Burner insertion depth-Smith BB14

Saggs

I'm working on a Smith BB14 steam boiler and have put a new chamber and other gaskets on it. Carlin 100crd Blast tube presently extends 2" past the insulation block on the front panel and is unprotected. The blast tube is cracked and peeling back from the heat. Question is, burner looks to have welded factory mount. Is there a missing insulation boot for the end of the blast tube or should I get an adj. flange and set it just back of the insulation when I install the new blast tube? Thx

Dick Charland

Not sure what dimension the insulation block is that you currently have. Originally, there was a large donut like block (round opening) that protected that area. Memory fails me as to exact dimension possibly 5" or so. If that is original burner, that would account for discrepancy.

Saggs

The orig "donut" insulating block is still in the front plate. It's probably 3" thick. The blast tube is protruding another 2" beyond that hanging out in the breeze. It should be protected from the heat by somthing. Maybe new tube and adj flage, pulling the burner back 2"?

Guy_6

BB14

There are "head" protectors available that would cover the end of the blast tube, but the consensus of us younger (ahem) Smith guts is to use an adjustable depth flange and set the end of the tube flush with the face of the insulation donut. If you would like more help, please call me at 508-930-6448 and I will do whatever I can.

I have a wholesaler in Dorchester MA that has 2 or 3 BB14 blocks, never used, that are collecting dust if anyone is looking for such a relic.

Guy Woollard
Smith Boiler Co.

John@Reliable_12

From Beckett....................

book 2 1/4" INSERTION DEPTH for all sizes, checked Carlin book maybe same depending on how many sections boiler has.
check out carlincombustion.com for your size.

Guy_6

more

One of our younger (OK, he's about MY age) tech people found out that the donut insulation block in the boiler is TWO FACED: The CONCAVE side toward the chamber is for a Beckett, and reversed-FLAT side toward the chamber is for Carlin. The difference is that 2 inches that are in question.
Why different tube lengths, I don't know.

Weezbo

Saggs, here are a couple ideas to consider

one is that insulator doughnut another is the insertion depth the other is the cooling effect of an air passage way around the front of the assembly and another is the nozzle spray pattern. each one of them changes where the combustion is taking place. end cones interior insulation fire chamber depth size configuration...combustion make up air requirements all need to be "Right" before you test ,basically.

getting the boiler manufacturers spec sheet and the burner manufacturers spec sheet for that boiler is a great place to Start.

some small fractions of an inch throw things way out.

sometimes the make up air needs to be investigated a bit more thoroughly than seeing a hole in the wall ....if there are vehicles idling outside in the makeup air as a regular course of events i know for a fact that it can cause problems with the burner. any exhaust fans or air cooled motors can monkey with things also. you sound like you are savey on this so it occurs to me that when you saw the end of the gun 2 " into the combustion chamber beyond the insulator you reckoned it to be "Different". the bigger the fuel consumption of the appliance the more critical minor technicalities become. Blam ! is not good. get the spec sheets and start from there. sometimes there may be something gone from the picture and that may cause some discrepancies also. a gasket might not seem like much around the face plate (burner mountingbracket) however it is a fraction ....on dry base there are things you might not see properly without removing the skins...

to me it sounds like it has some air problem as in not enough and that while it may be the burner has functioned for years that way it might need to be measured exactly how deep you need to keep the end of the burner. for the most part these have a setting like 2 1/2 " or measuring from the other direction back a 1/4... let me also say that oil heat cares *~/:) try Alan 's site if you dont find info on the burner and boiler easily...i think he has a section where you can round up the info easily.

Dick Charland

Sounds like you may have answered the question, in all the years I've done it, I never heard of the reversible donut. Of course, all of the BB14's I worked on had Carlin burners at the time. If this is the original install and the air tube is still intact then that is amazing. I just checked my Carlin reference and the insertion depth is 4 3/8".