cracked refractory etc.

TomM · February 2010

3 questions- see attached pics

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I noticed that the refractory is cracking in my 1989 Crown steamer. At what point does this become a problem? when its totally broken? A new one for this boiler is no longer available from the manufacturer.

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also, you can see the flame from the access door when the door is totally shut. see attached pics. shouldn't this be sealed b/c it adds to too much air? or is this leak probably already accounted for in the burner air setting.

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3rd question- How is it possible to inspect the flame shape? whenever the inspection door is opened, it introduces excess air into the system and the flame gets larger. Is that how flame shapes are inspected in the field?

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Thanks! TomM

Steamhead · February 2010

That should be replaced soon

if Crown no longer sells them, a chamber company like Lynn Products probably does, or else a standard "bathtub" chamber might fit. Of course you'll want to have a pro install it, and clean it out while he has everything apart. Looks like it needs to be cleaned anyway. Then the burner will need to be re-tuned. Consider upgrading to an electronic primary control and a CleanCut pump on that burner, this will result in much cleaner starts and stops, with less sooting. Ask me how I know that.

On this type of boiler, as long as the draft is not excessive, that observation door should not leak much air into the chamber.

The flame shape is determined by the nozzle size and spray pattern and the burner design. By 1989, boiler makers had this pretty well nailed down. Following the OEM specs is your best bet, though there are exceptions. You should get a pretty good idea of what the flame looks like the instant you open the door. The flame should not contact the refractory except for a lick here and there.

A true pro will adjust the burner with a digital combustion analyzer. Anyone who doesn't use one of these cannot set a burner up properly. Period.

What exact model is your boiler?

fud215 · February 2010

answer

if that is a wet based boiler you don t need a chamber you can fire the boiler with out a chamber. you just need refactory on the burner mounting plate. if you don t feel comfortable with out a chamber you can use a wet pack and line the target wall and inner sides of the boiler remove old chamber first. done this many times both ways. never cracked a boiler.

also i have adjusted fire without an analyzer, using a flash lite and draft regulator. you can adjust a fire by smell and by looking at the fire have done it for years. i have an analyzer and when i have a lot of no heat calls i do it this way. i have been doing it this way for 20 yrs residental and commercial.

Steamhead · February 2010

Well, I hope

you have a good lawyer- not using an analyzer every time you adjust a burner is asking for trouble. It really doesn't take that long to use one, and besides, a callback takes much more time. Why take the chance?

If a wet-base boiler was not designed for chamberless firing, doing so can reduce the flame temperature to the point where it creates soot. You need a good flame environment for clean, efficient combustion. Again, why ask for trouble?

Paul Fredricks_3 · February 2010

But Frank...

We've always done it that way

Steamhead · February 2010

And

Grandpa never needed an analyzer...... :-0

That's "Grandpa", not "GrandPAH"! I don't think our friend Dave ever leaves the shop without an analyzer.

Charlie from wmass · February 2010

Those there analyzers are for

those who don't have a good eye. You can tell by the sound if its tuned right. the same with the pressure on the pump. And the best way to size a boiler is the thumb method. one thumb per section from across the street.

Sigh, Frank I thought that by now these types would have died off due to on the job injuries or CO poisoning. They seem to multiply every day.

I have a boiler I have been working on the back section is cracked and the installer says this boiler does not use refractory. Funny thing is the first step in the manual is to install the refractory before assembling the block. The install went quite when showed this and gave me their address to mail the bill to for the repairs .

Steamhead · February 2010

Here's the cycle

Knucklehead has been working in the heating business for X number of years, probably bouncing around several different companies.

One day his current employer decides he needs another employee, so he hires a kid fresh out of school, because he still lives with his parents and will work cheaply. We'll call him Emptyhead. The boss sends Emptyhead out to work with Knucklehead, and pretty soon Emptyhead has learned how to be Knucklehead 2.0 . This, he figures, is all he needs to keep himself employed. His bosses won't want to spend any money on actual training.

Knucklehead will probably do this quite a few times in his career.

Years later, Knucklehead 2.0 is told to break in the latest Emptyhead to come along. So the cycle repeats itself.

What kind of boiler was that?

