Supercharging the Englander 30...Project OverKill.

[BurnIt13]

So I must have taken some crazy pills this morning. All I can think about is turning my already very efficient Englander 30 into an even more efficient wood eating machine. I've been day dreaming all day about hot rodding it. I guess I must be spending too much time on this site!

Lets face it....the NC30 is a budget stove. Englander has great customer service and produces a great stove for the money but there are some improvements that can be made. The goal is to make a more controllable stove with a better insulated firebox. Here is what I am asking from Santa this year:

Air Control Improvement

• There have been a number of threads lately on where the air comes from in the Englander 30, why it should be modified, and how to do it. Thread 1, Thread 2,
• Generally speaking....reducing or blocking the doghouse air gives the primary air lever greater control over the fire. This allows YOU to actually control the fire.
• Reducing the secondary air inlet some how improves the secondaries. I can't quite figure this one out...someone please tell me how!

Ceramic Baffle Board Improvement

• The NC30 comes with two ceramic boards that sit side by side N/S on top of the secondary tubes. The problem is that they are cut undersized. Users report of a 1/4-3/4" gap between the boards. This lets alot of heat and fire go right up the flue which makes for a cooler firebox. Many people just get some door gasket and slide a metal rod inside of it. This is exactly what I've done...and it helps. But I want more.
• I want more insulation. My parents Quadrafire 4300/3100's (I might have the #'s messed up) have a 3/4" ceramic baffle board and 1" of ceramic fiber insulation. Their secondaries light up almost instantly. A few people on here have replaced their ceramic board with two criss-crossing layers on their NC30's to eliminate gaps. It seems like it helps a lot. Like this thread...
• Skyline Components (and others) sell raw stock for ceramic fiber board. This is the company commonly selling it on eBay. You'd want two 1/2"x24"x36" B12T12C boards. $27.36 a board. Click Here...

Insulated Fire Brick

• Now we're going to get a little more crazy... Part of the reason I believe my parents Quadrafire stoves run excellent is because of the well insulated firebox. I believe these stoves use insulated firebrick. Hotter fires run more efficiently...right? Augie recently created a thread on Hot Rodding his Avalon Stove
• There happens to be a pottery store just an hour from me here in MA that sells insulated firebricks. $4.69 per firebrick. They need to be cut in half though....but at least I'll only need half as many. Sheffield Pottery Here is another source... Bailey Pottery Supply in NY

Now Really Crazy....Ceramic Coatings

• Here is where it gets really silly. In the refractory furnace land....a coating exists called ITC-100. Its expensive but really improves performance in refractory furnaces. It significantly reduces fuel needs to produce the same temperature fire.
• Insulated Fire Brick (IFB) is very soft compared to normal stove brick. It can be damaged easily. ITC-100 hardens and strengthens the outer coating of the brick....giving it a much longer service life. It also does a very good job at reflecting radiant heat......which goes back to the hotter firebox with less fuel idea.
• The problem is that its expensive. $65 for a pint shipped. That is about enough to cover all of the firebrick and the ceramic baffle boards in the firebox. Best price is at Budget Casting Supply. Click the link for pricing and technical data. Also available at Baileys, link above.

The point?!?!? Better air control and a better insulated firebox will allow you to have the same temperature fire but with less air. Less air means longer burn times.

What do you think? Should I give it a shot? Oh wait...it will cost about $180 shipped to do all this. Yup...definitely day dreaming. But If Santa is out there reading this and wants to deliver the materials for the project I promise to post scientific results on Hearth.com!

 

[dorkweed]

If you're heating your home with the Englander 30NC in your signature now, I'd probably wait until the warmer months to do this Definitely sounds interesting and possible though. It'll most likely void the warranty on your stove though!!

 

[BurnIt13]

If you're heating your home with the Englander 30NC in your signature now, I'd probably wait until the warmer months to do this Definitely sounds interesting and possible though. It'll most likely void the warranty on your stove though!!

It sounded like an excellent idea until I found out how much it would cost! At best, I'll maybe replace the ceramic boards the next time I take them out to clean the flue (late-mid January maybe?). Mine are two years old, fit poorly and are a little beat up from some whoopsies.

But it would be nice to do it all at once to see how big a difference it would make.

