SECTION 223436.23 – HIGH EFFICIENCY GAS DOMESTIC WATER HEATERS
PART 1 - GENERAL
1.1 RELATED DOCUMENTS
A. Drawings and general provisions of the Contract apply to this Section, including General and Supplementary Conditions and Division01 Specification Sections.
1.2 SUMMARY
A. This Section includes gas-fired, high efficiency condensing domestic water heaters for potable water.
1.3 SUBMITTALS
A. Product Data: Include rated performance data, operating characteristics, electrical characteristics, furnished specialties and accessories.
B. Shop Drawings:
1. Wiring Diagrams for power, signal and control wiring
C. Operation and Maintenance Data: To be included in water heater emergency, operation and maintenance manuals.
D. Warranty: Five-year non-prorated warranty coverage on water heater water vessel and heat exchanger as specified in Part 1.6 – Warranty.
E. ASME Stamp label.
1.4 QUALITY ASSURANCE
A. Electrical Components, Devices and Accessories: Condensing water heaters must be listed and labeled as defined in NFPA70 by a testing agency acceptable to authorities having jurisdiction, and marked for intended use.
B. Performance Compliance: Condensing water heaters must be rated in accordance with ASHRAE 118.1 testing methods and verified by UL or AHRI as capable of achieving the energy efficiency and performance ratings as tested within prescribed tolerances.
C. ASME Compliance: Condensing water heaters must be constructed in accordance with ASME Water heater and Pressure Vessel Code, Section IV (HLW) Potable Water Heaters.
D. ASHRAE/IESNA90.1 Compliance: Condensing water heaters shall have minimum efficiency according to "Gas and Oil Fired water heaters - Minimum Efficiency Requirements," when tested in accordance with Section G.1 “Method of Test for Measuring Thermal Efficiency” and G.2 “Method of Test for Measuring Standby Loss” of ANSI Z21.10.3
E. NOx Emission Standards. When installed and operated in accordance with manufacturer’s instructions, condensing water heaters shall comply with the NOx emission standards outlined in South Coast Air Quality Management District (SCAQMD), Rule 1146.2; and the Texas Commission on Environmental Quality (TCEQ), Title 30, Chapter 117, Rule 117.465.
F. Low Lead Compliance: Condensing water heaters must be third party classified to meet the requirements of ANSI/NSF 372, hence that the weighted average of the wetted surface area in contact with potable water must be no greater than 0.25% lead content.
1.5 COORDINATION
A. Coordinate size and location of concrete bases as defined in condensing water heater Installation and Operation Manual.
1.6 WARRANTY
A. Standard Warranty: Water heaters shall include manufacturer's standard form in which manufacturer agrees to repair or replace components of water heaters that fail in materials or workmanship within specified warranty period.
1. Specified Warranty Period Condensing Storage Water heaters:
The water storage tank and heat exchanger shall be conditionally guaranteed against leakage for a period of five-years from date of installation.
All other components are conditionally guaranteed against any failure for a period of twelve months from date of installation.
PART 2 - PRODUCTS
2.1 MANUFACTURERS
A. Available Manufacturers: Subject to compliance with requirements, manufacturers offering products that may be incorporated into the Work include, but are not limited to, the following:
B. Manufacturers: Subject to compliance with requirements, provide products by one of the following:
C. Basis-of-Design Product: Subject to compliance with requirements, provide BOCK optiTHERM, Model: OT500N-A (natural gas)____; OT500LP-A (liquid propane gas)____; OT400N-A (natural gas) ____; OT400LP-A (liquid propane gas) ____; OT300N-A (natural gas) ____; OT300LP-A (liquid propane gas) ____; OT299N-A (natural gas)____; OT299LP-A (liquid propane gas)____; OT250N-A (natural gas) ____; OT250LP-A (liquid propane gas) ____; OT200N-A (natural gas) ____; OT200LP-A (liquid propane gas) ____; OT199N ____; (natural gas); OT199LP ____; (liquid propane gas); OT150N ____; (natural gas); OT150LP ____; (liquid propane gas); OT125N ____; (natural gas); OT125LP ____; (liquid propane gas) or, a comparable product by one of the following:
1. Bock Water Heaters, Inc.
2. ______
3. ______
2.2 CONSTRUCTION
A. General: The water heater shall have a total recovery of ______GPH, (_____ GPM) at a _____oF temperature rise. Each water heater shall be UL Listed; and, ASME Section IV (HLW) coded and stamped. Each unit shall operate with ASHRAE 118.1 efficiency of not less than 93% at full fire and not less than 97% at minimum fire. System shall consist of a quantity of Water Heaters Model:
