Dislodged Parts on my 1975 Vermont Castings Defiant

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

IDroppedMyStove

New Member
Oct 28, 2021
4
New Hampshire
Hello,

I am in the process of refurbishing a 1975 Vermont Casting Defiant that was given to me by a friend.

I had finished wire brushing the exterior of the stove and was moving is with my tractor bucket outside to be painted.

Long story short, I tilted the bucket forward when I meant to tilt it back and the Defiant fell off the bucket. It was from a height no greater than 18 inches onto a crushed stone driveway, and as far as I can tell the Wood Stove is undamaged.

However, the impact dislodged a few parts from the inside of the woodstove (see photos included). The plate with a curvature at the top and a floral pattern (which I've only been able to identify as an "access plate") is housed on a rail in the back of the inside of the stove, above the 1975 stamp.

I'm not sure where the other part goes (pardon the rust damage) but any help/tips would be greatly appreciated for putting this all back together.

I'm hoping to be able to reinstall the dislodged parts. I've attempted to disassemble the flue damper rod (which sits at the top of the rail I'm hoping to get to) by removing the exterior handle clamped on the flue damper rod, but the it doesn't seem to be removable.

Any suggestions as to how to put this old girl back together? Thank you in advance for your help!

20211028_074857.jpg 20211028_074848.jpg 20211028_074840.jpg 20211028_074829.jpg
 

fbelec

Minister of Fire
Nov 23, 2005
3,320
Massachusetts
they should just slide back together. you can get at the first picture easily if you have a top vented stove
 

peakbagger

Minister of Fire
Jul 11, 2008
7,312
Northern NH
IMHO, time to take it all apart as odds are you loosened up other seams. Good time to clean up an rebuild the secondary air channel at the same time. 8 Hours with wire cup brush on an angle grinder will do wonders. Add in some high temp stove paint and it will be good for another 20 years.
 
  • Like
Reactions: fbelec

begreen

Mooderator
Staff member
Nov 18, 2005
93,801
South Puget Sound, WA
Also, clean up the bypass mechanism of any rust. It should work smoothly and freely.

Here is a diagram showing the parts. I am guessing that this is a Defiant II. The larger plate sits in the lower fireback plate and am guessing that the narrower rusty part is the bypass baffle, but I have never taken one apart. @Defiant do you know?
 

IDroppedMyStove

New Member
Oct 28, 2021
4
New Hampshire
Also, clean up the bypass mechanism of any rust. It should work smoothly and freely.

Here is a diagram showing the parts. I am guessing that this is a Defiant II. The larger plate sits in the lower fireback plate and am guessing that the narrower rusty part is the bypass baffle, but I have never taken one apart. @Defiant do you know?
Any chance you could retry sharing the parts diagram? The hyperlink you may or may not have included doesn't seem to be available. Also, @Defiant, any chance you could chip in? Thank you for your reply!
 

IDroppedMyStove

New Member
Oct 28, 2021
4
New Hampshire
they should just slide back together. you can get at the first picture easily if you have a top vented stove
The bottom slides into the grooves, but the top does not fit behind the rail as it is too wide. What do you mean by "get at the first picture easily"? Thank you for your reply!
 

peakbagger

Minister of Fire
Jul 11, 2008
7,312
Northern NH
The original design of the stove was very efficient compared to other stoves. The stove is started with the bypass open, smoke and heat went right up the outlet of the stove. The high efficiency part was when the bypass is closed, the smoke from the fire is pulled into a secondary chamber located on the right side of the stove. Fresh heated secondary combustion air was directed into the chamber causing a large portion of the unburnt gases (mostly Carbon Monoxide AKA CO) to burn more fully. The fresh air comes from the primary air flap. There is also a small round port on the lower left hand side that could be opened to crudely "tune" the secondary air flow. How the secondary air gets from one side to the other is the secondary air channel. It is formed by a "C" shaped channel in the rear fireback and the rear casting of the stove. Refractory is smeared on the edges of the channels facing each other and then the rear fire back is slid in place against the rear stove casting. Once in place more refractory is smeared on the outside top of the two upper mating channels and then wire screen is smoothed into the wet refractory and formed into smooth surface. A wooden rod is used as tool to slide inside the channel to smooth things out on the inside of what is now a sealed tube that runs from the left to right side of the stove. As half the channel is on the back of the fireback, any air going through it is preheated which improves secondary combustion. Once the smoke burns in the secondary chamber is routed to the area behind the fireback before exiting the stove. If using dry seasoned wood, the combination of more complete combustion and a much longer flame path across the exterior surfaces of the stove means more heat and less wood.

The down side is that the rear chamber behind the fireback is difficult to access with the stove assembled. There is removable cast iron plate under the bypass damper that can be removed to use a ash vacuum to remove any fine ash that will fill that normally inaccessible area. If its allowed to build up in that area it causes the front of the fireback to be much hotter than the rear due to the ash acting as an insulator and no flow of flue gas. The front of the fireback now expands more on the front face than the rear and eventually the cast irons distorts and then cracks. Once that happens the fire seeks the path of least resistance through the crack and less goes through the bypass. Inevitably when the fireback distorts that secondary air tube which was so carefully formed leaks into the rear chamber and skips the secondary burn chamber. Unfortunately that air that leaks into the rear area is the wrong place and by the time it gets to the unburnt gases the temp is too low to burn the CO (which needs around 1800 F).

There is detailed set of illustrated instructions floating around the web that describes step by step how to convert a Defiant 1 to a Defiant 2 which shows the secondary air channel details. It really the only hard part to assembling the stove.
 
  • Like
Reactions: fbelec