Kiln Box for Nyle l53

[DWyatt]

I have seen a lot of bits and pieces spread around here of the different ideas that people have used to build their kiln chambers, but I keep losing track of the information. Here is my plan then i will follow it with a couple questions. 

I am going to build a lean to on the end of my barn that will be the kiln. It will have outside dimensions of 9' deep x 15' wide with a 12'-6" door. I want to start with a 4" concrete slab with 8" thickened edges and probably some sonotubes as a foundation. I plan to use 2" foam, 2' deep surrounding the slab and 2" foam under the slab. I will then frame up 2x6 walls on all 4 sides (even the side against my barn) and blow in fiberglass insulation to the walls. The inside will have 2 layers of polyisocyanurate foam board with the seams staggered. Then regular 1/2" CDX over that painted with just regular exterior paint. The ceiling will have blown in insulation as well and the outside will be sheeted with metal to match my building. The doors I plan to build out of 2x4s with blown in insulation and the polyiso insulation on the inside. This is where the questions begin.

I want to use face seals on the door but I am not sure if I should use aluminum angle bordering the inside with the seals on the face of the door and the angle or if I can do that with just lumber rather than the angle. On the bottom of the door, should I fasten a 2x2 to the slab and use the seal on that or should that be angle as well? Next question is the hinges. I am thinking of using 5" x 7" wide throw hinges to get the opening as open as possible. I plan to have a wheel on the end on each door to prevent the doors from sagging so I am thinking 3 or 4 hinges on each door should be plenty? The last part is the latches. I remember seeing somewhere where the link was given for a source of latches like on a semi trailer, but I cannot find it for the life of me.

Thanks is advance for the critiques.

[K-Guy]

Hi
Personally I would never use fiberglass insulation anywhere in a kiln. If anything use Roxul, it has moisture resistance if the kiln leaks. You chamber is large for a L53 and getting heated up at the beginning or doing a bug kill at the end is going to take a while. Regular paint will not seal the inside of the chamber, use aluminized roofing paint paint. It is the only thing that we at Nyle have found that will keep the seal during expansion and contraction from heating and cooling.

[DWyatt]

I guess I should have added, the majority of the heat will be coming from the OWB I believe which runs water at 180 degrees. Good point about the Roxul which I would assume is just rock wool insulation. As much as I despise that stuff, it would work better as you say.

[WDH]

Cam-Action Lockable Door Latch Kit w/ Narrow Hasp for Small Enclosed Trailers - Zinc-Plated Steel Polar Hardware Enclosed Trailer Parts 383200

You have to buy the 3/4" pipe separately.

[xlogger]

I guess I should have added, the majority of the heat will be coming from the OWB I believe which runs water at 180 degrees. Good point about the Roxul which I would assume is just rock wool insulation. As much as I despise that stuff, it would work better as you say.

I also use an OWB to heat my kiln. It does a great job except during the heat cycle when it gets below freezing. It would be good then except I got the stove before the kiln, if I would of plan ahead I would of got the next bigger one. It will work but you will have to add wood a few times a day (maybe over night) when cold if you are trying to heat home also. I just avoid heat treating on real cold nights here in NC.
Stan can tell you how to by pass your heater in your Nyle and just use your OWB.

[DWyatt]

@WDH that's what I was looking for. Thank You!

@xlogger My OWB is definitely oversized for my house. I keep my 1000 sq ft shop at 65° and the 1200 sq ft house at 70° in 0° weather and still only load wood twice a day. The OWB came from my parents where it was heating their ~2500 sq ft house and 650 sq ft shop being loaded once a day. Thank You for the heads up. What kind of an exchanger are you using inside the kiln? I thought about using this stuff   http://www.fintube.com/finbraze-tubing.html   and doing a loop behind the circulator fans but I am not completely sure. I would then have to have some kind of control for the pump at the OWB to turn the pump on and off when the l53 calls for heat.

I am just in the pricing mode and plan to cash flow this thing next year and plan to give Stan a call to figure out the details once I start ordering materials.

[xlogger]

Been awhile now I forgot but its not that big 12-15" and maybe 6" wide. Water goes thru heat exchanger all the time if I don't unplug plug at OWB. But fan behind it is controlled on Nyle controller. Great setup.

[DWyatt]

Been awhile now I forgot but its not that big 12-15" and maybe 6" wide. Water goes thru heat exchanger all the time if I don't unplug plug at OWB. But fan behind it is controlled on Nyle controller. Great setup.

Is the fan you use anything special to withstand the acidic kiln environment?

[YellowHammer]

For the floor door face seal, I would recommend using a piece of heavy lumber to back up the seal, as the floor will see a lot of traffic and hard knocks.  My floor seal face is a 2x4 screwed down to the concrete.   I can drive over it, drop aq piece of wood on it, etc and not damage the face.

The L53 controller throws a relay for the heat strips when it calls for heat, rated for 1KW, but not more, and but I wouldn't wire that directly to the pump circuit.  I would use the the L53 as a trigger circuit to fire a secondary main relay at the pump.  That way the pump circuit is isolated form the L53 and you won't have to worry about overloading the L53 circuit.  The L53 is easy to identify in the controller unit, and would be easy to wire to.

[WDH]

Except for the sterilization cycle, and if your chamber is well insulated, the L53 requires very little heat to operate if you have installed supplemental fans.  The motors for the compressor and fans give off more than enough heat to operate the unit without the heater except for start-up and for sterilization.  I routinely dump excess heat with my kiln, so I have too much heat rather than not enough for the normal drying operation.

[YellowHammer]

WDH is right on. 

So it's not like a conventional kiln where it needs constant supplemental heat.  It needs heat to get to 80F before the compressor will kick on, and it needs supplemental heat to go from the finished load temperature of 120F to the sterilization temperature of 150F.  

All other times in the cycle, heat will need to be dumped.

You could easily control that heat input with a PIL (Person in the Loop) controller.  I do it every run in the winter with my 2 KW heat lamps to save time getting up to sterilization temps.


 

[WDH]

I use the halogen heat lamps too to get the heat that I need for start-up and then for the last step of sterilization.  I would say keep it simple.  You really do not need a OWB for heat for the L53.  Simply plugging in two halogen heat lamps might be a bit simpler.

[K-Guy]

@DWyatt
If you want to call me at Nyle, I'll be glad to help you.
Stan

ps @YellowHammer  and @WDH are nice guys and very helpful but not as good looking. 

[doc henderson]

that is not saying much, ehh.   .  to quote Dr. Sheldon Cooper, "bazinga!!!"   @K-Guy   @YellowHammer   @WDH  

[K-Guy]

@doc henderson 

[xlogger]

Been awhile now I forgot but its not that big 12-15" and maybe 6" wide. Water goes thru heat exchanger all the time if I don't unplug plug at OWB. But fan behind it is controlled on Nyle controller. Great setup.

Is the fan you use anything special to withstand the acidic kiln environment?

Not sure, I got the heat exchanger from a CB dealer that has now gone out of business.