Oil to Old EFM

Stoker Coal Boilers automatically feed the coal and have controls and pumps just like any conventions boiler. They are intended to be used as a primary heat and often have domestic hot water coils as an added bonus. They can be set up independently or in dual sytem with your existing oil/gas boiler. They can accommodate both hot water base board or steam plumbing.
427adam
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Posts: 10
Joined: Mon. Oct. 14, 2013 11:53 am
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: Somerset, PA

Post Sun. Oct. 27, 2013 1:32 pm

Hello,
I am in the process of educating myself while working toward replacing an oil boiler with an older model EFM 520 (I think) I have been reading as much as I can on this forum and have learned a bunch. Thank-you to all those that have contributed for the benefit of others!

The space I am heating is a garage/workshop 3520 sq. ft. pole building construction radiant in floor heat. The building is fairly well insulated (R30 in ceiling, R12.5 walls) but does have three garage doors facing the wind/storm side.

I am not an extremely knowledgeable person when it comes to HVAC, but would consider myself a pretty advanced DIY kind of guy. I can follow blueprints and schematics (machinist / fabricator by trade) I would be grateful for some guidance from those that have been there, done that and have a 20/20 hindsight.

I am not sure how old the boiler is. The name plate is there, but no numbers are readable.(rusted) Looks like the domestic coil had been leaking. After removing the coil, I replaced that section with a piece of 3/8” boiler plate large enough to cover all areas of thin metal and made a second 3/8” thick blank cover plate. The other areas of the boiler look to be in very nice condition. The base is all there but needed some new metal at the bottom of the “smoke box” (below the flue outlet)

The stoker is missing a few small miscellaneous parts (check pawl and offset pin ect) but was disassembled, cleaned and inspected. Only issue I found was the shear pin hole in the clutch shaft is eggshaped and will be replaced. Is the clutch shaft stainless?

I plan to use bagged coal and a 55gal drum as a hopper for this heating season and if all goes well, work on something more cost effective next summer. I see that most people have their drum (or hopper) located inside. Would I have any issues keeping the drum outside under an attached shed roof?

The only real option I have for chimney is insulated stainless. The spent gasses will exit the boiler, run through a 90 elbow, then vertically about 7’ Then another 90 elbow through the side wall connecting to the branch side of an insulated tee then vertical through the shed roof (above the coal drum)

The missing pieces should be here in a few days. I am hoping to pressure test the boiler, and complete a test burn within the week.

Any comments, suggestions, or advise is greatly appreciated… Pics will soon be following!

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Rob R.
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Posts: 11360
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Sun. Oct. 27, 2013 6:00 pm

Welcome to Nepacrossroads.

If you haven't already, browse through the pictures of the EFM clutch assembly so you are familar with everything: viewtopic.php?f=55&t=6126

I have never seen the hole for the shear pin get worn, but the hole at the opposite end is often worn egg-shaped. The hole can be worn and still function fine, so use your judgement if it needs to be replaced. Sometimes a larger cotter pin will tighten it up nicely; in that case drill out the auger coupling as needed to accept the larger pin.

Plan on piping your boiler with a primary/secondary arrangement, that way it won't be slammed with cold water from the radiant slab.

Mark (PA)
Member
Posts: 383
Joined: Thu. Feb. 28, 2008 9:40 am
Stove/Furnace Make: 1953 EFM SF-520 High Boy
Stove/Furnace Model: Fitzgibbon Boiler
Location: South Central, PA

Post Tue. Oct. 29, 2013 8:10 pm

If you do not do primary secondary loops on your piping as rob mentioned be sure to use BOTH Boiler Inlets on the rear piped to a Tee that goes directly to your FEED outlet to your system. Valve in the center and set it to half open to help mix in the hot water leaving your boiler and cold water coming in from your zone(S).

My auger sheer pin hole was also worn. As Rob said. Larger Cotter pin should help solve that wear.

Mine is pretty well worn when I got it but functions just fine.

Good luck. ask questions if you run into anything

Mark (PA)
Member
Posts: 383
Joined: Thu. Feb. 28, 2008 9:40 am
Stove/Furnace Make: 1953 EFM SF-520 High Boy
Stove/Furnace Model: Fitzgibbon Boiler
Location: South Central, PA

Post Tue. Oct. 29, 2013 8:14 pm

Just noticed you are from Somerset PA.

I live in Bedford Co myself... There is another guy Buffalo bob from Manns Choice area.

427adam
New Member
Posts: 10
Joined: Mon. Oct. 14, 2013 11:53 am
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: Somerset, PA

Post Thu. Oct. 31, 2013 12:06 am

Thanks for the replies. Great to hear there are a couple guys close enough to check out some other 520's when (not if) I get stuck!

