Series 3 Firetube Boiler

Series 3 Firetube Boiler

The Burnham Commercial Wetback Packaged Boiler can save you thousands of dollars over the life of your boiler. Our quality engineering takes maximum advantage of long-term energy and maintenance efficiencies. Unless you take those efficiencies into consideration along with price when you choose a boiler, you can be in for enormous hidden costs.The Series 3 matches burner to boiler, providing a fuel efficient low-maintenance package. It takes maximum advantage of long-term energy and maintenance efficiencies.

Design Firetube
Heat Exchanger 3 Pass
Standard Design Pressure Steam: 15 psi/150 psi
Standard Design Pressure Water: 30 psi/125 psi
Burner Customer Preference
Fuel Gas/Oil/Propane
Venting Forced Draft
Heating Surface- Sq Ft 5.0
Low Pressure Water Coil Yes
DOE/AHRI Status Certified


  • Low or High Pressure Steam or Water
  • Highly Efficient Three-Pass Design
  • Fully Waterbacked Primary Heating Surfaces
  • Separate Rear Tube Sheets for Longer Service Life
  • Wetback Design Allows Easy Front and Rear Access
  • Made in the USA
  • No Expensive Refractory or Door Replacement as with Some Drybacks


  • Forced-Draft Firing with Oil (No. 2,4,5, or 6), Gas, or Combination Gas/Oil
  • Low or High Pressure Steam or Water
  • High Efficiency Three-Pass Design
  • Fully Water-Backed Primary Heating Surfaces for Increased Efficiency
  • Separate Rear-Tube Sheets for Longer Service Life
  • Easy Front and Rear Access for Ease of Maintenance
  • ASME Code Construction

Boiler Cost is Not Just a First-Year Proposition.

Long after the installation is paid for, fuel, maintenance, and repair costs continue and can increase over the years. Burnham Commercial Packaged Boilers are designed to minimize these significant, ongoing ownership costs.

That’s Burnham Commercial’s High Life-Cycle Efficiency!
While most competitive boilers can give fuel-to-steam efficiencies of 80% or over when they are new — how consistently can they be expected to maintain this level? Burnham Commercial wetback boiler performance will not drop due to deteriorating rear refractory, leaking door baffles and seals, and heat-stressed rear tube sheet as can happen with some drybacks: the fact is that easy access is a necessity for those with heavy refractory, as they need frequent, expert maintenance.

The Burnham Commercial Wetback Saves Money on Maintenance.
Over the life of a dryback, brittle refractory baffling and rear door gasketing will require continual monitoring, maintenance, and replacement, costing thousands upon thousands of dollars. These built-in maintenance coats can eventually equal or exceed the original cost of the boiler as refractory deteriorates, leaking hot gas causes boiler efficiency to fall until the condition is noticed and repairs can be made (expensive flue temperature alarms are offered with some drybacks to monitor this dangerous and costly potentiality). The rear door itself can become heat-distorted, requiring an expensive replacement. In addition, boiler downtime during repairs can mean crippling losses.

This waste of time and money is eliminated with the Burnham Commercial Wetback: as it has an actively functional water jacket, there is no need for a refractory wall, rear door, rear door inspection and sealing, door swing space in the boiler room, or flue temperature alarm. These costly maintenance headaches are gone, while boiler performance is increased. Burnham Commercial has only a small, inexpensive refractory area in the rear access port. The furnace and rear turn around area are cool running, fully wetbacked radiant heat transfer surfaces. They promote good internal water circulation and rapid heat absorption. There is no need for the forced internal circulation pumps often specified to cool the rear tube-sheets in drybacks.

The Burnham Commercial Wetback is Built to Last.
Typical dryback boilers have a common rear tubesheet which expands and contracts at different rates adjacent to each tube pass, stressing tube ends and increasing the likelihood of leaks. Compounding this problem, the heavy refractory used in some drybacks reflects intense heat to the rear tube ends and tube sheet, accelerating their deterioration. Sometimes, welding of the rear ends of tubes has been done in attempts to stop leaking. Cleaning or tube replacement involves opening both the front and rear covers and resealing them when the job is done. Usually, if tubes have been welded at the ends, the welds must be burned out, the tube sheet repaired (or a new segment welded in) and the new tubes welded also.