 

[Todd]

The thing that scares me about these mods is how will it effect the steel? Is the steel strong or thick enough to take those higher internal temps?

 

[BurnIt13]

The thing that scares me about these mods is how will it effect the steel? Is the steel strong or thick enough to take those higher internal temps?

Good question....but I'm not trying to make a forge or smelt some gold or anything. I would think the steel would be the same temp. The big difference is that because the firebox is more insulated, I can have the same temp fire while turning the air down further.

Lets think of two extremes.

1. Lets say one extreme is that my ceramic baffle board is shot and has a 1" gap in the middle. Most of my heat is exiting the firebox immediately and going right up the flue. My secondaries would be very poor if I even had them at all. I'd have to keep the primary air open more to have a good fire. And it would not be a clean efficient fire because the secondaries wouldn't be doing much. All the heat and particulates would be escaping right up the flue. The wood would be consumed quick.
2. Now lets look at the other extreme, this particular thread. The firebox is well insulated and the secondaries are going to light off earlier. The heat will stay in the firebox longer before escaping up the flue allowing a very slow burn but with active secondaries. It will be a clean and efficient burn but with a lot less primary air. It should provide a very long burn.

At least thats how I'm thinking of it......maybe someone with more knowledge than me can set me straight. What I think I'd like to build is an Englander 30 if Englander 30's were built for highest possible performance instead of compromised for lowest price.

 

[granpajohn]

The insulated firebrick....
....seems like a quick, easy, and not all that expensive thing for a stovemaker to do. If it made much difference, I would think they'd have tried it.
(Speaking as a QF owner)
I'll be curious to see the results if you do it.

 

[dorkweed]

By insulating the firebox better so that you get a better burn/secondaries etc..........................would the insulation not also keep the heat away from the metal box (aka, the stove) and more heat go up the chimney????

I mean that there is a "break even" point somewhere. Where it is, I don't know. Theoretically, you can insulate the firebox enough that almost no heat would transfer to your room/house. We want heat transfer but with efficiency Where is that fine line?????? I dunno??

 

[granpajohn]

After I posted on this thread, I read another very recent thread on IFB....
https://www.hearth.com/talk/threads/hot-rodding-the-stove-started-today.100333/
...for those who missed it. (Like me. I feel a little foolish, but oh well.)
(Edit to make it page 1 not 2)

 

[BurnIt13]

By insulating the firebox better so that you get a better burn/secondaries etc..........................would the insulation not also keep the heat away from the metal box (aka, the stove) and more heat go up the chimney????

I mean that there is a "break even" point somewhere. Where it is, I don't know. Theoretically, you can insulate the firebox enough that almost no heat would transfer to your room/house. We want heat transfer but with efficiency Where is that fine line?????? I dunno??

I agree 100% with this statement. However, there is 5" or so of space between the fire brick and the ceramic board above the secondary tubes. This is the side of the stove. Most stoves don't radiate most of their heat out of the sides though....they radiate it through the front glass and from the top. All of that heat isn't going to magically stay in the stove somewhere...it has to leave eventually. The hot gasses are still going to pass across the top of the stove and out the flue.

But your guess is as good as mine.....

 

[lowroadacres]

This reminds me of hyper-milers. If you go for it I can't wait to see the results.

 

[BurnIt13]

This reminds me of hyper-milers. If you go for it I can't wait to see the results.

Funny you say that. I spend a lot of time lurking cleanmpg.com and gassavers.org. Of course I have a Toyota Tacoma not a Prius...the best I can do is 23mpg. But I digress.

To address some concerns above...Augie started a thread recently (listed above) about Hot Rodding His Stove. He replaced his normal brick with firebrick and it seems like it made a significant improvement.

Huntindog1 has also done this but he coated his with ITC-100 as well. AND he put some ceramic insulation behind the firebrick. He also talks about a significant improvement in secondary light-off.

Here is a thread resurected this past October about the pros/cons of different types of bricks. Some even replace their firebricks with SoapStone! Firebrick thread

After X-mas finishes up I just may have to try some of this.

 

[granpajohn]

This reminds me of hyper-milers. If you go for it I can't wait to see the results.

