POWERED ANODE SYSTEM

To insure a long, trouble-free operating life, BTH 300, 400 and 500 are factory equipped with a powered anode system. The anodes are of a permanent design and do not need replacing unless damaged.

DRAIN VALVE AND ACCESS PANELS

The heaters are equipped with a 3/4" drain valve.

An access panel covers the cleanout opening in the tank which is sealed by a gasket and cover, see Figure 24.

RELIEF VALVE

At least twice a year, the temperature and pressure relief valve should be checked to ensure that it is in operating condition. To check the relief valve, lift the lever at the end of the valve several times. The valve should seat properly and operate freely.

If water does not flow, remove and inspect for obstructions or corrosion. Replace with a new valve of the recommended size as necessary. Inspection of the valve should be performed at least every three years. 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 often than every three years.

CAUTION

BEFORE MANUALLY OPERATING THE VALVE, MAKE SURE THAT A DRAIN LINE HAS BEEN ATTACHED TO THE VALVE TO DIRECT THE DISCHARGE TO AN OPEN DRAIN. FAILURE TO TAKE THIS PRECAUTION COULD MEAN CONTACT WITH EXTREMELY HOT WATER PASSING OUT THE VALVE DURING THIS CHECKING OPERATION.

If the temperature and pressure relief valve on the heater discharges periodically or continuously, it may be due to thermal expansion of water in a closed water supply system, or, it may be due to a faulty relief valve.

Thermal expansion is the normal response of water when it is heated. In a closed system, thermal expansion will cause the system pressure to build until the relief valve actuation pressure is equaled. Then, the relief valve will open, allowing some water to escape, slightly lowering the pressure.

Contact your water supplier or local plumbing inspector on how to control this situation.

Two common corrections are listed in the Checklist and Service Information which appears later in this manual.

ABOVEALL, DO NOT PLUG THE TEMPERATUREAND PRESSURE RELIEF VALVE. THIS IS NOT A SOLUTION AND CAN CREATE A HAZARDOUS SITUATION.

VENT SYSTEM

Examine the vent system every 3 months. Points of inspection are as follows:

1.Check for obstructions and/or deterioration of vent piping and vent hood. Replace immediately where needed.

2.Vent pipe and vent hood screen should be cleaned of foreign material and soot. The screen is located inside the vent hood outlet and is accessible from the outside of the hood. Do not reach inside the vent hood when the heater is in operation.

3.Check all vent system connections for leakage and reseal as required using Hi Temp Silicone sealer or equivalent.

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A.O. Smith 300A, 500A warranty Powered Anode System, Drain Valve and Access Panels, Vent System