EFM Stoker-issues

Hello All

I bought a house a couple years ago with and EFM stoker in Northeastern Pa (right in coal country). It worked like a charm until just recently. For some reason the fire wants to go out. I found out the only time it kicks on is when triggered by the thermostat. I understand there is a timer that is supposed to periodically turn it on at a specified time. The brand of timer I currently have is Will-Burt. How often is this feature supposed to turn the stoker on? I am thinking that is my issue considering it will not fire at all until the thermostat drops below temp. Any ideas?

Other questions
What is the pressure gauge supposed to read for a steam system?
What are the proper setting for airflow and coal feed? Any feed back would be great...I am trying to learn as I go. I am not sure if this depends on size of heating area.
What does the aquastat control?
What is causing a very loud banging in the pipes as they heat? Can this be avoided.

After seeing these things go to work, I really want to learn more about them. They are great units and I wish I had more info about them. I hope I came to the right place!

Something isn't right, either the blower or stoker isn't getting the nudge it needs. It could be just chocked up on flyash and starving for air?

The steam pressure can vary by the systems design, but if it is heating the house it is enough. I would not want to go more than 25-30#, 10 or 15 is probably more than enough.

The aquastat controls the boilers operating temperature and may control other functions too.

The noise is from the steam (very hot) meeting the cold water in your pipes. This is a "hell on earth" scenario inside the pipe, it can make a lot of noise.

If I were you, I would convert the system to hot water. It will be nice and quite and cheaper to run.

Can't help you with set points, see the EFM guy. Do you have a manual for it? It is posted I believe in the EFM section.

With respect to your timer it should run the unit based on the settings on the dial. Usually (IMO ) 4 to 7 minutes every half hour. Based on what you are seeing I believe the timer is not functioning properly, sometimes the clock motor goes bad (since it runs 24/7) and is usually a replaceable unit. Although the EFM support guy can tell you for sure, since this was moved to his domain, he should be chiming in soon.

In the mean time you might try increasing the time on the dial and see if you can get it to go on. Be careful not to overfire it though, so what ever you try make sure you will be around to check on it regularly.

mmeck wrote:How often is this feature supposed to turn the stoker on? I am thinking that is my issue considering it will not fire at all until the thermostat drops below temp. Any ideas?

I guess their might be different setups and I'm not familiar with steam but this is how a ours is setup. The aquastat has a high and low limit, the furnace will come on if it hits the low or stop stoking if it hits the high. These are set at 140 and 180, note this is hot water system and not steam. The timer will run the furnace for about 3 minutes every hour, you can vary this by adjusting the timer. This is really not needed in the winter because you should have plenty of demand for heat that it doesn't go out.

What is causing a very loud banging in the pipes as they heat? Can this be avoided.

Again not I'm not familiar with steam but I did see a "Ask this old house" feature on banging steam pipes. This particualr system used the same pipe to supply the steam to the radiator and act as return once it condensed. The banging was caused by the radiators having an incorrect pitch for the condensed water to fully evacuate the radiator.

http://www.efmheating.com/manuals/DF520%20Manual.pdf here is the manual. The timer will run the stoker 2-3 minutes every hour in the summer to maintain the fire when there is no call for heat, it doesn't do much of anything in the winter but I'd leave it hooked up - better to wear out than rust out. I heat 4,000 sq. ft with 5 teeth on the stoker and the air pointer a little above 4. To check the teeth you really must shut off the power and turn the shaft by hand and count the clicks, it's almost impossible to do it accurately when the thing is running. Read the manual where it talks about the ash ring and black spot, it takes a few tries to get the air setting right. If it's wrong you'll know it there will be 50% unburnt coal in the ash pan. The aquastat is difficult for me to understand, Honeywell has the manual online. Have fun with it, I get a headache reading it. The EFM manual above has the aquastat settings for steam. I think you should only be at 1 or 2psi for steam, but again it all depends on your exact system. I would learn all you can about it as a good plumber that understands steam is hard to come by, they were all the real old strong looking guys we remembered as kids.

I found out the only time it kicks on is when triggered by the thermostat. I understand there is a timer that is supposed to periodically turn it on at a specified time. The brand of timer I currently have is Will-Burt. How often is this feature supposed to turn the stoker on? I am thinking that is my issue considering it will not fire at all until the thermostat drops below temp. Any ideas?

Your boiler temperature is controlled by the aquastat and the Will-burt timer, along with the thermostat.

I am not as familiar with steam as I am with hot water.

Your timer should be set to force the boiler to run 3 minutes per half-hour. This feature doesn't usually come into play in the winter because you have enough demand from the thermostat. Your aquastat should force the boiler to come on when the low limit setting is reached, minus the differential setting, if there is one with steam. Other rules apply to hot water systems.

What is the pressure gauge supposed to read for a steam system?
What are the proper setting for airflow and coal feed?

Your pressuretrol should be set at 1 1/2 pounds. Your relief valve is 10 pounds.

