Installation, Start-Up, and Operating Instructions Gas-Fired Induced-Draft Hot Water Boilers Sizes 42,500 through 225,000 BW3 Series B ama CERTIFIED ® ASME 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. MODEL BW3 A03117 Index Page SAFETY CONSIDERATIONS........................................................................................................
CHIMNEY AND VENT PIPE CONNECTION .......................................................................................................................................................7-9 Checking Chimney ................................................................................................................................................................................................7-8 Minimum Vent Pipe Clearance....................................................................................
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 CSA International (A.G.A. and C.G.A.) for use with natural and propane gases. They are constructed and hydrostatically tested for a maximum working pressure of 50 psi in accordance with the American Society of Mechanical Engineers (A.S.M.E.
1 1⁄4" SUPPLY A RELIEF VALVE 23 1⁄4" VENT CONNECTOR COMBINATION LIMIT & RELAY CONTROL TEMP PRESSURE GAGE BLOWER 29" 25 1⁄4" 23" 5 5⁄8" PRESSURE SWITCH 5 5⁄8" 1 3⁄4" BURNER GAS VALVE 7" LEFT SIDE FRONT 1 1⁄4" RETURN INT. PILOT CONTROL RIGHT SIDE A02317 Gas-Fired Hot Water Boilers BOILER MODEL NUMBER* BW3AAN000042ABAA BW3AAN000075ABAA BW3AAN000112ABAA BW3AAN000150ABAA BW3AAN000187ABAA BW3AAN000225ABAA → NO. OF SECTIONS 2 3 4 5 6 7 NATURAL AND PROPANE GAS† Net A.G.A.
Table 1—Room Large In Comparison With Boiler BOILER SIZE (SECTIONS) BOILER VOLUME (CU FT) 2 3 4 5 6 7 4.3 5.6 6.8 8.1 9.4 10.6 MINIMUM ROOM VOLUME REQUIRED TO BE LARGE ROOM (CU FT)* 68.7 89.0 109.3 129.5 149.8 170.1 * For room with single boiler only. Table 2—Minimum Clearances From Combustible Materials and For Servicing PART OF BOILER Top Rear Control Side Opposite Control Side Front Flue/Vent Connector Boiler Piping ALCOVE OR ROOM NOT LARGE IN COMPARISON WITH BOILER (IN.
PROCEDURE 2—BOILER LOCATED IN CONFINED SPACE EXAMPLE 2A: ALL AIR FROM INSIDE THE BUILDING The confined space shall be provided with two permanent openings communicating directly with an additional room(s) of sufficient volume so that combined volume of all spaces meets criteria for an unconfined space. The total input of all gas utilization equipment installed in combined space shall be considered in making this determination.
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 opening in left end section. Connect a drain line of same pipe size (3/4 in.) to carry any water away to a drain.
TO SYSTEM A B C D WATER CHILLER VALVES C & D CLOSE FOR HEATING; OPEN FOR COOLING → VALVES A & B OPEN FOR HEATING; CLOSE FOR COOLING A03120 Fig. 4—Piping Arrangements for Boiler Used in Connection with Refrigeration System 2. The boiler’s induced draft blower has a 3-in. outlet. A 3-in. X 4-in. increaser fitting is included in parts bag. Locate increaser fitting on outlet of induced draft blower and secure gastight with a bead of the factory-supplied silicone sealant.
; ;; ; THE VENT PIPE MUST BE AT LEAST 2 FT HIGHER THAN ANY PART OF THE ROOF WITHIN A 10 FT RADIUS OF THE VENT. LINER CHIMNEY THIMBLE 10' 2' MIN 3' MIN VENT SYSTEM CLEANOUT SHEET METAL FIRESTOP A95196 Fig.
3. Boiler installation site experiences gusting or high winds. A power venter can help prevent 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 pressure vent system instead of a positive pressure vent system. 5. May be more cost effective than stainless steel venting, particularly at longer vent lengths.
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 by a licensed propane installer. 9. Two-stage regulation should be used by propane installer. 10. Propane gas piping should be checked be propane installer.