These damages and expenses cannot be incurred with the Burnham Commercial Scotch Marine; separate rear tube sheets free each pass to expand and contract at its own rate without tube-to-sheet stress. Tubes are rolled and flared in low pressure units; and rolled, flared and beaded in the high pressure ones. No welding of tubes is permitted, nor is it necessary. Any eventual tube replacement is a mechanical, not a welding, operation: uncomplicated and less costly.

It All Adds up to Significant Cost Performance Advantage.
These energy and maintenance features add up to real savings for you. Our design for long-term efficiency and economy of operation makes Burnham Commercial Packaged Wetback Firetube your cost-performance leader!

Burnham Commercial Scotch Marine Boilers match burner to boiler, providing a fuel-efficient, low-maintenance package. Maintenance costs can be further controlled in your boiler room with optional accessories. Such options include state-of-the-art annunciator systems, custom designed to monitor all boiler and burner interlocks vital to your particular installation. They provide instant readout of both normal and abnormal operating conditions, pinpointing any causes for unscheduled shutdowns, and reducing maintenance time and skill required.


  1. Three Gas Passes Extract Maximum Usable Heat From the Fuel While Maintaining Optimum Flow for Forced Draft Firing.
  2. Fully Waterbacked Reversing Chamber Effectively Absorbs Radiant Heat Into the Water Keeping Tube Ends and Rear of Boiler Cooler Than Those of Hot·Running Dry backs
  3. Large Fully Waterbacked Furnace Tube Assures Complete Combustion and Heat Absorption Without Flame Impingement

Front view
Ready access to tubes through rugged front doors and rear covers makes routine cleaning easier and less costly than with dry backs. The burner does not have to be disturbed. There is n o inner air baffle door to contend with. There are no delicate, expensive baffle tiles or door seals to replace.

Rear view
After the doors have been opened on the Burnham Commercial wetback boiler, there are no specialized skills or expensive repair materials needed to reclose them as with dry backs. Simply tightening the closure bolts reseals the doors. Cleaning can be done inexpensively and the boiler put back on line quickly by your in–house personnel.



Three-pass firetube type, constructed with heavy steel, in accordance with requirements of the ASME Code. All units are registered with the The National Board of Boiler and Pressure Ves­sels.

Water cooled sidewalls in the rear turnaround promote rapid internal circulation and reduce gas temperatures at the entrance to the second pass, reducing tube end stress. All tube ends are rolled and flared.

Easy-opening insulated front and rear flue doors with light weight non-refractory closure pro­ vide full access to all tubes. No elaborate seals are used. The C Series oversized furnace easily accommodates any burner.

Washouts are provided for easy inspection and cleaning of waterside surfaces. All steam boil­ers are provided with a dry pan to ensure dry steam. A feedwater diffuser is provided on steam boilers. All water boilers are equipped with a dip tube at supply outlet and diffuser at return inlet.

The round vertical smoke outlet has room for an optional quadrant damper. All boilers are pro­vided with lifting holes and an enameled steel jacket installed over fiberglass insulation. The boiler is mounted on a heavy-duty structural steel base with extended skid and burner platform for protection of the burner during shipment and rigging.

Standard Trim and Controls:
Steam: 157 pump control/low water cut-off with alarm contacts-piped with quick opening blowoff valve. Gauge glass set with hand-operated gauge and try cocks. Steam pressure gauge- 4-1/2″ dial. L404F operating pressuretrol, L4079B manual reset high limit pressuretrol and appropriate firing rate control when required. Manual reset probe auxiliary low water cut­ off. ASME side outlet safety valve(s).

Water: 750-MT manual reset low water cut-off-piped with quick opening blowoff valve. Com­bination pressure/temperature gauge- 3-1/2″ dial. L4006A operating aquastat and L4006E manual reset high limit aquastat and appropriate firing rate control when required.

ASME side outlet relief valve(s).