Hot water generating systems; vertical and horizontal (20 pages)
Summary of Contents for A.O. Smith NW 37-670
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Service • Maintenance TEXT PRINTED OR OUTLINED IN RED CONTINS INFORMATION RELATIVE TO YOUR SAFETY. PLEASE READ THOROUGHLY BEFORE INSTALLING AND USING THE APPLIANCE. A DIVISION OF A.O. SMITH CORPORATION RENTON, WASHINGTON • Limited Warranty CAUTION www.hotwater.com PART NO. 60047-002 REV.2...
DIMENSIONAL DATA Model Number Prefix Gal.Cap. Std.KWInput 105K 120K 150K 180K 210K 240K 270K 300K 330K 390K 420K 450K 480K 540K 600K 660K 720K * All fittings under 4” will be threaded type. All fittings 4” and larger will be flanged. 3” fittings extend 4” beyond jacket. ** Where overall height is a problem a larger diameter vessel with a reduced height may be furnished.
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Model Number Prefix Gal.Cap. Std.KWInput 780K 840K 900K 960K 1020K 1080K 1140K 1200K 1260K 1380K 1500K 1620K 1740K 1800K 1860K 1980K 2100K 2200K 2340K 2460K 2580K 2700K 2820K 2940K 3060K 3180K 3300K NOTE: For boilers 3400KW to 6000KW, consult factory. * All fittings under 4”...
FOREWORD APPROVALS These designs comply with requirements of Underwriters Laboratories and bear the U.L. label on the cabinet. All models are built to the standards of Section lV of the American Society of Mechanical Engineers. Boiler and Pressure Code, inspected and identified by this symbol. The ASME plate is located on the tank above the cleanout opening.
IMPORTANT IT IS RECOMMENDED THAT A QUALIFIED SERVICE TECHNICIAN PERFORM THE INITIAL FIRING OF THE BOILER. AT THIS TIME THE USER SHOULD NOT HESITATE TO ASK THE TECHNICIAN ANY QUESTIONS WHICH THEY MAY HAVE IN REGARD TO THE OPERATION AND MAINTENANCE OF THE BOILER. BEFORE FILLING THE SYSTEM FOR OPERATION the hot water system should be internally cleaned and flushed to remove any contaminants which may have accumulated during installation.
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Calculating Amperage/Overcurrent Protection The boiler is factory wired for connection to three wire single-phase or three and four wire three-phase branch circuits. In addition, a ground conductor may be required. A diagram of the wiring is furnished with the boiler for the electrician’s use.
Boiler Type Nameplate Markings Service Voltage Phase Delta (With Neutral) Delta Wye* Delta * Neutral lug not necessary and not furnished due to three wire wye connection. This means only three wires (no neutral) brought to boiler due to method of element connection. Elements operate at 277 volts. Voltage from a conductor to ground (electrical raceway and water pipes) is not measured.
SYSTEM CLEANING The hot water system should be internally cleaned and flushed to remove contaminants which may have accumulated during installation. System cleaning provides chemical stability necessary for component life and system performance. Failure to clean the system may cause: 1.
4. Close the vent as water starts to flow from the opening. Place the make-up water valve in the desired position. The boiler is now ready for START UP and TEMPERATURE REGULATION if being placed in operation for the first time. START UP The following checks should be made by the installer when the boiler is placed into operation for the first time:...
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• Use a twisting, pulling action to remove elements scaled beyond the size of the tank opening. • Brush loose scale from elements. • Silicates, sulfates and aluminates must be removed by scraping or other mechanical means. Lime scale dissolvents will not remove these types of scale which are occasionally encountered.
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Some government agencies are requiring energy efficient standards for boilers. In the event regulations prohibit sale of a model of equivalent size and construction, A.O. Smith will provide a model which the regulations of your area, in which case the consumer will be charged the difference in price between the like replacement and the energy efficient model required.