Industrial Firetube Boilers, 5 to 800 Horsepower
Dryback and wetback Scotch marine boilers for steam and hot water, built to ASME Section I or Section IV in our California code shop. Standard sizes, or custom-designed to your load and boiler room.
Code-built boilers and vessels
Code repairs and alterations
Factory-authorized Tech Center
Factory-authorized Burner Tech Center
Fifth generation, family-owned
QUICK ANSWER
McKenna Boiler Works, Inc. is a firetube boiler manufacturer in Oceanside, California, building Scotch marine boilers from 5 to 800 HP. They are stamped to ASME Section I or IV for steam at 15, 150, or 250 psig and hot water at 125 psig. Wetback designs start at 100 HP. Low NOx and ultra-low NOx designs reach as low as 2.5 ppm NOx (corrected to 3% O2) on select models. For boilers of 2,000,000 Btu/hr or less, McKenna has units pre-certified to South Coast AQMD Rule 1146.2. Call (323) 987-1816.
At a glance
Firetube boiler specifications.
Every McKenna firetube boiler is built to order. These are the ranges we build to; your proposal lists the exact rating, dimensions, and trim.
Type
Scotch marine firetube
Designs
Two-pass dryback, two-pass wetback, three-pass wetback
Size range
5 to 800 HP dryback; 100 to 800 HP wetback
Design pressures
Steam: 15, 150, and 250 psig. Hot water: 125 psig
Media
Steam or hot water
Code
ASME Section I (S stamp) or Section IV (H stamp)
Burner and controls
A burner matched to the boiler and the emissions limit, with Autoflame controls as a standard option. Prefer a specific burner? McKenna also installs and tunes burners and controls from other manufacturers, including a brand your engineer specified
Fuels
Natural gas or propane. No. 2 oil as a backup fuel, or dual fuel. Hydrogen and hydrogen blends with a burner rated for them
Burner package
Piped, wired, and tested in our shop before the boiler ships
Service access
Full access to the tubes, tubesheet, and furnace. Standard, off-the-shelf replacement parts, not proprietary ones
Built
Standard sizes or custom to your spec and room
NOx
Low NOx and ultra-low NOx, as low as 2.5 ppm NOx (corrected to 3% O2) on select models
2,000,000 Btu/hr or less
Units pre-certified to South Coast AQMD Rule 1146.2
Sizing
Not sure which size you need?
Send us the steam or hot water load, the pressure, and the room. A McKenna engineer will size the boiler and get back to you.
Three designs
Dryback or wetback.
Not sure which fits your plant? A McKenna engineer will tell you plainly, based on your load, hours of operation, and maintenance crew.
Two-pass dryback
5 to 800 HP
- Combustion gases turn in a refractory-lined rear chamber.
- The rear door opens for full access to the tubesheet and refractory.
- Covers the widest size range, from small heating plants to process steam.
Two-pass wetback
100 to 800 HP
- The rear turnaround chamber is surrounded by water, so there is less refractory to maintain.
- Gases make two passes, through the furnace and then the tubes, before the stack.
- A wetback option across the mid and large size range.