I pressure tested the boiler at 60 psi and have zero leaks. Hopefully the parts I need to make a test fire will arrive tomorrow. If that is the case and we can build a fire in the pot, we can stack the two parts together! :D

Looking forward to some plumbing and wiring. As recommended, I plan to plumb the return back into both lower ports. On the right side, there is a 3" x 1/1/4" bushing. On the left side, there is what appears to be a factory installed 3" x 3/4" bushing...or at least installed a LONG time ago. I didnt try very hard to take it out, (only a 24" pipe wrench and no heat) but it's most definitely tight. Should I do whatever it takes to replace that bushing with an 1 1/4" NPT or would one 1 1/4" joined with one 3/4" return suffice?

Havent forgot about posting some pics. will get to that...maybe during our test burn.

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Rob R.
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Posts: 11360
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Thu. Oct. 31, 2013 7:24 am

I would pipe the returns with equal size fittings, other wise you will have uneven flow...and that defeats the purpose of using both returns. A 24" pipe wrench is not enough, look for a three footer or larger. I have had excellent results using three wraps of Teflon tape and GRRIP pipe dope on threaded fittings. 4 EFM installs and not one leak using that combination.

FYI, the return ports are 2", outlet on top of boiler is 3".

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stoker-man
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Posts: 2063
Joined: Mon. Nov. 19, 2007 9:33 pm
Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
Coal Size/Type: Anthracite/Chestnut
Other Heating: Hearthstone wood stove
Location: Lehigh Valley, PA

Post Sat. Nov. 02, 2013 8:22 am

You would need a sawsall or hacksaw blade and a punch to remove the bushing like I did.
Attachments
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427adam
New Member
Posts: 10
Joined: Mon. Oct. 14, 2013 11:53 am
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: Somerset, PA

Post Sun. Nov. 03, 2013 8:50 pm

Thanks to Kroil, heat, and an impact wrench, I avoided having to cut the bushing out. I didnt make as much progress as I had hoped this weekend. No test fire yet...maybe one evening this week???

In the mean time, here are a few pics.
Attachments
DSCF1331em.jpg
DSCF1332em.jpg
DSCF1330em.jpg
Close up of DHW panel repair
DSCF1335em.jpg
DSCF1336em.jpg
Soon ready for furnace cement!

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Rob R.
Site Moderator
Posts: 11360
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Sun. Nov. 03, 2013 8:55 pm

Looking good so far. Someone did a beautiful job repairing the tankless coil area.

427adam
New Member
Posts: 10
Joined: Mon. Oct. 14, 2013 11:53 am
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: Somerset, PA

Post Sun. Nov. 03, 2013 9:05 pm

Thanks for the compliments Rob. I made sure the repair panel was large enough to cover all thin areas left from who knows how many years of gasket leakage. I ground a full vee around the perimeter of the repair panel and the boiler opening. Ran two passes allowing some time to cool (minimize warpage) I also went with 3/8 cover instead of the 1/4 that was on the domestic coil. I thought nyloc nuts may help keep things sealed up a little better than a standard hex nut.

Welding and machining are some of my strengths, plumbing is an area where I need lots of advise! :)

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Rob R.
Site Moderator
Posts: 11360
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Mon. Nov. 04, 2013 5:18 am

I would skip the lock nuts. You want to be able to "feel" how tight the mounting bolts are so that you don't overtighten it and break the gasket. The nuts don't back off, the gasket looses its elasticity over time. I like to snug things up for the initial install (you will see the gasket squish out slightly between the studs), and the first time the boiler cools down after the first firing, check them again.

427adam
New Member
Posts: 10
Joined: Mon. Oct. 14, 2013 11:53 am
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: Somerset, PA

Post Sun. Nov. 17, 2013 7:52 pm

IMG_8714em.jpg
Have been making some progress lately. Plumbing finished, coal in the bin (and barrel)

427adam
New Member
Posts: 10
Joined: Mon. Oct. 14, 2013 11:53 am
Stove/Furnace Make: EFM
Stove/Furnace Model: 520
Location: Somerset, PA

Post Sun. Nov. 17, 2013 7:52 pm

Yesterday, (Saturday)was the big day. First attempt to make some hot water with hard coal. Only had to wire / install the aquastat and timer, fill with water, and light a fire.
Attachments
IMG_8715em.jpg
Last edited by 427adam on Sun. Nov. 17, 2013 7:55 pm, edited 1 time in total.

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KLook
Member
Posts: 3636
Joined: Sun. Feb. 17, 2008 1:08 pm
Stoker Coal Boiler: Harman VF 3000
Coal Size/Type: rice, bagged, Blaschak
Other Heating: Gas boiler backup/main
Stove/Furnace Model: VF 3000
Location: Chattanooga, Tenn

Post Sun. Nov. 17, 2013 7:55 pm

Thats a mighty fine looking job on your setup for a guy needing help with plumbing. Congats and enjoy! :cheers:

Kevin

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Rob R.
Site Moderator
Posts: 11360
Joined: Fri. Dec. 28, 2007 4:26 pm
Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy
Location: Chazy, NY

Post Sun. Nov. 17, 2013 8:09 pm

I am having a hard time figuring out the piping. What is that huge circulator doing?

If you call around you can probably get an original EFM door for the front of the boiler.

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