TomM · February 2010

called lynn

I called Lynn Products, aka Lynn Manufacturing in MA, and they were very helpful, but a direct replacement doesn't exist. I'd have to fit a 12"x11 3/4" x 10 3/4" bathtub style refractory.

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oh yeah, its a 1989 Crown DS405 steam boiler. tjerlund SS1 powervent, all completely rigged to the max. Funny, the powervent is sloped upwards out the wall, so it rains into the powervent. cool, huh?

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I was wondering about the excess draft because mine is reading -.03 -.04 at the burner. Seems high. Actually, now that I think about it, a breach at the burner would yield a lower draft, right?

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Steamhead + others, you don't recommend the old school Fyrite kits? only digital combustion analyzers?

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Steamhead · February 2010

The old wet kits

don't measure carbon monoxide. Digital ones do. Enough said.

Draft is typically a bit higher at the breech than over the fire, but there are exceptions. -.03 at the breech should be OK on that boiler, but the same amount over the fire would be a bit much- unless the manufacturer calls for something else.

Might also call Crown Boiler to see if they still stock that chamber. I ran into this on a Smith BB-14 boiler, Lynn didn't sell the proper chamber but Smith did. I got the part number and the rest was history.

RAF · February 2010

Any tester is better than no tester

Say by the look of your inspection door ( looks burnt) Is your proving switch working?

TomM · February 2010

proving switch?

by 'proving switch' do you mean cad cell light detector?

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From beckett website:

To understand how to troubleshoot the cad cell, it is important to first know how the control operates. Initially, the control must have a high resistance across its F-F terminals (cad cell does not sense visible light) before it will attempt to start the burner. If the cad cell senses light or is shorted, the relay in the primary control will not pull in to start the burner. Once the burner is running and the flame is established, the cad cell must have a low resistance (cad cell sensing flame) to keep the primary control from locking out on safety.

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Wouldn't the burner not work at all if the proving switch was even slightly not working correctly?

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Also, Crown does not have any parts for my boiler available whatsoever, including a new refractory.

Coany · February 2010

pretty harsh

I have learned all sorts of little tricks from more experienced techs

not all of them strictly by the book

some, in an emergency, have proven to be very helpful.

I agree that taking a combustion test every time you adjust the fire is wise.

what kind of tool you use to do it is secondary.

digital is expensive to buy

most don't get them professionally checked for accuracy nearly often enough.

or ever. The excess air reading is extremely helpful I'll admit.

the fyrite kit is nice and simple, I can maintain it myself to assure accuracy.

which you cannot do with digital ones.

RAF · February 2010

oops my mistake

I thought you said you were inducing the draft my mistake. A Lynn chamber should work fine in your unit.

Steamhead · February 2010

"digital is expensive to buy"

Well, they're not cheap, and like anything else they do need to be maintained, but you can get the job done faster with a digital analyzer. Have you timed how long it takes to pump and shake that old Fyrite each time you adjust something? With digital you can see the change right on the screen in several seconds.

And to test a gas-fired appliance, you need to either change the fluid in that martini-shaker (which takes time) or maintain a second complete kit for gas (which brings the total cost fairly close to that of a digital unit). And it still won't test for CO, which is one of our industry's most serious issues these days.

Oh, and many of our customers are impressed when they watch us tune their boilers on the analyzer. These units have a distinct "cool factor".

When I got my first Testo, I was so impressed with how much it improved my work that I bade the wet-kit goodbye. Digital is the way to go.

Paul Fredricks_3 · February 2010

Ditto

And to add to Franks comments I'd like to point out that testing after adjusting the flame is not only a good idea, I believe it is required by NFPA. Our techs are told to efficiency test any time they do anything that effects combustion, like changing and air setting, pump pressure or changing a nozzle.

billtwocase · March 2010

chamber

Yes that boiler needs one. It's an old design-Texaco/Paragon boiler. I've done alot of those chambers. Quikie 100, and get an "A" wetpack kit to use as a shim between the chamber and front plate, as those bathtubs will walk forward, causing the blast tube/endcone to be inside the chamber thus burning off real soon. Also the taller of the chamber ends should be your target wall, and if you cut the material, use waterglass. good luck

cracked refractory etc.

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