Looking for the best Coal stoker for my applicatiton.

Good choice. I'm sure you will be very happy with the performance of the new boiler. How did you like those PA hills and turns on the road to Jeff's?

I was thinking.... "These are some awesome roads to take a bike ride on with my wife on a Sunday afternoon" They were fun in the little "pocket rocket" I took to Jeff's.

Hello MXer congrats on your purchase I see your a bike rider i do not know if you seen the post on here about the bike / yuengling tour / coal breakers tour if you are interested go to the post and read it you would have lots of twisty and curvers black top roads to and from the breakers and some dirt roads but that would not be a problem there will be a few trucks there you could just put it in the back untill we get back on the black top just a thought well hope to see ya take care and good luck with your new A.H.S

According to Jeff at AHS, it is important to have a good drafting chimney during the "off" condition of the boiler. That being said, I am looking at how best to achieve that good drafting chimney on the outside of my house. I have found some stainless chimney makers, but none offered 316 stainless. I have a couple of questions:
1) What MFG's offer the best Stainless Insulated Chimney?
2) What is the right way to build an Insulated Clay lined block chimney?

Mxer,

You're looking to make a Class A chimney. As Yanche has pointed out in the past, few if any manufacturers consider coal burners in their lit. Coal smoke doesn't have the problems of wood, so chimney properties are more like oil-burners. But, coal forms corrosive deposits; you want good stainless, or better, masonry.

There is "class A" stainless chimney pipe with all the fittings for new. Here's a primer on these: http://www.woodstove.com/pages/prefab_chimney.html

There are single wall 316 flex *liner* that allow you to use old leaky masonry. Here's a good, expensive brand - there are many (cheaper) others: http://www.protechinfo.com/ventinox.html

Masonry (8x8) is the best solution and probably only a couple hundred more to build or buy.

Are you going to do the work yourself?

If you want to build an insulated block chimney, you could use the larger chimney block, the ones meant for an 8-9" clay liner, and use a 6" liner and pour insulation around the liner, filling the gap to the block as you build the chimney.

However I think that is overkill. How tall will the chimney be?? Are you located on a hill or in a valley? Which side of the house would the chimney be relative to the prevailing wind??

If you are going to burn coal all year, providing domestic hot water, you will need a tall chimney. The temperature differential to ambient temperature during summer will minimal. A tall chimney with a prevailing wind pulling a draft out of the flue will be needed.

Or you could build a standard block chimney with clay liner and insulate the outside of the chimney. Enclose it in framing and insulate it with foam-board, cover it with siding.

A tall chimney with a good prevailing wind without buildings or rooflines blocking the wind will provide a good draft.

Personally I wouldn't spend the $$ on a SS chimney, spend the $$ on a block/clay chimney, get some help if needed or do it yourself. Rent scafolding and take your time. It's not difficult. I built my block chimney standing in the bucket of my front loader.

Greg L.

In my opinion an insulated chimney for an AHS "coal gun" boiler is a complete waste of money. The only time you need natural draft is when the combustion blower is off. During that time there is little if any heat going into the vertical part of the chimney. What are you going to insulate? There is no heat to insulate. To vent the small amount of idle combustion gases all is needed is a tall pipe. Consider building something cheap at first, just uninsulated 10 ft sections of galvanized duct pipe. No need for a barometric damper if it's two stories or less.

The stoker/boiler will be located in the basement, so say 4-5' to reach the first floor plus 8' for the 1st floor and 10-12' for the attic and roof and then add 3' above roof will give about a 25-28' Chimney. AHS recommends a 5" Chimney. I have a steel roof and the Chimney will be located at the back of the house close to a hill. How do my numbers look?

Your thimble to connect to the vertical portion of the vent (chimney column) should be as high as possible. Why? Because you want a tall vertical 5" diameter pipe directly connected to the boiler. The flue gases will have ash in it. Ideally you do not want to convey this ash along with the gases. You want it to drop to the boilers ash pit. The AHS "coalgun's" ash pit outlet is directly in a vertical line with the flue outlet connector. By having a tall vertical pipe there any ash will have to be carried up by the flue gases. Something difficult. The ash ideally will fall to the ash pit. Now in practice it does quite work that way. The ash outlet is cone funnel at the bottom just above the ash pit. It gets clogged and requires periodic poking. I remove my flue connection at the top of the boiler and poke at it with a old CB antenna. Not an ideal clean out mechanism but doable. Be sure the power is shut off. You don't want the combustion blower turning on! It's needed monthly in the heating season. In the infamous Bureau of Mines report on the A-A boiler they say ...

