Suggested Specification for Centauri Duplex Alloy Condensing Water Boiler:
1500-2000MBTUH
SECTION 15514 OR SECTION 23 52 39
PART 1 - GENERAL
1.1 RELATED DOCUMENTS
Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this section.
1.2 SUMMARY
This section includes condensing gas-fired medium mass boilers for non-potable water.
1.3 REFERENCES
A. ASME Boiler and Pressure vessel code, section IV
B. UL 795 “Industrial Gas Heating Equipment”
C. ASHRAE/IES 90.1-2010
D. ISO 9001 Quality Management System
E. CSD-1-2009 “Controls and Safety Devices for Automatically Fired Boilers”
F. NFPA 70- National Electric Code
G. NFPA 54- National Fuel Gas Code
H. ASTM G123 - 00(2005) “Standard Test Method for Evaluating Stress-Corrosion Cracking of Stainless Alloys with Different Nickel Content in Boiling Acidified Sodium Chloride Solution.”
I. ANSI Z21.13 "Standard for durability, safety and minimum efficiency guidelines for heating hot water boilers."
1.4 SUBMITTALS
A. Product Data: Include rated capacities; shipping, installed, and operating weights; furnished specialties and accessories for each model indicated.
B. Shop Drawings: Detail equipment assemblies and indicate dimensions, required clearances, components, and size of each field connection.
C. Wiring Diagrams: Detail for wiring power signal, differentiate between manufacture- installed and field-installed wiring.
D. Field Test Reports: Indicate and interpret test reports for compliance with performance requirements. A copy shall be furnished to the owner.
E. Maintenance Data: Include in the maintenance manuals specified in Division 1. Include maintenance guide and wiring diagrams.
1.5 REGULATORY REQUIREMENTS
A. Conform to applicable code for internal wiring of factory wired equipment.
B. ETL, UL or CSA Certified as a Complete Gas Fired Boiler Assembly.
C. Gas Train shall comply with UL 795.
D. Conform to ASME Section IV.
1.6 QUALITY ASSURANCE
A. Boiler shall bear the ASME stamp and be National Board listed.
B. Thermal efficiency of the boiler shall be 86% when tested to the requirements of the Department of Energy as codified in 10 CFR 431.
C. The boiler shall comply with current ASHRAE 90.1 requirements.
D. Boiler manufacturer shall be certified to the ISO 9001 International Quality System.
1.7 COORDINATION
Coordinate size and location of concrete bases.
PART 2 - PRODUCTS
2.1 MANUFACTURERS
A. Manufacturer shall be a company that has achieved certification to ISO 9001 Quality Management System and specializes in manufacturing the products specified in this section.
B. Acceptable manufacturers shall be subject to compliance with the requirements
described in the specification.
2.2 VENT REQUIREMENTS AND CAPABILITIES
A. The boiler shall vent through a Category IV, positive pressure vent using AL29-4C stainless steel material. The appliance shall be capable of drawing remote combustion air through up to 100 equivalent feet of 6 inch PVC or galvanized vent pipe.
B. The manufacturer’s representative that provides the boiler specified in this section shall also size, select and provide a venting system that is recommended and approved by the boiler manufacturer.
2.3 PRESSURE VESSEL CONSTRUCTION
A. The boiler shall be constructed from phase-balanced austenitic and ferritic duplex alloy with a chemical structure containing a minimum of 21% chromium to prevent corrosion and mill certified per ASTM A 923Methods A to ensure that the product is free of detrimental chemical precipitation that affects corrosion resistance. The material selected shall be tested and certified to pass stress chloride cracking test protocols as defined in ISO 3651-2and ASTM G123 - 00(2005) “Standard Test Method for Evaluating Stress-Corrosion Cracking of Stainless Alloys with Different Nickel Content in Boiling Acidified Sodium Chloride Solution.”
B. Waterside surfaces shall be welded internally utilizing joint designs to minimize volume of weld deposit and heat input. All heat-affected zones (HAZ) shall be processed after welding to ensure the HAZ corrosion resistance is consistent with the mill condition base metal chemical composition. Weld procedures (amperage, volts, welding speed, filler metals and shielding gases) utilized shall result in a narrow range of austenite-ferrite microstructure content consistent with phase balanced objectives for welds, HAZ and the base metal.
