National Products BW3 Installation, Start-up, And Operating Instructions Manual

Manual is about: Series B Gas-Fired Induced-Draft Hot Water Boilers

Summary of BW3

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    Note: read the entire instruction manual before starting the installation. These instructions must be affixed on or adjacent to the boiler. This symbol → indicates a change since the last issue. Index page safety considerations............................................................................

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    Chimney and vent pipe connection .......................................................................................................................................................7-9 checking chimney...................................................................................................

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    Introduction this boiler cannot be used with all types of chimneys. Read these instructions carefully before installing. These gas-fired hot water boilers are low-pressure, sectional cast iron boilers design certified by the american gas association (a.G.A.) and canadian gas association (c.G.A.) for...

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    Canada only—for altitudes in the range of 2000-4500 ft above sea level, boilers may be field equipped for use at high altitude by using a certified field conversion kit. The change in main burner orifice size results in boiler’s input rating being reduced by 10 percent. The conversion shall be carri...

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    7. Table 2 shows minimum clearances from combustible materials. 8. Equipment shall be installed in a location in which the facilities for ventilation permit satisfactory combustion of gas, proper venting, and maintenance of ambient temperature at safe limits under normal conditions of use. Equipment...

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    Equipment located in buildings of unusually tight construction shall be provided with air for combustion, ventilation, and dilution of flue gases using the methods described in example 2b or shall be specially engineered. The authority having jurisdiction must approve specially engineered installati...

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    Installation—system piping 1. Place boiler in selected location (as close to chimney as possible). Boiler is shipped assembled. Only the relief valve with a drain line to carry any water to a drain and a drain valve need to be installed. 2. Install relief valve on 3/4-in. Pipe nipple in tapped openi...

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    2. The boiler’s induced draft blower has a 3-in. Outlet. A 3-in. X 4-in. Increaser fitting is included in the parts bag. Locate increaser fitting on outlet of induced draft blower and secure gastight with a bead of the factory-supplied silicone sealant. The increaser fitting is required on this boil...

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    For boilers with connections to gas vents or chimneys, vent installations shall be in accordance with part 7 nfgc, venting of equipment, in the united states or part 7 nscngpuc, venting system and air supply for appliances in canada, and applicable provisions of local building codes. Vent connectors...

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    3. Boiler installation site experiences gusting or high winds. A power venter can help prevent the boiler from short cycling due to gusting or high winds by providing vent exhaust pressures greater than the boiler’s induced draft blower alone. 4. When installer or homeowner prefers a negative pressu...

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    4. Install a sediment trap upstream of gas controls. 5. Use 2 pipe wrenches when making connection to gas valve to keep it from turning. 6. Install a manual shutoff valve in vertical pipe about 5 ft above floor. 7. Tighten all joints securely. 8. Propane gas connections should only be made be a lice...

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    Fig. 7—unit wiring diagram note: if any of the original wire as supplied with the boiler must be replaced, it must be replaced with the same wire or its equivalent. A96142 l1 l2 l1 3 b r l2 t t c1 c2 b1 b2 b1 r b b2 c2 c1 3 t t 24 v. Secondary 24 v. Thermostat circulator draft inducer overcurrent pr...

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    4. When blower gets up to speed and blower suction pressure reaches pressure switch setpoint, pressure switch contacts close sending 24v to s8600 intermittent pilot control from at 140c transformer secondary. 5. Pilot gas valve opens, and spark initiates to light pilot burner. 6. When pilot flame is...

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    Procedure 9—circulating pump every forced hot water system requires a circulating pump. A separate pump or zone valve is required for each zone if there are 2 or more zones. This pump must have the capacity to provide circulation required by system. The pump is connected into return main just ahead ...

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    Before operating, smell all around appliance area for gas. Be sure to smell next to the floor because some gas is heavier than air and will settle on the floor. Warning: if you smell gas: • do not attempt to operate any appliance; do not touch any electric switch; do not use any phone in your buildi...

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    Checking and adjusting procedure 1—gas valve safety shutdown test with main burners firing, disconnect ignition cable from intermittent pilot control box. Gas valve should shut off main burners. Turn off electric power to boiler before reconnecting ignition cable to prevent electric shock. Procedure...

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    Maintaining boiler procedure 1—burners a visual check of pilot and main burner flames should be made at least once each year, preferably at beginning of heating season. See checking and adjusting section and fig. 9, 11, and 12. Main burner flame should form a sharp blue cone with no yellow. Procedur...

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    12. Be sure to check tightness of pilot connections and condition of burner flames after reassembly. (see fig. 11.) 13. Be sure vent pipe connections to chimney are secure and no obstructions are present. Procedure 8—blower the blower motor features permanently lubricated ball bearing construction. ...

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    Repair parts important — read these instructions before ordering all parts listed in the following parts list may be ordered through your nearest supplier. When ordering parts, first obtain the model no. From the data plate on boiler, then determine the part no. (not the key no.) and the description...

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    Repair parts propane gas burners and manifold parts this is a repair parts list—not a packing list key no. Description part no. 2 section 3 section 4 section 5 section 6 section 7 section 1 24-v gas valve, propane gas 146-62-062 146-62-062 146-62-062 146-62-062 146-62-059 146-62-059 2 pilot tube 146...

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    → repair parts jacket—section and base parts this is a repair parts list—not a packing list key no. Description part no. 2 section 3 section 4 section 5 section 6 section 7 section 1 jacket, right side panel 730-00-1050 730-00-1050 730-00-1050 730-00-1050 730-00-1050 730-00-1050 2 blower cover plate...

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    Repair parts key no. Description part no. 1 3/4-in. Asme relief valve 146-22-011 2 3/4-in. X 5-1/2-in. Nipple 146-07-040 3 temperature-pressure gage—3-1/2-in. Shank 146-23-007 4 1-1/4-in. X 5-1/2-in. Nipple 146-07-019 5 1-1/4-in. X 3/4-in. X 1-1/4-in tee 146-93-049 6 l8148a combination hi limit and ...

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    A94328 service training packaged service training programs are an excellent way to increase your knowledge of the equipment discussed in this manual, including: • unit familiarization • maintenance • installation overview • operating sequence a large selection of product, theory, and skills programs...

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    © 1999 cac/bdp p.O. Box 70, indianapolis, in 46206 imbw3a05 —24— catalog no. 63bw-3a1.