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Service handbook
commercial gaS W aTer hea TerS
for modelS: bcl
381T1206noX, 381T1546noX, 395T1806noX,
395T1996noX, 395T2506noX
ul Tra loW nox SerieS 104
PO Box 1597, 500 Princeton Road
inSTalla Tion conSidera TionS - pre Service checKS -
Johnson City, TN 37605
conSTrucTion - opera Tion & Service - TroubleShooTing
Servicing Should only be performed by a Qualified Service Technician
PRINTED IN THE U.S.A. 0113 325257-000
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Table of conTenTS INTRODUCTION ...................................................................... 2 QUAlIfICATIONS ..................................................................... 2 TOOlS REQUIRED .................................................................... 3 INSTAllATION CONSIDERATIONS ....................................................... 4 GAS AND ElECTRICAl CHARACTERISTICS ............................................... 4 GAS PRESSURE – REQUIREMENTS ........................
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inTroducTion The service handbook is designed to aid in servicing and troubleshooting American Water Heaters BCl commercial water heaters in the field. No duplication or reproduction of this book may be made without the express written authorization of American Water Heaters. The following text and illustrations will provide you with a step by step procedure to verify proper installation, operation, and troubleshooting procedures. Additional quick reference data is included to assist you in
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ToolS reQuired • Electrical multimeter capable of measuring continuity/ ohms, ac & dc volts, amperes, microamperes, millivolts, and frequency (hz) • UEi Model Dl289 or equivalent • Digital manometer + 60" w. c., resolution 0.01" increments note: A digital manometer is required for testing pressure switches and can replace a gas pressure gauge, draft gauge or slack tube manometer for checking gas pressure. • UEi model EM200 or equivalent • Water pressure gauge w/lazy hand and hose bibb connec
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inSTalla Tion conSidera TionS gaS and elecTrical characTeriSTicS gaS Supply preSSure modelS gaS Type vol TS/hZ ampereS minimum maXimum all models Natural 3.5" WC (0.87 kPa) 14.0" WC (3.48 kPa) 120/60 < 5 All models require a minimum gas supply pressure of 3.5” W.C. The minimum supply pressure is measured while gas is flowing (dynamic pressure). The supply pressure (dynamic) should never fall below 3.5” W.C. The supply pressure should be measured with all gas fired appliances connected to the c
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air Supply : Stoichiometric or theoretical complete combustion requires 10 cubic feet of air per 1,000 BTU of gas supplied. The National fuel Gas Code also recommends an additional 2.5 cubic feet of “excess” air. for information on minimum make-up air opening sizes for various building installations, refer to the National fuel Gas Code NfPA 54/ANSI Z223.1. inSufficienT maKe-up air, nega Tive air preSSure and doWndrafTS: Downdraft Caused by kitchen Vent Hood A lack of combustion and ventilatio
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maKe-up air – direcT communica Tion WiTh ouTdoorS: A fresh supply of make-up air for combustion can be supplied to the water heater through make-up air ducts, which directly communicate with the outdoors. (Not Direct Vent.) Two openings are required: one within 12 inches (30 cm) of the top of the enclosure and one within 12 inches (30 cm) of the bottom of the enclosure. Each opening must have a free area of not less than 1 square inch per 4,000 BTU/Hr of the total input of all appliances wit
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air reQuiremenTS: for safe operation an adequate supply of fresh uncontaminated air for combustion and ventilation must be provided. An insufficient supply of air can cause recirculation of combustion products resulting in contamination that may be hazardous to life. Such a condition often will result in a yellow, luminous burner flame, causing sooting of the combustion chamber, burners and flue tubes and creates a risk of asphyxiation. Do not install the water heater in a confined space unle
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fea TureS and componenTS Exhaust/Vent Inlet Tube Outlet Tube T & P Relief Valve Upper Thermostat Probe/ECO The Eliminator Clean Out Cover lower Thermostat Probe Drain Valve Control Box Assembly Gas Gas Control Control Valve Valve 8 Servicing should only be performed by a Qualified Service Technician
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bloWer and burner aSSembly Blower Silicone flange Blower Gasket Burner Gasket flange Plate Gas Control Valve Brass locknuts (3) flame Burner Sensor Spark Igniter Skirt Ring flange Gasket burner replacemenT: 1. Turn off the gas supply and electricity to the water heater and remove the blower cover. 2. Disconnect the spark ignition cable and ground wire plus the flame sensor wire at their connection points on the flange plate. 3. Disconnect the hose tubes, power supply and PWM (Pulse-Width
