be called to determine the reason for limit operation and thus avoid repeated thermostat replacement. Lower the temperature adjustment dial setting on the new control.

VENTING

HAVE VENTING SYSTEM CHECKED EVERY SIX MONTHS FOR OBSTRUCTIONS AND/OR DETERIORATION IN VENT PIPING.

TEMPERATURE & PRESSURE RELIEF VALVE

At least once a year, the temperature and pressure relief valve, fig. 1. 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.

If water does not flow, remove the valve and inspect for obstructions or corrosion. Have a qualified servicer replace with a new valve of the recommended size as necessary. Do not attempt to repair the valve, as this could result in improper operation and a tank explosion. In areas with poor water conditions, it may be necessary to inspect the T&P valve more frequently.

WARNING

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

DRAINING

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, fig. 1.

•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.

DANGER

The water CAN BE HOT.

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

•To restart heater, refer to the FILLING instructions under

OPERATION.

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. 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.

CONDENSATION

Combustion products contain water vapor which can condense on the cooler surfaces of the tank forming droplets which drip into the fire or run out on the floor. This is common at the time of startup, after installation, during periods of time when incoming water is very cold, or the heater may be undersized for the requirements.

Occasional or steady water leakage from the bottom of the flue may be caused by corrosive combustion products or an improper vent. Check with your dealer for more information.

CATHODIC PROTECTION - ANODE

The anode rod within the tank is designed to be slowly consumed cathodically, minimizing corrosion in the glass- lined tank. A hydrogen sulfide (rotten egg) odor may result if water contains high sulfate and/or minerals. Chlorinating the water supply should minimize the problem. (See EXTENDED NON-USE PERIODS).

NOTE: Anode must remain installed (except for inspection) to avoid shortening tank life. See LIMITED WARRANTY. Replace as necessary.

ANODE ROD MAINTENANCE

The anode rod is used to protect the tank from corrosion. Most hot water tanks are equipped with an anode rod. The submerged rod sacrifices itself to protect the tank. Instead of corroding the tank, water ions attack and eat away the anode rod. This does not affect the water’s taste or color. The rod must be maintained to keep the tank in operating condition.

Anode deterioration depends on water conductivity, not necessarily water condition. A corroded or pitted anode rod indicates high water conductivity and should be checked and/ or replaced more often than an anode rod that appears to be intact. Replacement of a depleted anode rod can extend the life of your water heater. Inspection should be conducted by a qualified technician, and at a minimum should be checked annually after the warranty period.

CAUTION

Before removing the anode: 1) the tank water should be cool, 2) the cold water shut off valve must be closed, and 3) water pressure must be relieved by opening a nearby faucet.

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A.O. Smith FDVT, SDV owner manual Temperature & Pressure Relief Valve, Draining, Condensation, Cathodic Protection Anode
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SDV, FDVT, FDV specifications

A.O. Smith is a leading name in the water heating industry, known for its innovative products and commitment to quality. Among its extensive lineup, the FDV, FDVT, and SDV series stand out due to their advanced features and technologies designed to enhance performance and efficiency.

The FDV series represents a revolution in traditional water heating solutions. These direct vent water heaters are designed to provide hot water on demand while minimizing energy consumption. The FDV models utilize a dual venting system, allowing for the efficient expulsion of combustion gases outside the home while drawing in fresh air for the combustion process. This design increases efficiency by ensuring optimal combustion and improves safety by reducing the risk of indoor air contamination.

The FDVT series builds upon the innovative features of the FDV, integrating a tankless design that provides unlimited hot water. This makes it an ideal choice for households with higher hot water demands. The FDVT models use high-efficiency burners and advanced heat exchangers to deliver hot water quickly and consistently, adapting to varying flow rates. They are also equipped with intelligent control systems that monitor water usage patterns and adjust operation accordingly, optimizing energy efficiency without sacrificing performance.

The SDV series caters to those looking for a reliable and efficient storage tank water heater. With a robust construction and reliable design, these water heaters are built to last. The SDV models are designed with high-quality insulation to minimize heat loss, making them energy-efficient options for storing hot water. Additional features include built-in safety mechanisms, such as temperature and pressure relief valves, ensuring safe operation at all times.

A.O. Smith's commitment to innovation is evident in their use of cutting-edge technologies across these series. Both the FDV and FDVT models incorporate sophisticated electronic controls, enabling features like scheduling and remote access for greater convenience. They are compatible with smart home systems, allowing users to monitor and manage water heating remotely.

In terms of energy efficiency, models within these series are designed to exceed industry standards, often qualifying for energy rebates and incentives in various regions. With features such as modulating burners, they adjust the energy input based on demand, significantly reducing operational costs.

Overall, A.O. Smith's FDV, FDVT, and SDV series represent leading-edge solutions in water heating, combining efficiency, safety, and advanced technology to meet the diverse needs of modern households. Whether seeking endless hot water or reliable storage solutions, these series offer unparalleled options that prioritize performance and sustainability.
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