First thought...It's easy to quantify results with MPG. Would want actual temp/Btu numbers for a stove, but don't know how to easily get that.
I added a tiny bit of insulation to my setup, and yes it "feels warmer", but I can't quantify with data.

But, keep at it. "Feels warmer" is still good reading and usually worth a try at least.

 

[jharkin]

"Project OverKill." .... Did you send Scotty his royalty check?

 

[BurnIt13]

The crazy pills must still be working....I have another idea. What if I made the air temperature for the secondaries a couple hundred degrees hotter?

First a short story:
The inlet for the secondary air is at the back of the firebox right above the OAK hookup. The flexible SS hose that connects to the OAK gets COLD! With my IR gun I am noticing the air back behind the stove is the 50's at times. The 50 degree air then enters the secondary inlet and gets warmed by the back of the stove on its way to the secondary tubes.

Crazy talk now.....what if I welded a 1.25" steel hose nipple to the secondary intake port. It would take a little fabrication but thats okay. I could then attach a stainless high temp (800F+) flexible duct hose and route it to the side of the stove just below the side heat shield. I would then secure a 12" piece of 1.25" aluminum tubing in between the side heat shield and the stove. Then I would connect the flexible duct to the aluminum tubing. The air for the secondaries would now be drawn from the space between the stove and the heat shield.

The temperature in between the heat shield and the stove runs about 500F on a hot fire half way up. Even with a significant loss in temperature the air entering the secondary port would be a few hundred degrees hotter than before.

On a fresh, cold stove it wouldn't make a difference right away....but once the stove is warming up.....Hello secondaries!

Is there a 12 step program for hearth.com addicts available?

 

[pen]

Reducing the secondary air inlet some how improves the secondaries. I can't quite figure this one out...someone please tell me how!

Draft is the engine of the stove. If a certain chimney has mediocre to low draft, then the operator would certainly want both the dog house and the secondary air inlet to be as wide open as possible to get the best burn in this situation. I have a fair to good draft, and wouldn't consider altering either for my 30 as they don't cause me any issues and I like that dog house air, especially when I'm trying to burn down a coal bed.

If someone has an excessive amount of draft (such as a very tall chimney on a straight run in a cold climate) then restricting the dog house air and/or blocking a bit of the secondaries can keep the stove from over firing, making the secondaries / burn more controllable, not better.

pen

 

[Augie]

Your biggest benefits will come from the insulating fire brick. I would start there, by just doing the IFB first nothing is irreversible. The refractory coating, the ITC 100, is cheaper than that. You only need about a quarter of what you think. There are a few places selling it for $20.00 with shipping.

As for insulating the firebox more and decreasing the heat output, we'll you can rest assured that that will never happen. The radiating surfaces are designed to be the roof 'AFTER' the secondaries and the front. Insulating the top of the fire box keeps the secondaries hotter. The exhaust gasses still have to travel along the top of the stove. The only thing between the exhaust gasses and the room is a piece of sheet steel, which you are not going to coat.

 

[BurnIt13]

Your biggest benefits will come from the insulating fire brick. I would start there, by just doing the IFB first nothing is irreversible. The refractory coating, the ITC 100, is cheaper than that. You only need about a quarter of what you think. There are a few places selling it for $20.00 with shipping.

Dear Sir....thank you. And is it possible for you to point me in the right direction or PM me your source if you could? The best I could find was $65 shipped and I thought that was a bargain! Every one else seems to want $90-100 for a pint before shipping.

Did you coat your ceramic baffle board with the ITC-100? It says it is appropriate for that.... Might make a significant difference...maybe.

 

[mrmojo182]

Please share the info if you find the ITC coating or an alternative coating. I just ordered the additional boards for the top of the stove, and I'm pretty close to purchasing the ifb.

Jon

 

[BurnIt13]

Please share the info if you find the ITC coating or an alternative coating. I just ordered the additional boards for the top of the stove, and I'm pretty close to purchasing the ifb.

Jon

Jon....the best price I can find for the ITC-100 is $65 and the link is at the bottom of the first post. Augie stated that he has a better price so we'll have to wait for him on that one.

As for the IFB's... be sure to measure not only how thick your existing brick is....but how thick of a brick that will fit. If you need to cut the bricks to the correct width it might not be a bad idea to cut them a 1/4" too thin. That way you can put some ceramic insulation behind the bricks.

