Hurst Boiler - Low NOx Boilers

The Hurst 400 Series three-pass wetback scotch marine boiler is an ideal choice for all commercial and industrial applications when engineering mechanical systems using the latest HVACR technologies. The Hurst 400 Series boiler provides fuel efficiencies that exceed most four-pass designs. Having no large refractory rear door, these boilers allow one technician easy access to all tubes. The boiler’s front doors can be opened without removing any burner components or controls.

Capacities range from 15 to 2,000 HP and 1,004 to 50,213 MBTU/HR. Available for 15 PSI Steam and 30 PSI Water (60 PSI Water Optional).

• Factory assembled, prewired and tested
• No field assembly required
• UL listed boiler/burner packages
• Fully assembled, prepiped, prewired, pressure tested gas trains
• Complies with ASME, UL, CSD-1 and ASHRAE standards
• High efficiency, low stack temperatures
• Customer service support through national network of sales, service, start-up, training and parts by factory representatives.

Wetback Advantage

Dry backs boilers are subject to deteriorating rear refractory, leaking baffles, leaking door seals, and often found with a heat-stressed rear tube sheet. Fragile refractory baffling and door seals will require continuous monitoring, maintenance, and replacement, costing thousands of dollars in materials and specialized labor costs over the life of the boiler. In addition, broken baffles and leaking seals will short-circuit the boiler’s gas flow, causing high stack temperatures and lowering efficiency until repairs can be made.

Standard Features

Durability
Built in accordance with the ASME Code, the wet back design has proven to give much longer useful life cycles than dry back boilers.

Quality
Each unit is tested and inspected and registered with the National Board of Boiler and Pressure Vessel Inspectors.

Design
Hurst Boiler utilizes state of the art computer design techniques in every boiler. This accounts for accurate calculations of construction materials and optimum utilization of the boiler’s performance criteria.

Efficiency
The Series 400 boiler is designed for optimum fuel efficiency and has proven in certified tests to meet, and often exceed, the efficiencies of four-pass boilers.

Low Maintenance
There are no refractory baffles to replace or maintain. Elimination of these will result in thousands of dollars in savings.

Tube Sheets
The wet back has independent tube sheets with uniform temperatures. Three and four pass dry back boilers have tube sheets with large temperature variations and this results in premature tube failure and cracks in the tube sheets.

Easy Access
Since there is no large refractory rear door, one man can easily remove the rear cover plates for access to the tubes. Front doors can be opened without removing burner components or controls.

Compact
With computer aided design, Hurst has made the wet back a space saving workhorse without sacrificing the principle of 5 sq. ft. of heating surface per BHP.

Combustion
Hurst uses name brand burner components with proven reliability. Every unit is boiler/burner compatible and tested at the factory prior to shipment.

Available in Steam or Hot Water Versions 15 – 800 Bhp Pressures to 300 psig

• Three-pass design
• 81% minimum efficiency
• Davited rear doors
• Low maintenance
• 5 sq. ft. heating surface/HP
• Durable design
• Heavily constructed

Standard Features

• Boiler is of three pass dry back, scotch type, built and stamped in accordance with the requirements of the ASME Code, and listed by the National Board of Boilers and Pressure Vessel Inspectors.
• Large combustion chamber with low heat release for complete combustion.
• Rear smoke box includes slip-on stack connector and features hinged and davited rear door (all sizes) with 16″ dia. access door with 2″ observation port (80 Hp & larger).
• Front doors are hinged, bolted and insulated (80 Hp & larger) to provide ready access to all firetubes.
• Large 12″ x 16″ manholes are standard on larger units (40 Hp & up). Cleanout hand holes 3″ x 4″ are furnished in the bottom of the boiler shell.
• Insulated with 2″ high-density fiberglass, the shell is covered with 22 gauge grip jacketing and spray baked on powder coat finish.
• 2 1/2″ dia. steel firetubes (2″ dia. through 30 Hp) are rolled and beaded on power boilers, expanded and flared on low pressure boilers.
• Twin lifting lugs are securely welded to the top of the shell. Heavy steel support legs on skids provide support for the boiler & burner.

Capacities From 8.5 to 813 HP 285 to 27,215 MBTU/HR. 15 PSI Steam 30 PSI Water (60 PSI Water Optional)

• Efficient 3-Pass Design
• Flexibility – Gas, Oil, Heavy Oil, and Combination Gas/Oil
• ASME Code Constructed & Stamped for 15 PSI Steam/30 Water
• Registered with the National Board of Boiler Inspectors
• Competitively Priced, Easily Maintained, Designed for Efficiency
• Large Furnace Volume for Ultimate Combustion Efficiency
• Unified Refractory Base Floor
• Steel Skids and Lifting Eyes
• Low Heat Release – 5 Sq. Ft./HP.
• Factory Insulated – 2″ Mineral Wool
• Factory Jacketed & Painted
• Easy Access to Fireside Surfaces
• Ample Waterside Cleanout Openings
• Fully Automatic Operation
• UL Listed, Forced Draft Burners
• Wet Back Construction
• UL Listed Controls & Trim
• Factory Test Fired
• Flame Observation Ports Front & Rear

Standard Features

All units are factory packaged with operating controls, relief valves, burner and fuel train. Installation is made simple in that only service connections are needed to place in operation. Flexible burner systems are available for firing natural gas, LP gas, #2 oil, heavy oil, or combinations. High density 2″ mineral wool insulation assures lower radiant heat loss. In addition to meeting the requirements of UL, burner systems are optionally available to meet the requirements of FM, IRI, MILITARY and others.

