Rebuilding EFM DF-520 Project

gwjwbw wrote:All the trouble I went thruto get the nuts off and broke 3 out of 8, it be alot easy to have a flange weld in, I rather cut the nut and bolt out thru break another stud, anyway, thank for letting me know about the coil size, Gerard

coal berner wrote:

gwjwbw wrote:The opening on the boiler for DHW coil, I have a 5 gpm coil now and going with a 7gpm, do I need to make the opening bigger?
I snaped off 3 of the 8 bolts that hold the coil, now going to cut them all out and weld a flange onto the boiler and use nut and bolt for the coil
Gerard

Why not Just drill out the broken studs and re thread the holes and put new studs in then there is not need for a flange
and either size coil will fit right on .
Should of put the studs on the New parts list .

Well it it your do what you want Just make sure the welder knows what he is doing .
BTW The efm boiler is 5/16" boiler Plate steel not Just plain 1/4 " steel plate .
Remember you dealing with a hot water pressure vessel Be Careful Make sure someone knows what there doing.
Make sure you make the flange the right size so the coil fits bolt pattern

coal berner wrote:First Chris you still have to take the pipe off to clean the pipe out so while the pipe is off for cleaning it is not hard to stick a vac in the base to suck out fly ash so there is no reason to put a clean out door on the base Just another place for air leaks that yo have to seal up.

Every application and setup is different, I suppose. My flue is straight up after the bend out of the base. I just give it a few taps and the fly ash and soot falls down to the elbow. Then I reach in through my cleanout and brush it into the bottom of the base so I can scoop it out. What is nice about having the cleanout is that the flue is still connected while I'm brushing out the tubes so all the fine particles get sucked up the stack rather than blowing out into my face and the boiler room. It makes for almost a zero mess operation. This is important since I have to clean out more often burning bituminous as well as the soot being far more messy than just plain fly ash.

coal berner wrote:Second he has a DF 520 which is not a tube boiler it is a flat plate heat exchanger by going thur the Frontr SQ door he can remove the baffle plate that hangs in there and remove the two back plates off the hooks now the whole back of the boiler is open you use a horseshoe boiler bush to clean in between the heat exchangers plates and like I said before if you use a 1 1/4 hose on the shop vac with a hose attachment or two you can clean out the flue breach thur the front door and the bottom of base now if you keep up with maintenance every year there will be very little ash in the bottom back of base most of it will be in the flue pipe hooked up to the back of the base .
Which is why you need to take it off anyway to clean it out so you have two ways of cleaning the base out front or back.

Point well taken, J.C. I'm not familiar with the innards of the 520 boiler, although I do know that they take additional baffles that my 350 does not. I've only seen a picture of the mounted baffles looking through the firedoor and couldn't really tell how it all went together. LIke I said, I've got a unique perspective since I am likely the only one on the planet with an underfed bituminous burning EFM 350 boiler.

Chris you did install the baffle plate right it hangs on the inside brackets at top of boiler
when running a vac while cleaning the tubs from bottom you don't get any fly in your face
also clean the smoke shelve behind the baffle plate first use a vac or bush to push fly ash down thur the tubs
to bottom of base before taking off flue pipe. You go thur the round door to get to baffle plate /smoke shelve
some of the boilers had clean out door on the back of boiler that you could go thur there to clean out shelve
and tubes

Yup, I got the baffle plate hanging on the hooks up in there.

I came up with a clever trick to clean the tubes - I used a 1-1/2" diameter, 4" long nylon bristle brush with a flexible 36" twisted wire handle. I cut the little loop of the end of the handle and bent the brush portion into sort of a flat C shape. I chucked the end of the handle into my old cordless drill and stuck it up in each tube with the drill running. By running the drill in each direction, the brush would get both ends of the rectangular tube.

I think I'm going to keep the 5 gpm coil and get it clean out and pressure test it.
Now, I have 3 kids here, and no one take normal shower, I wonder if it a good idea to pipe from coil to electric hot water heater and have the pump circulating hot water all the time, just so we dont run out of hot water.
What you guys think?
Thank, Gerard

I had the same situation........never ran out of hot water

I wonder if it a good idea to pipe from coil to electric hot water heater and have the pump circulating hot water all the time

Don't need to, the coil should supply all the hot water you need.

cool, thank you

Wood'nCoal wrote:

I wonder if it a good idea to pipe from coil to electric hot water heater and have the pump circulating hot water all the time

Don't need to, the coil should supply all the hot water you need.

Ok, run a pressure test on the DHW coil--FAILED!
2 holes, fin wasent bend at at where the holes are
I dont think it worth repairing
What you guys think?

Most likely, no. If it was only those two holes, you might try it, but if more develop once it's installed, you'll have to drain the boiler and change everything. It's a gamble.

that gamble I'm not playing, might as well buy a 7gpm coil

I was thinking about getting a indirect hotwater heater instead of bying a new DHW coil for the EFM, guess what? I'm buying a new DHW coil instead, man, they are NOT cheap at all, I buy 3 coil before I buy that.
Gerard

Think I buy 1 for now, lol

I was able to get a warranty indirect heater which only needed a little brazing. I like it because I can store a large quantity of heat for a day without reheating. They lose about 1/2 degree of stored heat per hour, compared to about 10 degrees with a boiler. They also can provide an endless supply of hot water when hooked with a fired boiler. If it wasn't free, I'd stick with my coil.

If you are looking for a cheap indirect hot water heater look a my previous post.

Coal Fired Hot Water Heater

You might be able to get one for free. I got two free.

Worm bushing
which way do I get the old one out and the new one in?
Thank, Gerard