newcomer firing a 1945 Defiant

[dentman4411]

Hey all thought id stop in and say hi. Just hooked up my defiant 1945 vermont castings stove. thing is HUGE! I have a bazillion questions but will share what ive done thus far:

bought used off CL and refitted the following gaskets; doors and windows, griddle, ash pan door, and rear plate that sits in front of refractory but behind fire brick. also new fire brick.

had a local stove guy hook up my chimney, he used single wall black inside up to a triple wall connector and then 3 sections of 8" triple wall. Its just barely 15' of chimney, i think the least amount recommended for the stove.

I have a rear heat shield but plenty of space so i situated it 23" to the corners of a non protected combustable corner wall. That part is to spec right from the owners manual. Finally the stove is sitting on thick versailles slate tile mounted to 1/4" hardibacker screwed to 5/8" plywood flooring sitting on 2x10 joists. temps under the stove have reached 160 degrees coming from a rutland temperature gauge.
Stove temps at the time were 550-560 degrees.

my 2 questions and ones that are concernning me the most

1. In cat mode, with air control valve closed, stove still fires and runs 500 degrees. Is the stove capable of shutting down, or is it kind of like once its fired you have to strap in and hold on...

2. Chimney guy that installed it feels the hardibacker/slate tile the stove sits on is adequate heat protection for the wood beneath it but Im not satisfied this is true. Should I use a bottom heat shield and woluld even that be enough or do i need a UL listed hearth pad. I was hopeful to let the stove sit on the tile without any additional needs both for asthetics and further reducing the overall chimney height.

thanks in advance Im sure ill meet some nice folks here

 

[KaptJaq]

2. Chimney guy that installed it feels the hardibacker/slate tile the stove sits on is adequate heat protection for the wood beneath it but Im not satisfied this is true. Should I use a bottom heat shield and woluld even that be enough or do i need a UL listed hearth pad. I was hopeful to let the stove sit on the tile without any additional needs both for asthetics and further reducing the overall chimney height.

Welcome to the forum,

From the defiant manual:


A tremendous amount of heat radiates from the bottom
plate of your stove. The floor area directly under and
around the stove will require protection from radiant
heat as well as from stray sparks or embers that may
escape the firebox.
Heat protection is provided through the use of a Ver-
mont Castings Bottom Heat Shield #1905. Spark and
ember protection must be provided by a floor protector
constructed with noncombustible material as specified.
Most installations will require the bottom heat shield be
attached. Only when the stove is placed on a complete-
ly noncombustible surface such as unpainted concrete
over earth may it be used without the heat shield.
Even when the bottom heat shield is installed, you must
provide special protection to the floor beneath. For
installations with the heat shield attached, use a non-
combustible floor protector such as 1/4" nonasbestos
mineral board or equivalent, or 24 gauge sheet metal.
The floor protector may be covered with a noncombus-
tible decorative material if desired.

http://www.manualslib.com/manual/186203/Vermont-Casting-1945.html?page=10#manual


Do you have the bottom heat shield?

KaptJaq

 

[dentman4411]

Hi KaptJaq, no I do not have the bottom shield yet. I have read that paragraph in the owners manual several times. Its contradictory in nature, Im guessing they keep it vague to aviod legal issues. On the one hand it says "in most applications", then it says you NEED a bottom heat shield and then it says even if you have a shield you need even more attention. I do have 1/4 inch non asbestos board, hardibacker. But in testing on my workbench it provides zero thermal protection. everything you put in front of the hardibacker passes right through it.

Wood has a generally accepted flashpoint of about 572 degrees but there is discussion that suggests numerous exposures to hot, but lower temps can lower the flashpoint of the wood.

 

[KaptJaq]

The way I read it, if you are on anything but unpainted concrete over earth you need the bottom heat shield. With the bottom heat shield you need spark and ember protection. Any other installation would be contrary to the installation instructions. They do not give a minimal thermal resistance for the hearth pad without the heat shield. Without the heat shield your current installation is not to specification.

Repeated exposure to the heat through the hardibacker will lower the combustion point of the wood below the hardibacker. It might not be dangerous today but eventually it will be. I would not be comfortable with the current install in my home.

KaptJaq

 

[begreen]

The manual's directions are pretty clear. In most cases you really need a bottom heat shield for the stove. In addition you need to have a hearth that shields against hot embers.

Cement board will work for the latter task as will a sheet of metal or the slate hearth. But it's purpose is strictly ember protection. It is not the same as the bottom heat shield that attaches to the stove. You need this part. If unable to find at a VC dealer, then maybe one could be fabricated.

(broken link removed to https://www.lehmans.com/p-3601-bottom-heatshield-for-vermont-castings-defiant-wood-heat-stove.aspx)

 

[dentman4411]

Kapt and begreen thank you - the two comments made it all make sense in my mind. i guess I was confusing the task of one for another. Ordered the bottom shield from lehmans. thanks.

can either of you comment on the stoves ability or lack thereof to "shut down" I can get a nice bed of embers, add logs, and stove will burn for hours with the air inlet closed. Ive replaced all gaskets. thanks again

 

[BrowningBAR]

can either of you comment on the stoves ability or lack thereof to "shut down" I can get a nice bed of embers, add logs, and stove will burn for hours with the air inlet closed. Ive replaced all gaskets. thanks again

It is how the stove tends to operate. Sometimes you can lock it in at a lower temperature, other times the temps like to climb even when the air is shut down.

 

[dentman4411]

ok i got the bottom shield, along with the side cars and the ash pan shield. the floor beneath is significantly cooler now. Still though, it is warm to the touch after a long fire, say 6-7 hours where the stove runs about 575 degrees. its not "hot" as i can leave my hand underneath indefinitely but is this anything to concern with? thanks again folks.

j