AA-130 MOTOR PULLEY SIZES

What is the factory original motor pulley size opposite the fan pulley?

What is the factory original motor pulley size opposite the auger gear box pulley?

And, has anyone ever experimented w/ changing either size?

I flipped the fan and motor pulleys, it wasn't happy.
Some people play with the feed tube speed, slowing it down makes it a little less melodious and perhaps a little less wear. But this comes with some risk as it would run low if not feeding enough. Overdriving it will only make more noise and wear. I wouldn't bother with it, seems to me they would have changed something in the 65 years if it would have made it better.

I'm going to go measure mine later, the local hardware store had a bunch on clearance, slow movers i guess. They were made in the USA, so they are older, maybe better. Can never have enough spare parts.

Try to get the steel or cast iron pulleys only. The alloy ones are not designed for continuous service........but they are cheaper...made in someplace other than the USA. The feeds rates WERE experimented with and back in the day Bethleham, Penn State and AA all had MANY slick solutions....all too expensive for the average Happy Homeowner. Variable frequency drives allowed for incredible efficiencies, as did ash manipulation, HOWEVER, a laboratory setting is FAR different from a basement with water running through it...some wet coal and fines plugging the feed tube, SO the AA we have today is still the finely crafted bulletproof ROCK of a boiler. It may look a little odd, but I'll take function over form any day. The basic premise individuals need to understand is that: 'It is not a perfect world, however we do the best we can'!

My friends down at Blue Ridge Diesel say it this way: 'The happiest of people don't necessarily have the best of everything; they just make the most of everything.'

McGiever wrote:has anyone ever experimented w/ changing either size

Yup... Axeman Anderson did for years!

Thanks all for the replies!

As far as the experimenting w/ pulley size question, what I really am looking at accomplishing is to lower the 130K btu/hr output some.
So, the fan speed is where I was looking to change. The auger tube/ashing side I was thinking of just letting it be.

My thinking is there should surely be some *wiggle room* for speed adjustment when it comes to fan air, as any variety of pea coal from the many different breakers would allow a different volumes of air to be pulled through the fire pot.
Axeman, I'm sure, did their best to be able to consistently achieve the advertised 130K output w/ the variety of pea coal from different breakers. I only want to take the output down...that should not be reinventing the wheel.

More air = more heat (within certain limits)
Less air = less heat (within certain limits)

If I could obtain...say...100K BTU/HR, I'd be happy.

I think you would be looking for a reduction in the size of the fire. A insert or a block off might work. Reducing the fan speed you would probably reduce efficiency and "reaction" time.

McGiever wrote:I only want to take the output down.

I've had the same thought. The only way I can think of is make the fire chamber smaller, but that's no easy task.

What do you hope to achieve with the reduced boiler output?

For me it's the hope of better efficiency. The AA's have legs.... they like to run! If you make them slow to a walk they just don't burn as well. In warm weather you get a certain amount of unburned coal in the ash. So, if it were 80,000 BTU instead of a 120,000.... it might just use less coal.

Freddy wrote:For me it's the hope of better efficiency. The AA's have legs.... they like to run! If you make them slow to a walk they just don't burn as well. In warm weather you get a certain amount of unburned coal in the ash. So, if it were 80,000 BTU instead of a 120,000.... it might just use less coal.

$0.02 from an EFM guy. If you reduce the fan speed you may trade one thing for another. The first thing that comes to my mind is fly-ash buildup in the heat exchanger area. The touted self-cleaning feature of the AA depends on a high velocity of the flue gasses. I believe forum member gregolma tried this once before and experienced a lot of ash buildup. The guys that designed this beast surely understood the compromise between mechanical wear, ash buildup, and efficiency...so I bet the pulleys they settled on weren't the first set they found in the stockroom.

Perhaps a slight reduction in fan speed would increase run time a little without causing ash buildup? You seem like the perfect guy to conduct an experiment.

As for the unburned coal in the ash, I think it is the tradeoff of combustion efficiency vs. thermal efficiency. I bed if you lined the combustion tube with some kind of ceramic material like the baseburner guys (I have my base burner (BB)) you may get better burn-out of the coal...but it may impact the amount of heat transferred in that area.

The best way to reduce it's output would be to cast a refractory ring and slip it up into the fire pot. Holding it up there may be an interesting problem.

I agree that reducing fan speed isn't the answer..... My only idea was to decrease the burn chamber size and as Coaledsweat mentioned, doing that poses interesting mechanical challenges.

The possibility of making the fire chamber smaller is tough due to the extreme heat created, AND the need to scrub it off through transfer to the water jacket. 130K is a conservative rating, and since no one has stepped forward to build a 80-90K new boiler, my .02 says heat something else in or around you home. Like a warm basement? Garage? Patio floor? Roof radiant for Ice melt? Driveway radiant for safer winter walking? Most folks who know little or nothing about solid fuel heating are like the Soup Nazi from the Seinfeld days. It does not cost more to enjoy more. For 10 years I have enjoyed a winter patio on the north side of the house that melts 16' by 16' at no apparent extra use of fuel for the safety and comfort we derive. It is a dump zone in times of need (hasn't occurred yet, but is wired and tested) . I burn 24/7-365 so there is no excuse to not be prepared. Frequently several AA's a hooked up while being tested, so it is like a load bank on a generator. 4- 260's all at once idling makes some extreme heat.

Once again, I don't recommend that you try to outsmart the original engineering, these rigs aren't EFM's or Keystokers.

Well, the consensus is in...

If it ain't broke...no sense fixing it till it is broke.

Sometimes you just have to Suffer in Luxury.

There are areas at home here where I can expand the system to up the load for the Axeman-Andeerson