A.O. Smith BTF-75 High Temperature CUT-OFF Switch, Venting System, Power Venter Maintenance

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HIGH TEMPERATURE CUT-OFF SWITCH

The thermostat has a built-in temperature cut-off switch (TCO), which will shut off gas to the burner in case of excessive water temperature. If the TCO functions the valve will flash 4 times and the valve must be replaced. It is important that a serviceman be called to determine the reason for limit operation and thus avoid repeated thermostat resetting. Lower the temperature adjustment dial setting on control.

VENTING SYSTEM

HAVE VENTING SYSTEM CHECKED EVERY SIX MONTHS FOR OBSTRUCTIONSAND/ORDETERIORATIONINVENTPIPING.

A.Insofar as is practical, close all doors, windows and air inlets to the building. Turn on all exhaust fans (range hood, bathroom exhaust, etc.) so they will operate at their maximum speed. Close fireplace dampers.

B.Turn water temperature adjusting knob to full, counterclockwise and open water faucet if necessary to keep burner in operation.

C.“CHECKING THE DRAFT.” Operate the water heater for several minutes and check to see if it is venting properly by passing a lit match or paper near the opening of the Air Supply Box. If the draft is proper, the match flame will be drawn into the Air Supply Box (fig 11). If not, the combustion products will tend to extinguish the flame. If an improper draft exists, do not operate the water heater until proper adjustments or repairs are made to provide adequate draft through the gas vent.

D.Next, turn on all other fuel burning appliances within the same room so they will operate at their full input.

Repeat step C above.

FIGURE11

POWER VENTER MAINTENANCE

The BTF-75 must be inspected quarterly. Points of inspection are:

1.MOTOR - Motor must rotate freely. This is a sealed motor and no oiling is required.

2.WHEEL - Wheel must be clean of soot, ash or any other coating which inhibits either rotation or air flow. Remove all foreign material from vent system before operating.

3.AIR SUPPLY BOX-Every month check operation and make sure nothing is blocking dilution air entrance.

4.The pressure switch part inside the power venter must be open and free from deposits of soot, carbon, etc.

For safety and satisfactory operation it is recommended that the heater be checked once a year by a competent service person.

T & P VALVE

At least once a year, the temperature and pressure relief valve must be checked to ensure that it is in operating condition. Lift the lever at the top of the valve several times until the valve seats properly and operates freely.

WARNING

THE WATER PASSING OUT OF THE VALVE DURING THIS CHECKING OPERATION MAY BE EXTREMELY HOT. AVOID CONTACT AND DISCHARGE SAFELY TOPREVENT WATER DAMAGE.

DRAINING

Periodically open the drain valve and allow the water to run until it flows clean. This will help prevent sediment build-up in the tank.

It is normal for lime and scale deposits to form within the tank and on the heat exchanger surfaces. Such deposits will not be removed by periodic draining. It is necessary to chemically delime the affected parts in water areas where such deposits are encountered. Contact your dealer or plumber for deliming information.

If the heater is to be shut off and exposed to freezing temperatures, it must be drained. Water, if left in the tank and allowed to freeze, will damage the heater.

Turn off the gas and cold water inlet valve to the heater.

Open a nearby hot water faucet and the heater drain valve.

BE CAREFUL TO GRASP THE DRAIN VALVE HANDLE SO THAT THE HAND IS NOT EXPOSED TO HOT WATER. IF DESIRED, A HOSE MAY

BE CONNECTED TO THE DRAIN VALVE TO CARRY THE WATER AWAY.

WARNING: The water CAN BE HOT.

The drain valve must be left open during the shutdown period.

• To restart heater, refer to the instructions under OPERATION.

MAIN BURNER AND IGNITER

Check main burner (figure 12) at least every 6 months for proper flame characteristics. The main burner should display the following characteristics:

1.Provide complete combustion of gas.

2.Cause rapid ignition and carryover of flame across entire burner.

3.Give reasonably quiet operation during ignition, burning and extinction.

4.Cause no excessive lifting of flames from burner ports.

If preceding burner characteristics are not evident, check for accumulation of lint or other foreign material that restricts or blocks the air openings to the heater or burner.

WARNING

SOOTBUILD-UPINDICATESAPROBLEMTHATREQUIRESCORRECTION BEFORE FURTHER USE. CONSULT WITH A QUALIFIED SERVICE TECHNICIAN.

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Contents SmartValve is a Registered Trademark of Honeywell Inc Commercial GAS, GLASS-LINED, TANK-TYPE Water HeaterForeword ROUGH-IN-DIMENSIONSALL Dimensions in Inches Recovery CapacitiesGeneral Safety Information Table of ContentsInstallation Water Connections AIR RequirementsUnconfined Space Confined SpaceVent Pipe Termination Single TemperatureClosed Water System Venting Relief ValveNumber Maximum Elbows Pipe Feet If using 3 inch vent pipeIf using 4 inch vent pipe Planning the Vent SystemInstallation of Sidewall Vent System Vent Terminal INSTALLATION, SidewallPreparation of Blower Assembly Power Vent Wiring Schematic Figure Initial Preparation Installation of Vent SYSTEM, SidewallInstallation of Vertical Vent System Vent Pipe PreparationStep a PrimerCement Making the JointTo Operate the Heater OperationGAS Connections Connection of GAS PipeDo not TRY to Light the Burner by Hand WatertemperatureadjustmentDo not TRY to Light the Burner by Hand What to do if YOU Smell GASPurging MaintenanceTemperature Regulation Water Temperature Adjusting DialValve High Temperature CUT-OFF SwitchPower Venter Maintenance Venting SystemCathodic PROTECTION-ANODE Service and RepairTrouble Shooting CondensationYellow Flame TroubleshootingVent Pipe TOO HOT Above 170 FTroubleshooting with the LED OFFFlash Replace HSI Check for Proper Voltage ATYES Turn on GAS Supply PlugALL Other Parts Service and Repair ExpensesClaim Procedure Tank