Reference Photos for Mills 4500 A

Smith19

Does anyone have any decent reference photos of HB Smith Mills 450/45000 A boilers that show a good flue breaching detail? Helping a client develop a 3D BIM library for out-of-production boilers and am noticing that there is virtually no technical information about the Mills boilers online. Whatever company bought HB Smith has the specs for the 4500 A posted, but the graphics are totally illegible and are relatively light on flue details.

Client also wants to have an option of the boiler modeled with a circular flue in addition to the standard square breaching - was this ever an option?

EBEBRATT-Ed

I threw all my old Smith stuff away. The 350/450/650 are all gone. They all used a rectangular breeching to tie the two back sides together. To connect that header to the flue you can use rectangular or round. It has to be large enough because those boilers all have to be operated with a neg draft in the fire box.

413-562-9631 Call Smith

Smith19

https://forum.heatinghelp.com/discussion/comment/1904386#Comment_1904386

What exactly happened to HB Smith? When did they get rid of the Mills products?

EBEBRATT-Ed

Yes. Smith only sells 2 boilers now. The model #19 and the #28…..if that. All the Mills boilers are gone …sad. And they made millions of them.

AJCimino

Hope this helps

1.HB Smith 450 Mills Catalouge 2628-A.pdf

2.HB Smith Mills 350.pdf

4.Mills 45 Combustion Chamber Assembly Catalogue 2730-A.pdf

3.HB Smith Mills 450 Catalouge .pdf

5.Mills 450 Jacket Assemblypdf.pdf

6.Mills 450L Catalouge 2736B.pdf

HeatingHelp.com

@AJCimino, thanks so much for taking the time to scan these documents and for sharing them with us. They are fantastic. We've posted them in our Heating Museum here:

https://heatinghelp.com/systems-help-center/category/heating-museum/

EBEBRATT-Ed

😊😊😊😊

retiredguy

I helped and instructed many contractors on how to build thousands of the 350/3500, 450/4500, and the 650/6500 H B Smith boilers. They were not the most efficient boiler design but if you wanted longevity these were the boilers that you wanted. You could replace any bad section without having to disassemble the whole boiler. For many years, they were the companies "bread and butter".

EBEBRATT-Ed

@retiredguy

With Smith located in Westfield, MA about 10 miles from me back in the 70s when I started it was rare to see any other CI boiler in my area that was not a Smith. almost every school in this area had Smith boiler they had this area locked up pretty tight.

They were pretty efficient when new. But when the insulating cement between the sections broke down over time they leaked in a lot of x cess air that reduced efficiency

Smith19

https://forum.heatinghelp.com/discussion/comment/1904846#Comment_1904846

Thank you! Very helpful.

Smith19

https://forum.heatinghelp.com/discussion/comment/1905222#Comment_1905222

Did these typically come with a power flame burner as standard spec?

EdTheHeaterMan

@Smith19 asked: "Did these typically come with a power flame burner as standard spec?"

I believe when the first Smith-Mills boilers were originally designed, the factory burner package consisted of a shovel and a fireman.

The fuel was manually introduced into the combustion chamber by placing coal on the grates with the shovel. The firing control was completely mechanical, although it did require a fairly sophisticated human interface.

Modulation was accomplished by adding more or less coal, and combustion testing usually involved looking at the fire and deciding whether it looked about right.

If you ever have trouble finding the original burner assembly, replacement shovels are still readily available at most hardware stores, farm-supply stores, and probably a few general stores.

It was an extremely common firing configuration. The biggest disadvantage was that the burner technician occasionally demanded lunch breaks and a paycheck.

As the years went by, some of those Mills boilers did have PowerFlame burners installed, I remember removing a Mills Boiler from a Church that was fired with a Carlin Oil burner.

EBEBRATT-Ed

@Smith19

Smith started using Power Flame gas or #2 oil or gas/oil burners back around the early 60s AFAIK. But they also used Carlin oil burners on oil in the old days.

Heavy oil they usually used Preferred Utilities burners

As time went on (and depending on the size of the boiler and the fuel) you would find Power Flame, Preferred, Industrial Combustion, Carlin, Webster and maybe some others.

But I would guess a very high percentage of their factory packages (boiler sold with burner) were Power Flame