US Stove Hot Blast Furnace Problems

Thank You!!!

I still have some things to do. I'd like to hook up the return air plenum, instead of sucking cold air and dust out of the basement. At the very least filter the air for the distibution blower. What's kind of nice is the chimnet effect, there seem to be warm air coming from most of the registers all the time. Might not get that with the return air hooked up, but then again how do you know until you try it.

Yesterday when I got home at five the house was 70 and I had a nice fire going and it looked as full as it did when I left in the morning. I didn't touch anything until about 8:00. Kicked on the thermostat, let it run, combustion blower on low. Let it burn for 10 or so then added 1/2 a bucket of stove, let it catch, shook the ashes until I could see the glow. I'm a little leary of poking the fire but I did just a little and the bed settled out a bit. Let it burn for another 10 or so and then topped it of. Temperature in the house came up to 76 or so. tuned down the stat to 70 and went to bed. 72 when I got up, don't believe the combustion blower came on at all.

I have a damper in the stack and have been keeping that closed except when loading. Stack temp has been right around 200 most all of the time except when first firing up the it's 350 or so. I don't have a manometr hooked up but it's on the list. I have a masonary chimney >20' but my hot water heater is still ducted to the same pipe as the stove. I want to change that shortly. I know that is robbing my a lot of my draft. Too many projects and never enough time.

Will report more results later.

tim

My fire didn’t work hard today either. I only put 12 lbs on this morning (about half a bucket of nut). Then 8 lbs on around 4pm. I’ll put a full bucket on tonight, maybe 20-22 lbs. My house was 73 most of the day, 71 now.

That sounds like you are running a good efficient fire. I bet your draft fully closed is running right where it needs to be. As your fire gets hotter, your draft pulls more.

I am at the exact same stage you are. I need to run cold air into my burner, and my gas water heater is just T’ed into my masonry chimney along with the coal burner. My setup wouldn’t take the cold air quite like yours would, but anything would help.

I honestly think my chimney is perfect for me. I was running around 300-350 degree stack temp and had my damper shut all the way. I caped the natural gas pipe for a few minutes to see what happened and my draft was too much. It shot up from -0.05 to -0.07. The damper was closed as much as it closes. Once you get a meter you could see exactly what it does for you. My chimney has got to be over 20 feet too, half exposed & half inside. I don’t think I’m going to leave it the way it is. When I upgrade to a stoker with a barometric damper I could see venting the gas water heater different. The 3 inch natural gas vent pipe acts as a barometric damper, sucking in room air, always opened 3 inches.

The natural gas or propane vapors mixing with coal shouldn’t be a problem. I heard mixing anything oil fired with wood smoke would be a big nfire: problem. I’m not sure what type of water heater you have(It might be propane from your pics). Its just something to think about.

Hi coal kid,

Yesterday I worked almost all day in the basement moving my hot water heater. I just bought this house in September and still have many projects to do. It's a propane water heater, there was so much sediment in the bottom it was pooping like crazy when it was heating water. I wanted to move it to give me a little better access to the back of the furnace so yesterday was the day to take it out and flush it out. I was around the stove all day so it was good to monitor what is going on. When I was loading it up, stack temp was up to 250, after everything was going, turned thermostat to 70, combustion blower shut off and the stove settled into a nice even burn. Stack temp stayed at 150 all day and distribution blower never ran and it was 72 in the house all day. Outside temp was 35-40 so I didn't think that was too bad. Last night loaded it up shook it down, topped it off. All is well. distribution blower did run through out the night. Was probably 75 most of the night, don't know what changed to give me enough heat to run the blower everything was the same as through out the day. Maybe a little stonger draft last night after it cooled off. One thing I did notice this morning was that the back grate dosen't shake down as well as the front. These grates are joined in tandem w/ a 1/2" square, back one plugs into front one and both are identical. I suspect that the slop in the connection isn't shaking the back grate as well. I cleared the back grate form underneath with the poker until I got some coals falling. Fire then picked up in the back. Next time I have things shut down I'll have to see if I can shim the connection and take some of the slop out of it. Still not sure how much to poke the fire. If someone has some advise please let me know. What I have poked it seems to be ok as long as the fire is going good. Until next time.

tim

Guys I'd be very carefule drawing the return air out of the basement. Flu gas can be draw back down the chimmney and put back up into the house. Don't think it can happen? Do some google news searches. Just a word of caution.

Don

coal_kid wrote:
The natural gas or propane vapors mixing with coal shouldn’t be a problem. I heard mixing anything oil fired with wood smoke would be a big nfire: problem. I’m not sure what type of water heater you have(It might be propane from your pics). Its just something to think about.

A word of caution NFPA 211, the fire protection code, requires a solid fuel i.e. coal appliance, have it's own chimney. No sharing of any kind. Here's the quote: "Unless listed for such connection, solid fuel-burning appliances shall not be connected to a chimney flue serving another appliance." I have never seen any coal stove manual say the flue can be shared. It usually just says a class A chimney is required.