C. All internal and external tank surfaces shall undergo full immersion passivation and pickling processing to meet critical temperature, duration and chemical concentration controls required to complete corrosion resistance restoration of pressure vessel surfaces. Other passivation and pickling methods are not accepted. Immersion passivation and pickling certification documents are required and shall be provided with each product.
D. Pressure vessel shall include a hand hole cleanout.
E. The pressure vessel shall be National Board Registered for a working pressure of 80 psig and shall be pressure tested at 1 1/2 times working pressure.
F. The pressure vessel materials shall contain more than 80% post-consumer recycled materials and be 100% recyclable.
2.4 BURNER CONSTRUCTION AND PERFORMANCE
A. The boiler shall fire on natural gas or LP (optional).
B. Thermal efficiency of the boiler shall be 86% when tested to the requirements of the Department of Energy as codified in 10 CFR 431.
C. Efficiency shall be at least 86.5% at high-fire with a 110º hot water return.
D. The burner shall be woven metal matrix surface type producing a 360-degree flame pattern.
E. Pre-mix burner shall include a proportional gas/air control and variable speed blower motor.
F. Electronic ignition control shall operate with pre-and post purge cycles.
G. Shall be CSD-1 & FM compliant.
H. Shall be Intertek/ETL listed to U.S. and Canadian standards.
I. The boiler shall be SCAQMD certified.
J. Burner shall be fully modulating and capable of a 5:1 turndown ratio or higher.
K. Burner shall continuously and automatically synchronize fuel and air for optimum combustion under varying vent pressure an atmospheric conditions.
L. Shall have dual temperature limits with manual reset on high-limit temperature control.
2.5 BOILER TRIM
A. Pressure vessel shall be insulated with 3 inches of heavy density fiberglass. The
boiler shall fit properly in the space provided and the installation shall conform to all
local, state and national codes. The steel jacket shall be coated with baked-on finish.
B. Controls and operating features shall include the following:
1. Electronic ignition control with pre- and post-purge.
2. Electronic operating control with digital readout.
3. Firing cycle status panel lights.
4. Dual temperature limits with manual-reset on high-limit temperature control.
5. Manual-reset, electronic low-water cutoff with test switch. (no lockout on power loss)
6. Flame failure audible alarm (72db) and indicating panel light with remote dry contacts.
7. Pressure gauge on tank.
8. High and low gas pressure switches.
9. Maximum 210 degrees F operating limit.
10. Combustion air filter.
11. MODBUS protocol on operating control through a 485 serial connection. (optional cable required)
12. Remote on/off terminals.
13. Remote 4-20mA or 0-10V modulation control terminals.
2.6 WARRANTY
The pressure vessel and heating tubes shall have a non-prorated, 10-year manufacturer's limited warranty against failure due to manufacturing defect, material defect, chloride stress cracking and thermal shock. Boiler shall be provided with a service advantage plan that shall cover freight and labor for a warranty covered repair or replacement for one year. Boiler shall be provided with an extended service advantage plan (optional) that shall cover freight and labor for a warranty covered repair or replacement for 10 years.
PART 3 - EXECUTION
3.1 INSTALLATION
Install boilers level and plumb in accordance with manufacturer's written instructions and referenced standards.
3.2 FINISHING
The boiler shall be completely factory packaged on a single skid, requiring only job site hookup to utilities, venting and plumbing. All gas train components shall be accessible and able to adjust without the removal of the cabinet components. The boiler shall be insulated to ASHRAE 90.1-2010 requirements, jacketed with coated steel panels and mounted on heavy-duty channel skids. The boiler shall fit properly in the space provided and installation shall conform to all local, state, and national codes.
3.3 START-UP
Start-up on the unit shall be performed by factory trained and authorized personnel. A copy of the start-up report shall be provided to the owner. The report shall include a printout from the flue gas analyzer which shall identify values of efficiencies, related inlet and outlet temperatures and percentages of effluent contents. The report shall also include written verification that all safety controls are functioning as intended and the venting and make-up air systems are in compliance with factory guidelines.
Duplex Alloy Centauri 1500to2000MBTUH 05/10/12