You have to experiment with your air and feed for coal. If the coal quality is good, you might want to start with 5 teeth of feed and 5 air. You are looking for an ash ring that is about 1 1/2 inches wide and not very high above the burner ring plate. When the stoker shuts down, you should see a dark spot in the center of the pot. This is fresh coal. The rest of the pot will be orange/red.

We have seen several cases of improper settings, such as too much air or too little feed, where the fire has burned down into the bottom of the pot and into the coal pipes. One such fire burned off about 8 inches of pipe and worm and pulled the pipe right out of the coal bin. In two cases, the owners had bought some "cheap coal" and weren't watching their pots. One of the units was a brand new stoker.

If you feel the burner end pipe, where it exits the jacket, it should never feel hot or even very warm. If it does, you are burning too deeply into the pot and everything will be ruined.

Banging in a steam system has several causes. Dirty water in the boiler causing wet steam and/or return lines that are not sloped downward and the condensate is preventing the steam from passing by. Especially check your radiators. From settling in the house, they have often lost their pitch in the piping.

Jim, our steam man, is usually at efm on Mondays all morning from about 8 until 1 pm. Call efm 610 965 9041 and ask for Jim about efm steam boiler questions.

Stoker man, do you have any pictures of what a good coal burn should look like? What will it look like if there is too much or too little air?

I'll see what I can do.

The best book for learning residential steam heating systems is "Lost Art Of Steam Heating" by Dan Holohan. Buy it. Well worth the $40.

http://www.heatinghelp.com/shopcart/pro ... tegory=2-3

mmeck wrote:Hello All

I bought a house a couple years ago with and EFM stoker in Northeastern Pa (right in coal country). It worked like a charm until just recently. For some reason the fire wants to go out. I found out the only time it kicks on is when triggered by the thermostat. I understand there is a timer that is supposed to periodically turn it on at a specified time. The brand of timer I currently have is Will-Burt. How often is this feature supposed to turn the stoker on? I am thinking that is my issue considering it will not fire at all until the thermostat drops below temp. Any ideas?

!

Your efm stoker steam unit will maintain a minimum water temperature by control of the L4006 aquastat. It's set to maintain a temperature for household hot water. When the boiler temperature falls below this limit, the aquastat will tell the stoker to start up and bring it back up to the minimum temperature. In the summertime, your timer will force the stoker to run every half hour to accomplish the same thing.

The other way for the stoker to start up is by the thermostat. On a call for heat, 24V will go from the tstat to the timer relay and cause 110V to flow to a low water cutoff, if you have one, or to the pressuretrol and then to the stoker motor. The pressuretrol is a NC, normally closed contact and will open, shutting off power to the stoker, when the pressure is above the set point, usually 1 1/2#.

Check your water level after the stoker has been at rest for a moderate period of time, NOT when it’s running or shortly thereafter. The circulator must also be OFF. The water level should be high enough at rest to cover the hot water coil. This would be 46 ½” measured from the bottom of the base.

Some other info about your steam boiler: If you are getting banging in the pipes, one reason is dirty water, causing wet steam. On the efm boiler, you can skim the water through the water glass port. Skim several times until it’s clean. You can also add an emulsifier to the water to dissolve any oils, which will then fall to the bottom of the boiler.

Periodically, open the drain to drain a small amount of water/sediment out of the bottom of the boiler.

Banging can also be caused by firing too high, causing the water to come to a boil too quickly and improperly pitched pipes, especially near a radiator that has settled.

The guys thus far have offered great advice on you EFM steam boiler. Bad water will indeed cause banging in the steam mains. Also, you may want to check any air valves you have in the cellar on the return mains. If you have wet returns, these would be located (if anywhere) on the elbows above the vertical drops. Most homes have these. Particularly on larger homes. If these are plugged or bad in general, air won't be able to exit the system and the steam will push any water against the air and that in turn will work back and forth on the system causing problems in the steam main and returns.
One big mistake people make and usually affects the heating system in spring and fall is by taking the insulation off of the steam mains just down stream from the boiler in order to heat an otherwise unheated room. This will cause the low-flow steam to condense in the supply main and bang up against any elbows it encounters. The steam will condense quicker and cause any dry returns to fill up with water since the boiler is running and affectively putting a "back pressure" against the return main so the water won't flow back to the boiler. Insulate any supply mains that need it. If there's insulation falling off, be very careful because it's likely asbestos and very friable. If you HAVE to remove it, wet it first with a combination of water with some dish washing liquid mixed with it to keep the lose fibers intact while you do it. Wear protection too.
Now, as to the other thing, you should only carry about 1-4 lbs. of steam pressure when the system is actually calling for heat. In some instances, it may be merely onces of steam you want. You should only be heading up the amount of steam necessary to satisfy the heat demand and no more. Under no condition should you attempt to raise the steam pressure setting.
The others came up with great advice. You water could be bad. I'd blow down the boiler to see what sediment you get if any. You might have mud in the bottom of the boiler. If this is the case, it should have the fire stopped and the boiler flushed out since this could lead to burnout because it will impede the heat transfer on the bottom of the boiler.
Write back and describe your system....such as one pipe or two pipe, pipe size and any other relevant information. Then everyone can help you a bit better.
Doug