Yanche

Yanche wrote:I have never seen any coal stove manual say the flue can be shared. It usually just says a class A chimney is required.Yanche

Yanche, I would have said the same thing until yesterday when I recieved the stuff from Pete Axeman. The Anthratube manual describes how to do it properly with an elbow on the inside of the chimney. While I would never recommend it, it appears that Axeman-Anderson feel confident their unit can operate properly with that configuration. I'm not sure if any other units would work like it , as the Anthratube is a truly different device.

coaledsweat wrote:

Yanche wrote:I have never seen any coal stove manual say the flue can be shared. It usually just says a class A chimney is required.Yanche

Yanche, I would have said the same thing until yesterday when I recieved the stuff from Pete Axeman. The Anthratube manual describes how to do it properly with an elbow on the inside of the chimney. While I would never recommend it, it appears that Axeman-Anderson feel confident their unit can operate properly with that configuration. I'm not sure if any other units would work like it , as the Anthratube is a truly different device.

That's my point exactly. Yes the Axeman-Anderson says you can do it. But how many other manufactures say so? My AHS S-130 boiler manual doesn't say any such thing. Even though it is very very similar to the A-A unit. The report from Pete Axeman is likely the most complete performance evaluation we on coal stoves, furnaces or boilers we will ever see. Coal heating is a cottage industry with no money to pay for independent testing. Much of what we get is pure marketing BS.

In a industrial setting many combustion products are commonly vented into single smoke stack. NFPA 211 permits it and gives design criteria. However it's NOT for occupied residential use.

Yanche

I agree, I would never do it. But I have seen it done and work fine. I did read somewhere that the solid fuel should always enter above/below the other unit, I just can't remember which way. Anyone remember that one?

I have just also put my forced draft on my ash pan door. I have mine on my thermostat and so far so good. I'm worried that maybe things will overheat, even though I set my limit at 150 and maybe co2 poisoning for some reason. Everything is sealed, and I have my draft damper open at about 1/4 inch gap. I may move it a little higher, but I'm still watching it. I don't know if it was the right thing to do, but it can be reversed.

I've noticed that I actually pick up draft when the combustion blower on my boiler runs. It should work fine. The only thing I think will change big from the natural draft to forced is your stack temperature. When the blower runs a long time it could easily run 600-800F maybe more so that limit is important. Be real careful if you have galvinized smoke pipe, I think it disappears around 1100F.
You should set the baro with a draft gauge to around .06.

As I said before, I put a 3 speed switch on so I can control things a little better. A couple of things that I have noticed are: 1, Now that I have a good healthy fire, I use it very little. 2, If you need to get things going in a hurry it does do the job. 3, I've been running it with the thermstat but only on the low setting, seems to do the job. 4, I think I'll change to a variable speed, medium and high seem to be the same, possible the switch is bad. A medium setting would bring things to life a little quicker and then shut down once the stat is satisfied.

I'm glad I did it. On high I have got the stack temp to about 450, I suppose you could get it very high if you let it rip. Stack temps when just idling along are 150-200 depending on how much I leave the draft open.I have been using stove coal and it's been working nice. Earlier in the week when it was cold, 0-10o, house was 70 when i got home, bumped up the stat and could get to 80 in less than an hour. Fire looks good after 12-14 hours. I'm very pleased with things at this point.

drhntr855 wrote: On high I have got the stack temp to about 450, I suppose you could get it very high if you let it rip. Stack temps when just idling along are 150-200 depending on how much I leave the draft open.

That's it, you are right there. Don't bother any more with the fan speeds, two is enough, you'll just drive yourself nuts playing around with it.

You'll find the fan a big help with a fire past its prime, just load it up as the fan will nurse it for you. No more fiddeling around.

When you guys talk about stack temp. Are you talking about the pipe temp or the gas temp. I measure flue gas temp.

Don

dirvine96 wrote:When you guys talk about stack temp. Are you talking about the pipe temp or the gas temp. I measure flue gas temp.

Don

That's right, the escaping gas, the thermo on the pipe does not read what is really happening in the center of the pipe. That's where the real action is. The best way is with a probe type thermometer right at the breech of the chimney. The stick-ons are great for a stove top, but don't give you any accuracy with inside of the stack.

I have a USSC Hot Blast 1557M stove and I tried the conversion of placing the forced draft fan on the ash tray door and using a three speed switch to control the fan. I cut the opening in the ash door to the size of the fan opening. The entire process took me most of the afternoon. I could see that there would be a problem with the input air because of the tray itself and I had already cut the back off the tray with a zip blade in a die grinder. This way I could also use the tray as a scoop if ashes fell behind the tray. Now I could leave the ash tray out of the stove during normal burn and the input air is not disturbed so that the entire grate is exposed to fresh air. I only use the blower during start up and then only if I put a large amount of new coal on the fire. This morning I put four shovels full of coal on the stove and ustilized the blower for approximately five minutes to ignite the bed. Also, I have a supply of dry oak to put an occasional piece or two on top. This setup works for me. I leave the fan cover all the way open and have been careful to watch for runaway temps or hot spots at the grate. Fortunaely there haven't been problems and I confess that I am a novice at coal burning. I'll post some pics, but it's basically the same setup as drhntr used with some small variations to make the best of what I have.
Thanks for the education. I'll continue to go to coal college until I die, because I/m getting too old to continue to cut and split like the past and coal is much easier. I like using my head instead of my back/
The goose