—12— 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.
SEQUENCE OF OPERATION 1. Thermostat calls for heat, powering 1K relay coil and closing contacts 1K1 and 1K2. 2. Circulator pump is powered through terminals C1 and C2. 3. Induced draft blower and AT 140C transformer primary are powered through terminals B1 and B2. 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.
PROCEDURE 8—WATER TEMPERATURE CONTROL The water temperature limit control in relay is adjustable and may be set as necessary. It may be set as low as 140°F or as high as 240°F. Setting depends on type and amount of radiation involved and weather conditions. 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 capacity to provide circulation required by system.
BEFORE OPERATING, smell all around appliance area for gas. Be sure to smell next to 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 building. • Leave the building immediately and call your gas supplier. • If your gas supplier cannot be reached, call the fire department. WARNING: When turning gas control knob, use only your hand to turn knob.
PRESSURE REGULATOR ADJUSTMENT (UNDER CAP SCREW) WIRING TERMINALS (3) INLET PRESSURE TAP 3⁄8″ GAS INLET to 1⁄2″ OUTLET PRESSURE TAP GROUND TERMINALS (2) ON FLAME ON SENSOR GAS OUTLET OFF GAS CONTROL KNOB SHOWN IN "ON" POSITION PILOT ADJUSTMENT (UNDER CAP SCREW) A95160 PILOT OUTLET A95520 Fig. 10—Automatic Gas Valve Fig.
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. PROCEDURE 2—RELIEF VALVE This valve should open automatically when system pressure exceeds pressure rating (usually 30 psi) of relief valve. Should it ever fail to open under this condition, shut down system.
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. Lubrication is not required. SERVICE HINTS You may avoid inconvenience and service calls by checking these points before you call for service. FOR YOUR SAFETY WHAT TO DO IF YOU SMELL GAS 1. 2. 3. 4. Do not try to light any appliance. Do not touch any electric switch; do not use the phone.
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 Model No. from data plate on boiler, then determine Part No. (not Key No.) and Description of each part from the following illustrations and lists. Be sure to give all this information: Part No. — Part Description — Boiler Model No.
REPAIR PARTS FOR USE WITH PROPANE GAS ONLY 3 6 4 5 6A 2 1 A98238 → Propane Gas Burners and Manifold Parts This is a Repair Parts List—Not a Packing List KEY NO. DESCRIPTION 1 2 3 4 5 6 6A 7 ‡ 24-v Gas Valve, Propane Gas Pilot Tube 10-32 X 3/16-in.
;;; ;;; ;; ; ;; ;; ; ;; ; ;;;;;;;; REPAIR PARTS 15 16 14 13 17 12 11 18 3 2 10 7 6 9 8 5 4 19 1 A95202 → Jacket—Section and Base Parts This is a Repair Parts List—Not a Packing List 7 8 9 10 11 12 13 14 Jacket, Right Side Panel Blower Cover Plate Rating Plate Jacket Tie Bar Boiler Base Base Side (2 Required) Base Insulation Base Front Base Rear Nipple, Boiler Jacket, Left Side Panel Jacket, Front Panel 1/4-in.
REPAIR PARTS → BOILER CONTROLS AND PIPING 1 3 2 7 5 4 6 10 11 9 8 A03109 KEY NO. 1 2 3 4 5 6 7 * 8 9 10 11 * * * * * * * * * * DESCRIPTION 3/4-in. ASME Relief Valve 3/4-in. X 5-1/2-in. Nipple Temperature-Pressure Gage—3-1/2-in. Shank 1-1/4-in. X 5-1/2-in. Nipple 1-1/4-in. X 3/4-in. X 1-1/4-in Tee L8148A Combination Hi Limit and Relay Control Taco 007 Circulator Grundfos UP15-42F Circulator 1-1/4-in.
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 is available, using popular video-based formats and materials. All include video and/or slides, plus companion book.
© 2003 CAC/BDP 7310 W. Morris St., Indianapolis, IN 46231 imbw3a06 —24— Catalog No.