What type of stove to you have? And please raise your right hand and promise you will share the results on this thread once you do the modifications!

 

[Huntindog1]

(broken link removed to http://www.hightemptools.com/itcproducts.html)

 

[Huntindog1]

As we all know the small stoves have better efficiencies as they are easier to heat up and the smaller space of the fire box its self is small and easier to keep temps up and secondaries firing. I too believe heat is an important factor in the efficiencies of these stoves , keeping the fire box a little hotter will improve the operation of the stove. I say all of this as making these improvements to a large stove such as a NC-30 should make a nice difference in stove operation since the stove doesnt have the extra insulating blanket on top of the baffle boards. The stove being a large stove has alot of a room in the fire box to heat especially as the wood burns down and this creates more and more space in the stove making it harder and harder for the secondaries to keep firing and burning the wood gases. Everyone knows how a full stove with just a little space at the top is easier to get some really nice secondaries going. Everyone also knows how if you just throw one piece of wood on a bed of coals the secondaries dont get going very good unless the stove is super hot already. Space in the stove is part of the equation when thinking about keeping the heat up during the entire burn cycle. You have to remember when the stove is in a over night low input air setting mode that as the big open spaces in the stove increases as the wood burns down this makes it harder to keep the secondaries firing and lowering emissions but at the same time there is not as much wood gases left but in a large stove there can be many pieces of wood not completely burned yet as for example the stove is half full and having half the fire box open need to keep the heat up for secondary burn. So this all means a large stove can greatly benefit from these type additions.

I dont think keeping more heat in the fire box will hurt the the stoves as we operate these stoves at the lower end for long burns and at the wide open end.

 

[BurnIt13]

(broken link removed to http://www.hightemptools.com/itcproducts.html)

Ah..I see, that pricing is for less than a pint. For a pint its a little more after shipping.

The is roughly 3.5 sq.ft. of brick surface area in the stove and about 3 square feet of surface area on the ceramic baffle.

The info on the High Temp Tools website says a half pint will cover up to 6 sq.ft. and a quarter pint 3. Makes me think I'd need 3/4 pints worth just in case of over application. Same price is a full pint.

How much did you use? And did you apply it to your ceramic baffle board?

 

[Huntindog1]

I used a half pint but I also coated my bottom side of the baffle boards. You only need a thin coating they say.

My stove is smaller 2.12 cuft

 

[BurnIt13]

I used a half pint but I also coated my bottom side of the baffle boards. You only need a thin coating they say.

My stove is smaller 2.12 cuft

Since you did exactly what I'd like to do, albeit in a smaller firebox, how much of a difference did it make? Night and day? How does your stove top temp compare to before when using a similar load of wood? Do the modifications enable you to reduce the primary air more?

Thank you, oh wise one.

 

[Huntindog1]

The reason the turning down the secondary air can help your secondary flames is that , if your draft from the flue is strong then too much air can be pulled into the fire box and this also means the air is pulled in at a more rapid rate. Less time for the air to be heated up from the more rapid air flow from the strong draft from the flue. The more air thats slightly cooler maybe cooling your temps up in the top of the fire box so thus you might have less secondary action. Remember your temps up there in the top of the fire box needs to be like 1000F and compare that with the temp coming in from the secondaries and you can see why the secondary can cool the temps in the top of the stove down from the needed level of 1000F.

Now if you can fine tune the system with a valve you can slow down the air flow thru the secondaries. This gives more exposure time for the air traveling those passage ways to heat up. Now the air entering thru the secondary tubes is hotter and having less of an effect on the temps in the top of the stove that are needed for secondary flaming. Plus slowing down the air flow thru the stove much like when we close down the primary air as there is less air flow thru the stove the fire box heats up hotter due to less air flow thru the stove. You see in alot of stoves they try and create addition routing of the air to make for more residual time to heat up, concept is the same here in this example just lowering the air flow and less cooling of the fire box , more heat for secondary burn. As I think the hotter the fire box the less air it takes to burn smoke. Plus I think the hotter the fire box the more efficient it burns the smoke.

Lastly you can use better quality of wood thats been seasoned longer , like 3 years and see improvements also. So if you dont like messing with the stove try improving your wood pile.