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8. Support the blower and burner assembly in a vertical position with the burner extending downward. 9. Remove the 3 brass locknuts holding the blower adapter to the flange plate. 10. Separate the blower from the flange plate. 11. Clean the flange plate surfaces removing any portions of the old burner gasket. 12. Remove the burner from the flange plate. 13. Insert the new burner into the flange plate and align the notch in the burner flange with the tab in the flange plate. 14. Install the new
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SparK igniTer, flame SenSor, SighT glaSS The spark igniter and the flame sense rod are shown below. Also shown is the burner sight glass. These features are typical for all models. Sightglass Burner flame Sensor Spark Igniter SparK igniTer / flame SenSor / conTrol Timing SparK igniTer This water heater is equipped with a spark igniter. Do not damage the ceramic insulator. Inspect the igniter ceramic insulator for any cracks. The spark gap between the spark rod and grounding rod is 1/8". flame
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venTing inSTalla Tion – venTing ca Tegory and ma TerialS bcl venTing category i • Non-condensing, negative pressure in vent, below atmospheric. Type venting • Must be installed Conventional Vent; uses room air for combustion and discharges flue gases to the outdoor atmosphere through one pipe. vent materials • B Vent. minimum clearanceS This water heater is approved for installation on combustible flooring in an alcove with minimum clearance from combustion construction as indicated in below f
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eXTerior clearanceS The illustration below shows the required clearances for venting units using natural draft venting. The vent must extend at least 3 feet above the highest point where it passes through a roof of a building and at least 2 feet higher than any portion of a building within a horizontal distance of 10 feet (for vents of 12 inches in diameter or less). 13 Servicing should only be performed by a Qualified Service Technician
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venTing T ableS – Technical venTing da Ta Type b gaS venT multiple gas fired Tank-Type heaters When venting multiple tank type heaters using Type B vent pipe, follow the installation diagram and tables below which give sizing and data based upon NfPA 54 ANSI Z223.1. model bcl381T1206noX input: 120,000 btu/hr Total vent height (feet) vent connector size: 6 inches 6 8 10 15 20 30 50 100 input btu/hr rise vent connector diameter (inches) 120,000 1 ft. 6 6 5 5 5 5 5 5 120,000 2 ft. 5 5 5 5 5 5
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opera Tion and Service SeQuence of opera Tion: 1. Switch power on to unit. 2. Thermostat calls for heat. 3. UGB (Universal Gas Board) sends PWM signal to blower to start the blower. 4. Blower runs at high prepurge speed for 20 seconds. 5. Combustion Blower initiates air flow through water heater closing the Prover Switch. 6. After 30 seconds, the Ignition Control provides power to the Spark Igniter and Gas Valve. 7. Ignition Control maintains spark for up to 4 seconds and monitors flame Sensor t
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SeQuence of opera Tion – floW charT Switch power on to unit Thermostat calls for heat UGB sends PWM signal to Blower to start the blower at high purge speed Blower engages Prover Switch 20 seconds later blower Aer 30 seconds, Ignion Control provides power to Spark Igniter and opens Gas Valve Ignion Control maintains spark for up to 4 seconds and monitors Flame Sensor to determine if Burner is lit NO Wait 15 minutes. NO YES Does Burner Is this the third Gas Valve– off Blower runs at
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lighTing and opera Ting label FOR YOUR SAFETY READ BEFORE OPERATING If you do not follow these instructions exactly, a fire or WARNING: explosion may result causing property damage, personal injury or loss of life. FLAMMABLE BEFORE OPERATING: ENTIRE SYSTEM MUST BE FILLED WITH WATER AND AIR PURGED FROM ALL LINES. If you cannot reach your gas supplier, call the fire A. This appliance does not have a pilot. It is equipped with department. an ignition device which automatically lights the burner.
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TroubleShooTing remedy complainT cauSe uSer Qualified agency *Water not hot enough. Thermostat set too low. Set thermostat dial to a higher temperature Upper and/or lower Call qualified agency. Check continuity and resistance temperature probe out of (Ohms) of upper and lower calibration. temperature probes. Replace probes if out of specification. *Insufficient hot water. Thermostat set too low. Set thermostat dial to a higher temperature *See WATER TEMPERATURE Upper and/or lower Call qual