"An imperfect feature of the Anthratube is that the fly-ash collector does not deposit all of its catch in the refuse. A small part reaches the floor near the ashcan within the base. The fly ash accumulates, and in time some of it will be dragged out onto the basement floor when the can is removed. It is then desirable to clean out the base. If this fly ash ceases to fall, it is evidence that the spill hole at the bottom of the collector is plugged. This occurred once, but it was readily opened by opening the door at the left of the base, reaching up over the grate, and dislodging the accumulation with a short rod."

This design deficiency has be carried over to the Esland/AHS design. I've not tried to clean it from the bottom as described above.

Be sure the horizontal run of flue pipe has adequate clearance from any combustionable surfaces. Also tape any joints. The combustion blower will blow ash through any untaped joints.

Yanche is right on the pipe. Be sure any horizontal runs pitch up at 1/4" @ foot. I'll add a tip from I believe is from the Axeman install manual. "Insulate the pipe with asbestos" is the qoute, however you will need another product obviously. But it is important on the AHS and Axeman as they are pretty much self cleaning by design and the procedure inhances the process.

The best "Class A" pipe, in my opinion, is made by Security. It offers a 30 year warranty, even if you are burning coal. For the single wall 316TI liners I too like the Ventinox (made by Protech Industries), but read the warranty. It is a lifetime warranty except if you burn coal. Then the warranty drops down to 10 years. Homesaver brand 316TI Ultra-Pro is an outstanding liner as well, and is a lifetime warranty, even if you are burning coal.

Mike

Charlie Z wrote:Oliver, how old is that SS pipe and was it 316?


(The local oliver dealer was a friend of my dad's in town and, very young, I remember gawking at them while they talked. One of those very pleasant bit memories. We were always 'oliver people'. There were lots of Oliver and F-A and only some green around here, then.)

Not sure if it's 304 or 316. I was looking to buy metal chimney with 316 (or better)stainless. Went to Amish man who sells metal chimneys. His neighbor sells the coal stoves. He didn't know what grade stainless pipe he sold. We looked on boxes , literature , on the pipe itself , etc.. Couldn't find any info. Amish man claims lots of people buy that pipe from him , and no problems. So , I took my chances. I haven't had any problems with the chimney , other than some very minor surface rust from the top - down about 12 inches. The cheap chimney cap corroded apart , allowing water to enter the chimney. The chimney was 6 years old when I noticed the cap was shot. That's when I noticed the surface rust near the top of chimney. The chimney has many good years left in it , as long as I maintain it. Would I put another metal chimney in??? Most likely. Only due to ease of installation. Next time I'll verify the quality of stainless. I would still recommend masonary chimney over metal.

Yanche wrote:In my opinion an insulated chimney for an AHS "coal gun" boiler is a complete waste of money. The only time you need natural draft is when the combustion blower is off. During that time there is little if any heat going into the vertical part of the chimney. What are you going to insulate? There is no heat to insulate. To vent the small amount of idle combustion gases all is needed is a tall pipe. Consider building something cheap at first, just uninsulated 10 ft sections of galvanized duct pipe. No need for a barometric damper if it's two stories or less.

Hi Yanche,

I will have an S-130, my chimney will be 3 stories tall - two story home with stove in the basement, will I need a barometric damper? What's its purpose?

The chimney will be facing west and we will be on top of a ridge. There are some trees blocking the view of the valley... but blockage is minimal. I think we'll have a fairly constant breeze on top.

All thoughts would be much appreciated.

You should use a baro with anthracite, especially with a 30' chimney. Its purpose is to break the draft through the appliance at a preset point, Usually around .05-6 on a stoker. It allows room air to take the place of the draft through the unit preventing an overdraft from reving up the fire and or pulling heat out of it.

http://www.fieldcontrols.com/draftcontrol.php

http://www.fieldcontrols.com/draftcontrol.php#draftwork

My previous post on insulation was for the stovepipe itself, not the chimney.

Thanks coaledsweat. The links are helpful - I guess I'll need an RC type. Can I pick these up at the local hardware store? Pret.