HORIZONTAL FIRE TUBE BOILERS Piping (HVAC) Pumping Equipment (HVAC).

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1 SECTION HORIZONTAL FIRE TUBE BOILERS PART 1 GENERAL 1.01 SUMMARY A. Related Sections: Piping (HVAC) Pumping Equipment (HVAC) SUBMITTALS A. Submit properly identified manufacturer's catalog cuts and technical data before starting work. B. Shop Drawings: Controls. PART 2 PRODUCTS 2.01 MANUFACTURERS A. Horizontal Fire Tube Type Boiler: 1. Cleaver Brooks Co. 2. Continental. 3. York Shipley. B. Air Eliminators: 1. Bell and Gossett. 2. Taco EQUIPMENT A. Horizontal Fire Tube Type Boiler: 1. Provide with 5 square feet of heating surface per horsepower. 2. Mount on heavy steel base frame and deliver complete with integral forced draft burner, burner controls, boiler trim, and refractory. 3. Complete unit shall be listed by Underwriters Laboratories and shall bear UL label. B. Boiler Shell: Project No. SPECIFICATION GUIDELINES

2 1. The boiler shell shall be designed, constructed, and hydrostatically tested according to the ASME Boiler and Pressure Vessel Code. 2. Design for hot water operation with temperatures not exceeding 250 degrees F. and 125 psi working pressure, constructed according to Section IV titled Low Pressure Heating Boilers. 3. Provide with necessary number of handholes and complete with manhole and lifting eyes permanently attached at top of boiler. a. Hinge doors at front and rear of boiler, sealed and tightly fastened. b. Provide observation ports for the inspection of flame conditions at each end of boiler. c. Front and rear tube sheets shall be fully accessible for inspection and cleaning when doors are opened. 4. Insulate boiler with a 2-inch fiberglass blanket under a sectional preformed sheet metal lagging that can be readily removed and installed. Rear refractory and insulation shall be contained in the formed rear door. 5. Locate exhaust gas vent near the front of the boiler on the top center line with a stack thermometer. 6. Factory paint the entire boiler, base, frame, and other components before shipment using a hard finish heat resistant enamel. 7. Perform an authorized factory boiler inspection before shipment to job site. A copy of the boiler inspection shall be provided for review by the A/E. C. Boiler Accessories includes but is not limited to: 1. Hot water outlet and return connections flanged with 150 pound flanges. 2. Low water cutoff mounted on the side of the unit. 3. Pressure and temperature gages. 4. Relief valves of type and size to comply with ASME code mounted on unit and piped to the floor drain. 5. Temperature controls to regulate burner operation mounted on the unit and a drain valve at the rear drain connector. 6. Pressure regulator in gas train. D. Forced Draft Blower: 1. Provide a forced draft blower mounted in the front boiler door. Project No. SPECIFICATION GUIDELINES

3 a. Impeller: Cast aluminum radial blade directly connected to the blower motor shaft. b. Adjustment: Manually by a damper. 2. Damper and butterfly gas valve shall be controlled by a damper motor. E. Burner: 1. Provide a high radiant annular entry type burner approved for operation with natural gas. 2. Burner shall operate on full modulation principle, and shall always return to the low fire position for ignition. 3. Gas pilot shall be of the Premix type with automatic electric ignition. An electronic detector shall monitor the pilot so that the primary gas valve cannot open until the pilot flame has been established. 4. Gas burner piping shall conform with FIA requirements. F. Gas System: 1. Gas burner piping on the unit shall include a primary gas cutoff valve. a. It shall be controlled by the programming relay to start or stop the burner and to close automatically upon power failure, flame failure, or a low water condition. Connect the valve to an unobstructed emergency cutoff switch within 2 feet of the interior side of the entry door. b. An additional valve of the lubricated plug type shall be located ahead of the primary gas valve for manual cutoff. 2. A plugged leakage test cock and a second lubricated plug cock shall be provided for a tightness check of the primary cutoff valve. 3. A proof of closure switch shall be provided on the primary cutoff valve, and high and low gas pressure switches shall be provided. G. Burner Flame Failure Controller: 1. The program relay shall control ignition, starting and stopping of the burner and provide both a precombustion purge and a post-combustion purge. 2. It shall shut down the burner upon ignition, pilot, or main flame failure. 3. Provide a flame failure alarm bell. Project No. SPECIFICATION GUIDELINES

4 H. Control Panel: 1. Mount the control panel on the front door of the boiler. 2. It shall be a NEMA IA enclosure, conveniently located for the operator. Include electronic programming relay, blower motor starter, and control switches within the panel. 3. Provide a manual-automatic switch to allow continuous firing at the low fire or high fire rate when automatic firing is not needed. 4. All electrical equipment shall be according to UL requirements. Use oil, heat, and moisture resistant wire throughout. I. Vent Line: Run vent line to outside of building as approved by the local codes with schedule 40 galvanized pipe. J. Operating Efficiency: Guarantee complete unit to operate at minimum fuel to hot water efficiency. K. Vertical Stack: 1. Size as indicated on Construction Documents or manufacturer's recommendation, constructed of 10 gage black steel continuous welded construction. 2. Provide insulated thimble at roof penetration and rain cap. L. Air Eliminators: 1. Construct of steel with flanged connections, internal stainless steel air collector tube, and removable system strainer of galvanized steel with 3/16" perforations. 2. Construction: According to ASME and stamped 125 psi working pressure. Provide blow down connection SOURCE QUALITY CONTROL A. Shop Tests: The packaged boiler must receive factory tests to check the construction, controls, and operation of the unit. All tests may be witnessed by the Board, if desired. PART 3 EXECUTION 3.01 INSTALLATION Project No. SPECIFICATION GUIDELINES

5 A. Install according to manufacturer's printed installation instructions and accepted Shop Drawings FIELD QUALITY CONTROL A. Manufacturer's Field Service: After the boiler installation is completed, furnish the services of a factory authorized field representative for starting the boiler and training the Board's authorized operators. 1. Continue training service until the boiler is proven to be functioning and cycling properly. END OF SECTION Project No. SPECIFICATION GUIDELINES