time... The new cap might help at full burn but also cause smoke issues at reload or lighting, wind, cold weather...its really a trial and error...and more difficult without a constant draft gauge.
A damper just above the outlet is another option and just watch the flue temps. So if your draft is .14 and you want to get to .10 and under I dont see a cap reducing the draft enough so key damper is probably best.
Buildup is caused by the flue gases getting below condensing temp. If they exit the chimney top at >250ºF buildup should be minimal. The first step to prevent buildup is burning only fully seasoned firewood. Second step is to keep the flue gases hotter during the outgassing stage with double-wall stove pipe connected to an insulated chimney or chimney liner.
cabinwarmer
Feeling the Heat
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