BACK DRAFT !!

[machinistbcb]

I am getting a rather serious back draft ( I think that's what you call it ) on my 2000 series Tarm gasfier. Tonight I openend the bottom door to check for proper gasifacation and I got a big rush of air, smoke, and burning hot ambers in my face. No harm done to me but I wasn't happy about filling my boiler room with red hot ambers. I also noticed it with the door closed. I could hear a big rush of air and smoke would blow through the draft fan. Is my problem likely due to improper draft ?? My chimney probably should be taller, its about 16' of of 6" class a pipe. Would a draft inducer help ? It would be much easier for me to add a draft inducer than add longer pipe as my chimney comes out through a tall metal roof on my barn and I really cant reach high enough for another length. Any thoughts?

Thanks,

Brian

 

[jebatty]

I would check to make sure you are supplying adequate fresh air in your boiler room to meet air requirements. You needs lots of input air available to get a proper draft. Next, review your chimney top in relation to roof peak, trees, obstructions, ambient air turbulence, etc. Third, does this happen all the time or only sometimes? Often in warmer weather it can be more difficult to get a good draft than in colder weather. Also, certain wind conditions can affect draft.

Chimney height does matter, and it's possible that 16' is a little low.

 

[deerefanatic]

I know that the 6 foot chimney I've got on my Outdoor Gasifier I'm building won't draft at all until the chimney gets warmed up........ I can always tell because there's a small hole drilled in the base of the chimney that I can peep through to see if flames are coming out the bypass.... When cold, the smoke pours out this little hole..... Once the chimney warms up, the smoke stops coming out...

Try cracking a window open and seeing what happens.... Also, try warming the chimney, on one that short, it might help you......

 

[heaterman]

I would suspect a lack of combustion air also.

 

[machinistbcb]

Doesn't really seem to make a difference with the boiler room door is opend or closed, but I have been suspect of the combustion fan be faulty. It seems to lack power and when I turn the fan on it wont start unless I give it a spin with my hand. Could the fan possibly be not moving enough air into the combustion chambers ? Any body know what RPM the tarm fan should spin at ??

 

[Duetech]

I can't tell you the rpm of the motor but it should be on an ID plate on the motor if you can get to it. My EKO 40 varies the speed depending on the phase of the burn related to boiler temperature. Your fan may just need lubing or there may be something obstructing rotation. To be on the safe side you may want to research a replacement for it because it sounds as if it's about to seize up...Cave2k

 

[jebatty]

The Tarm draft fan purrs right along at a good speed, should start right up. I had to close the damper quite a bit on mine because the draft was too strong.

 

[machinistbcb]

I can’t tell you the rpm of the motor but it should be on an ID plate on the motor if you can get to it.

Yeah, none of the writting on the id plate is in english. I have already lubed it, and seems to spin quite freely to me. I think it's more of an electrical problem, I have the fan damper opened all the way up. I guess I might have to bite the bullet and buy a new fan which I am sure is not going to be cheap coming from tarm. If any body is local to Sabattus, maine and has a tarm I would love to be able to come check your fan out to compare it to mine. I have a strobe tachometer that I can check RPM's with.



Brian

 

[DaveBP]

Brian, try spending the short money first and swap out the capacitor on the fan. Mine is on the outside and easy to get at. Don't know about the older ones. Grainger's have a storefront in LA? They'll have one. My Tarm 40 uses a 6uf. Radio Shack? Any electric motor that needs to be kick started is pretty dubious but a new starter cap is sometimes all that's needed. Might make it run better after it's running up to speed, too.
I'm out here 30 or so miles west of the Gray turnpike exit. Let me know if you feel like making the drive, but I'd try that capacitor first if you can find a replacement. New starter caps have saved my cheapskate butt a couple times.

 

[deerefanatic]

I agree. I have a PSC (Permanent Split Capacitor) motor on my blower. Without the capacitor, it won't run. Just hums.... Even if you give it a good start by hand, it runs real weak and even stops eventually. New caps are really cheap at any electric motor shop.

Now, if the blower is a shaded pole type, then there wont be a capacitor on it. Then it's probably new motor time. You will know because the capacitor will either be attached to the blower housing and wired to the motor with two wires, or attached to the motor itself with a little cover over it.

 

[machinistbcb]

You guys were right on. I took the capicitor off today and it was busted up- and toasted. It's made by Jenson out of Denmark, I did a search but I can't really find a supplier in the U.S. I think graingers should be able to give me one simular. Thanks for the help, hopfully this will fix the draft problem.



Brian

 

[deerefanatic]

Check your local electric motor shops first... They may just have one.......