Baffled by baffles....

jpf321

According to my Fitzgibbons 400 boiler spec plate: <a href="http://picasaweb.google.com/jpf321/Fitzgibbons400Boiler#5407071581894736162">http://picasaweb.google.com/jpf321/Fitzgibbons400Boiler#5407071581894736162</a>



The boiler is supposed to use "baffles" if "mechanically fired". Well I would assume that a Beckett Oil Burner would constitute "mechanically" fired .. but what are baffles?



Does anyone have any Fitzgibbons 400 printed material? Or can someone explain what baffles are? Where they go? etc.



I have searched the web in earnest, but I fear that the Fitzgibbons 400 I & O manuals are now amongst the rarest of archived materials.



Thanks

nicholas bonham-carter

baffled by turbulators

here are a couple of links to the suggested baffle:

[url=http://www.nrel.gov/docs/fy04osti/33471.pdf]http://www.nrel.gov/docs/fy04osti/33471.pdf

[url=http://turbulators.com/]http://turbulators.com/

nbc

Unknown

Baffles.

Baffles are used in boilers to control the flow of heat. They usually have the purpose of directing heat evenly to the boiler surfaces (tubes,crown plate) that produce steam. They can also be used to control the velocity of the heat, usually to slow it down so there is more time for heat transfer.  This is the definition of baffles I learned and is for the type used in big naval boilers. I imagine it applies the same way to residential boilers. In the case of your boiler, which was originally probably coal fired, I imagine with the coal fire, wouldn't be necessary to have baffles as the coal bed would be distributed evenly across the bottom of the firebox providing even heat to the bottom of the boiler. With a gas or oil burner the heat source, being more concentrated, would need to be distributed, hence the need for baffles.

I haven't had that much experience with the use of baffles in residential boilers. I know the Burnham Megasteam uses them in the galleries to direct the heat to the surfaces of the boiler and to slow down the velocity for better heat transfer.

- Rod

Steamhead

Take a look at this

from the 1947 ASHVE Guide. This cut-away view of the 400 shows the spiral baffles (a.k.a. turbulators) that are installed in the tubes. Without these, the heat goes straight up the chimney.

Charlie from wmass

Frank I had to laugh.

Last year I put one of those boilers in the rolloff for the scrappy. We had it by the shop as a possible wood boiler for years. It is great seeing the photo of the old beast. Yep it had those turbulators in about half the tubes.

jpf321

truly amazing...

Steamhead -- your ability to come up with that obscure reference is truly amazing. Thanks. Let me know if you have any other paperwork for this beast up your sleeve...



on a slightly different note, the ad says that it's available in 320-900sq ft of steam .. any way to tell what size I have based on the spec plate? can we reverse calculate from the 165K BTU? when I divide 165,000 by 240 btu i get about 687 (sq ft?).



thanks again.

jpf321

another view...

Thanks to Steamhead leading the path .. I found another cut-away view in the 1950 ASHVE Guide.

[url=http://www.screencast.com/users/JPF321/folders/Jing/media/d7edd530-5260-4155-a68d-3723df3bcaca]http://www.screencast.com/users/JPF321/folders/Jing/media/d7edd530-5260-4155-a68d-3723df3bcaca

Steamhead

You're close

the spec plate shows you have the #402. The Hydronic Rating Handbook shows that boiler is rated 700 square feet steam (168,000 BTUH net) or 1120 square feet for hot-water (also 168,000 BTUH net). Firing rate with the then-current non-flame-retention oil burner was 2.3 GPH. With a modern burner like your Beckett, you'd only need about 1.8 GPH for the same effective heat input. Going by today's preference for raising pump pressures, a 1.50 GPH nozzle at 140 PSI would pretty much nail that.



I seem to remember that Fitzgibbons advertised their boilers as being suitable for use with any good oil burner. Given the variety of burners available then, this must have made for some interesting boiler-burner combinations.

jpf321

wow .. and the knowledge keeps on flowing...

I have only

371 EDR load (rads only) on the boiler +

120ft of 2in mains +

3risers running to 3rd flr @ 1-1/4in and +

2risers to 2nd flr @ 1-1/4in.



I have 1.75GPH 60deg SemiSolid Nozzle (was noted on my service tag) on my Beckett "SR" Series Gun. Can I drop my GPH substantially to support the 371 load? I guess the proper question is, am I overfired?



Other burner parts:



Primary Controller: R7184A-1075 Honeywell



Pump: Suntec A1VA-7112



Igniter: 746001

Steamhead

It's oversized all right

and I don't think you could down-fire enough it to match your radiation without causing the stack temp to get too low, very slow response, or both.  You might be able to get away with a slight reduction, say 1.5 GPH or so, if it doesn't take the stack temp below about 350 with baffles in place, and the boiler doesn't take a long time to make steam.



Maybe it's time for a new boiler that's properly sized.

jpf321

it's on my wishlist...

i had 2 different guys come in already for quotes for new boiler .. both were knuckleheads... but it's NYC so I expect nothing less.



one was from the GAS company ... and he simply looked at the spec plate and told me I need a 165K btu.. $6000 flat for job...no options, no discussions...flat price.



the other was from the OIL company .. at least he counted (not measured) the number of rads in the house ... he refused to email me a quote and instead called me and expected me to follow and take copious phone notes .. not my preference



i don't really trust buying consumption equipment from the fuel provider .. maybe it's just me. i did find out that my neighbor put in a peerless steamer some time ago and they are now undergoing a oil -> gas conversion .. maybe I can ask their guy to stop over.



either way, no moolah currently for any new steamware.



for the record, i'm not sure that I have proper baffles in .. I think I just have flat pieces of metal in the tubes .. but they aren't spiralled or anything .. just flat and straight .. when the boiler cools down a bit, i'll see if I can get some pics.



just a final question .. why is "350" the magic temp for stacks? it that what is needed to ensure upward draft?