___OT500N-A, each with an input of 500,000BTU and be fully modulating to a minimum input of 135,000BTU.
___OT500LP-A, each with an input of 500,000BTU and be fully modulating to a minimum input of 135,000BTU.
___OT400N-A, each with an input of 399,999BTU and be fully modulating to a minimum input of 135,000BTU.
___OT400LP-A, each with an input of 399,999BTU and be fully modulating to a minimum input of 135,000BTU.
___OT300N-A, each with an input of 300,000BTU and be fully modulating to a minimum input of 135,000BTU.
___OT300LP-A, each with an input of 300,000BTU and be fully modulating to a minimum input of 135,000BTU.
___OT299N-A, each with an input of 299,999BTU and be fully modulating to a minimum input of 76,000BTU.
___OT299LP-A, each with an input of 299,999BTU and be fully modulating to a minimum input of 76,000BTU.
___OT250N-A, each with an input of 250,000BTU and be fully modulating to a minimum input of 76,000BTU.
___OT250LP-A, each with an input of 250,000BTU and be fully modulating to a minimum input of 76,000BTU.
___OT200N-A, each with an input of 199,999BTU and be fully modulating to a minimum input of 76,000BTU.
___OT200LP-A, each with an input of 199,999BTU and be fully modulating to a minimum input of 76,000BTU.
B. Description: Water heater shall be direct fired with modulating pre-mix burner, shall be fully condensing, shall have heat exchanger integrated within the water storage vessel as a unitized structure, and, shall have Impressed Current Cathodic Protection. Power burner shall have full modulation and a minimum firing rate not to exceed 135,000BTU/HR input. Water heaters not having fully modulating input, or, not of unitized heat exchanger integrated within water storage vessel construction, or, not having Impressed Current Cathodic Protection will not be considered equal.
C. Heat Exchanger: The heat exchanger shall be a three-pass configuration integrated within the water storage vessel and shall consist of a dual stage Turboflue® helical fin flue heat exchanger and third-pass glass-lined condensing flues with stainless steel baffles.
D. Water Storage Vessel: The water storage vessel shall be fabricated from carbon steel and have a glass lining bonded to the tank interior by firing at 1500°F to ensure a molecular fusing of glass and steel.
E. Corrosion Control: CORREX® Impressed Current Cathodic Protection technology shall provide automated corrosion control to the water contact surface of the heat exchanger and water storage vessel.
F. Modulating Air/Fuel Valve and Burner: The water heater burner shall be capable of operating between its rated maximum Input and its rated minimum Input at a continuous variable turndown without loss of combustion efficiency. The burner shall not exceed 20ppm of NOx corrected to 3% excess oxygen.
PART 3 - EXECUTION
3.1 WATER HEATER INSTALLATION
A. Install water heaters level on concrete bases. Concrete base is specified in Division23 Section "Common Work Results for HVAC," and concrete materials and installation requirements are specified in Division03.
B. Install gas-fired water heaters in accordance with
1. All applicable codes, laws, regulations, and ordinances.
2. National Fuel Gas Code, ANSI Z223.1/NFPA 54 – latest edition.
3. National Electrical Code, ANSI/NFPA 70 - latest edition.
4. Canada only: CAN/CGA B149 Installation Code and CSA C22.1 CEC Part 1.
5. Manufacturer’s installation instructions, including required service clearances, and condensate plumbing and venting guidelines.
C. Fill water heaters with water.
D. Activate 120V, 60 Hz electrical power to water heaters.
3.2 CONNECTIONS
A. Piping installation requirements are specified in other Division23 sections. Drawings indicate general arrangement of piping, fittings and specialties.
B. Install piping adjacent to water heater to permit service and maintenance.
C. Install piping from equipment drain connection to nearest floor drain. Piping shall be at least full size of connection. Provide an isolation valve if required.
D. Connect gas piping to water heater gas-train inlet with unions. Piping shall be at least full size of the gas train connection.
E. Connect hot-water piping to supply and return water heater tapings with shutoff valve and union or flange at each connection.
F. Multiple heaters shall be piped first-in, last-out (i.e. reverse return).
G. Install piping from safety relief valves to nearest floor drain.
H. Install water heater Venting:
1. According to venting requirements stated in water heater installation and operation manual.
2. Comply with requirements in Division23 Section "Breechings, Chimneys and Stacks.
I. Ground equipment according to Division26 Section "Grounding and Bonding for Electrical Systems."
J. Connect wiring according to Division26 Section "Low-Voltage Electrical Power Conductors and Cables."
3.3 IDENTIFICATION
A. Identify system components. Comply with requirements for identification specified in Division 22 Section “Identification for Plumbing Piping and Equipment.”
3.4 FIELD QUALITY CONTROL
A. Perform tests and inspections and prepare test reports.
1. Manufacturer's Field Service: Engage a factory-authorized service representative to inspect components, assemblies and equipment installations, including connections, and to assist in testing.
B. Tests and Inspections
1. Installation and Startup Test: Perform installation and startup checks according to manufacturer's written instructions.
2. Leak Test: Perform hydrostatic test. Repair leaks and retest until no leaks exist.
3. Operational Test: Start units to confirm proper operation.
4. Controls and Safeties: Test and adjust controls and safeties. Replace damaged and malfunctioning controls and equipment.
3.5 DEMONSTRATION
A. Engage a factory-authorized representative to train owner’s maintenance personnel to adjust, operate, and maintain commercial, gas-fired, storage domestic-water heaters.
END OF SECTION 223436.23