Capacities From 8.5 to 813 HP 285 to 27,215 MBTU/HR. 15 PSI Steam 30 PSI Water (60 PSI Water Optional)

• Efficient 3-Pass Design
• Flexibility – Gas, Oil, Heavy Oil, and Combination Gas/Oil
• ASME Code Constructed & Stamped for 15 PSI Steam/30 Water
• Registered with the National Board of Boiler Inspectors
• Competitively Priced, Easily Maintained, Designed for Efficiency
• Large Furnace Volume for Ultimate Combustion Efficiency
• Unified Refractory Base Floor
• Steel Skids and Lifting Eyes
• Low Heat Release – 5 Sq. Ft./HP.
• Factory Insulated – 2″ Mineral Wool
• Factory Jacketed & Painted
• Easy Access to Fireside Surfaces
• Ample Waterside Cleanout Openings
• Fully Automatic Operation
• UL Listed, Forced Draft Burners
• Wet Back Construction
• UL Listed Controls & Trim
• Factory Test Fired
• Flame Observation Ports Front & Rear

Standard Features

All units are factory packaged with operating controls, relief valves, burner and fuel train. Installation is made simple in that only service connections are needed to place in operation. Flexible burner systems are available for firing natural gas, LP gas, #2 oil, heavy oil, or combinations. High density 2″ mineral wool insulation assures lower radiant heat loss. In addition to meeting the requirements of UL, burner systems are optionally available to meet the requirements of FM, IRI, MILITARY and others.

The compact, space saving vertical four-pass shock-proof design has no tubes to loosen or burn out. The Hurst Vertical Tubeless Boiler allows convenient access to “eye high” burner and solid-state controls for trouble free operation. Factory assembled and fully automatic. UL and ASME CSD-1 approved. Simple and inexpensive to install.

The compact, space saving vertical four-pass shock-proof design has no tubes to loosen or burn out. The Hurst Vertical Tubeless Boiler allows convenient access to “eye high” burner and solid-state controls for trouble free operation. Factory assembled and fully automatic. UL and ASME CSD-1 approved. Simple and inexpensive to install.

Inspection Access

• The waterside openings are located in the most effective positions. The lower handholes offer far better access for both cleanout and inspection.
• These more functional locations avoid the obstructing handhole “tunnels” used by our competitors.
• The top opening offers a strategic view of the furnace crown sheet.

More Steam Storage

• Capacity to handle swing and spike loads – quick recovery – quick response.
• The larger steam-release surface is calmer, reducing carry over of unevaporated water.
• The resulting drier steam also reduces system scaling.
• In addition, dry steam helps to eliminate unnecessary extra condensate. Energy and fuel are saved. Longer life results.

Four-Pass Design

• The gases leaving the furnace are split four ways and travel through four individual serpentine fin passages to the stack outlet.
• Each quarter of the heat travels its own four-pass path (see illustration below).
• Heat transfers evenly to the fins and boiler shell, eliminating the metal stress due to uneven heat transfer common in other designs.

This illustration shows the progression of four gas paths around the circumference of the boiler shell.

1. Primary-pass in furnace pipe.
2. Second-pass follows path through fins along outside of shell.
3. Third-pass follows path through fins along outside of shell.
4. Fourth-pass follows path through fins along outside of shell, then merges together to exit exhaust stack.

Options and Alternatives

• We specialize in customizing your boiler. The Cyclone can be equipped to suit a wide variety of installations and specifications. We will help direct you to the most cost-effective models and features.

Simple Installation

• Unit is skid mounted for easy handling.
• Factory wired with wiring schematic included in the manual. Efficient and space saving layout.

Available Accessories

• The Cyclone is available in a complete package with an optional compact boiler-mounted feedwater system for a finished wired and piped, ready-to-fire unit.
• Blowdown separators are also available.

Turbulent Flame

• Heat is forced down, with the fire whirling and spinning against its natural flow. This pattern enhances recirculation, mixing and heat transfer, driving more energy into the water for greater fuel-to-steam efficiency.

Reliability

• The furnace crown is water cooled, eliminating troublesome refractory breakdown inherent inunits of inferior design.
• No fire tubes, water coils or “in the fire” mud rings to burn out.

“Eye High” Burner

• No step ladder is needed to service.
• No bending over or sitting on the floor.
• The air intake is located in the center of the unit so dust is not pulled from the floor.

Durability

• Fire does not pass under the bottom mud ring, eliminating the blistering that occurs with other designs.
• Cooler furnace gases are located at the bottom of the vessel where scale is most likely to occur. Baking of scale is alleviated.

Easier Service

• Fireside fin access in top and bottom.
• Access opening above feedwater inlet for easy cleaning.
• Thoughtfully engineered with the owner in mind.
• No heavy doors or covers to complicate service procedures.

Safety

• Electrical components are located away from the floor, helping eliminate the possibility of water coming in contact with electricity.
• Boiler built to ASME Section 1, High Pressure Boiler Code.CSD-1 approved.
• Burner/Boiler UL Packaged.