Pictures of a Burned Pipe and Worm Due to Improper Feed/Air

That's not good how long did it take them to find it They should of heard the grinding noise that it had to be making
and the smell of metal burning coming threw the feed tube

I think the stoker was only a week old.

That's a crime and a same some people Just don't have any common sense or for that matter no sense

coal berner wrote:That's not good how long did it take them to find it They should of heard the grinding noise that it had to be making and the smell of metal burning coming threw the feed tube

But in the defense of a new owner, when it's new you don't know what it should sound or smell like. What did the installer/plumber have to say? How good was the manufactures instruction manual? It's an excellent photo of what can happen. Will it make it's way into EFM's instruction manual as a "Don't Do This". Will it be posted on their web site? End rant.

The Installation and Operating Manual clearly states:

Due to different hardness and quality of coal, the rate of feed may have to be kept at 4 teeth or higher, in order to prevent the fire from migrating down into the coal feed tube during long periods of standby due to warm weather or low demand.

The following, in bold print:

If excessive heat is detected on the aluminum coal pipe outside of the boiler jacket, the rate of feed should be increased immediately to keep from damaging this pipe or other components of the pot assembly. Also, check rate of air for possible problems.

Checking the temperature of this pipe should be done on a regular basis.

Whenever the coal feed rate is adjusted, the air setting must be adjusted also. These…settings…may have to be varied to suit the particular type of coal being used. It may be necessary to adjust the air supply several times until the desired setting is attained.

The following, in bold print:

With a properly adjusted fire, there will be an ash ring approximately 2” wide around the outside of the burner with a small circle of coal at the center of the fire.

With too much air, the fire bed will tend to develop cracks, the ashes will clinker and the dark spot at the center of the fire will disappear. With too little air, the ash ring will be very small, hot and dark off the burner ring into the ash pit and the dark spot at the center of the fire will be large.

Fines Cleanout

To prevent fines accumulation in the burner air chamber and costly repairs, the cleanout lever must be pulled back and held in that position (with stoker operating) for 15 seconds, once every day.

It’s very obvious from these instructions that daily attention is required for a coal stoker. A visual inspection of the fire is necessary until the proper feed rate and air settings are achieved. Anytime there is a change of coal supply, the owner should be checking the fire for proper operation.

In the case of this burned worm and pipe, was the owner following the instructions in the Operator’s Manual? Did he notice an odor of burning paint and investigate? Was he checking his stoker daily?

Coal heat offers great savings but requires some observation and effort on the part of the owner. This caveat would also apply to all other forms of heating, especially with regard to odors.

As always, our dealers, and we at efm are always available to speak with, concerning our stoker’s operation, especially when a new owner is learning the art of coal burning.

Why is the pipe made out of aluminum instead of steel? Also, what are the holes in the top of the pipe for?

e.alleg wrote:Why is the pipe made out of aluminum instead of steel?

To prevent corrosion could be one reason, I've seen the ends of pipes in coal bins completely corroded out on steel pipes that have been there for 25 years or more. That's going to get the double whammy, any moisture in the coal plus sulfuric acid if it's left to sit over the summer.

stoker-man wrote: To prevent fines accumulation in the burner air chamber and costly repairs, the cleanout lever must be pulled back and held in that position (with stoker operating) for 15 seconds, once every day.

This is probably the most neglected thing on the 520. Why does the 520 have the manual fines cleanout? The 700 & 900 did it automatically for you. I think the 700 & 900 were a superior design and yet they were discontinued.

stoker-man wrote: It’s very obvious from these instructions that daily attention is required for a coal stoker. A visual inspection of the fire is necessary until the proper feed rate and air settings are achieved. Anytime there is a change of coal supply, the owner should be checking the fire for proper operation.

In the case of this burned worm and pipe, was the owner following the instructions in the Operator’s Manual? Did he notice an odor of burning paint and investigate? Was he checking his stoker daily?

I think this is the best argument against an automatic ash removal system. Having an ash pan that requires you to remove every day or couple of days at least forces someone to look at and be near the boiler on a somewhat regular schedule. We should not become complacent with any automatic coal fired boiler. You should be able to trust it but also verify that it is functioning properly.

gaw wrote: I think the 700 & 900 were a superior design and yet they were discontinued.

What is (are) the differences between the 520, 700, and 900? I see the manual for the 900 on the EFM site. Looks like a nice boiler/stoker. I do notice the right angle bin feed vs. the thru the back setup of the 520. What are the respective specifications of each unit?

Chris

e.alleg wrote:Why is the pipe made out of aluminum instead of steel? Also, what are the holes in the top of the pipe for?

In the beginning and for a short time, a brass pipe was used. Shortly after, in the '50s, the pipe was made from aluminum. Richard gave a great answer. Also, from wet coal and the heat from the pot, the heated mosisture would quickly corrode the steel pipe. From being unused in the summer, the two similar metals would corrode/rust together and could not be taken apart.

The holes in the pipe, which are meant to face upward, are to safely vent any coal gas back into the combustion area. Many people use only the short pipe and feed from a 55 gal. drum. This can result in coal gas being forced back in the pipe and out of the drum into the air. For this reason, it is necessary to use both the short and the long pipes for safety. We realize that this isn't always done.

europachris wrote:

gaw wrote: I think the 700 & 900 were a superior design and yet they were discontinued.

What is (are) the differences between the 520, 700, and 900? I see the manual for the 900 on the EFM site. Looks like a nice boiler/stoker. I do notice the right angle bin feed vs. the thru the back setup of the 520. What are the respective specifications of each unit?

Chris

I'm not sure where you saw the 900 on the website ????? The 520 is the only stoker produced now. The gross BTUH output is 220K and the net output is 186K. It has a wide range of BTUH output, depending upon how much coal is fed.

The 700 and 900 models are still available as used models and many parts are available. Mark's in Shenandoah, PA is one who has this end of the line.

I questioned our two 40+ year vets in this business about the frequency of pipes burning. Both agreed that it was extremely rare and always from owner neglect. It sometimes happens after an owner gets a load of new coal from a new supplier which may not be the same quality as a previous supplier. Sometimes, owners will not clean the ashes and they build up around the pot after filling the entire base and the stoker now becomes a forge. Also, the inexperienced owner is not watching his pot.

A stainless steel bin feed and burner end pipe is available for users who want a long pipe life. I think they are worth the small additional price.

For those who cannot maintain a coal fire or empty ashes because of vacations, etc., an optional oil burner kit has been available for about the last 30 years.

Does the optional oil burner work with the coal furnace? If the coal fire goes out the oil automatically kicks in or is it a conversion?

billw wrote:Does the optional oil burner work with the coal furnace? If the coal fire goes out the oil automatically kicks in or is it a conversion?

To switch from coal to oil requires a manual action of opening the damper assembly and setting the electric switch. It's a fail-safe method so that both fuels cannot run at the same time. This is an optional burner which can be retro-fitted to any boiler that uses the square fire door.

As long as your coal bin contains coal, the fire should never go out. It's a fully automatic system.

The coal stoker furnace, re-introduced in 2006 does not have the oil burner option.

I'm using the DF520 and I had to shorten the feed pipe. My pipe is 3 feel from the boiler. I have it feeding from a small bin. My pipe is heating up and I am getting a gas smell. I undertand what is happening. The coal in the bin is heating up. I don't really have the room to extend the pipe. Any suggestions? I've increased the feed and air flow. My air flow is set about 5 is that to much? The flame appears good. I'm new at burning coal.....HELP. I do have the oil set up. So until I am more familar....I burn oil at night so I can monitor the coal burning during the day.