Check for physical damage to the tank, particularly rust and corrosion on the bottom of the tank. Check for water marks on the floor of the tank. Check for a leaking TPR valve and discharge pipe is installed. The covers at the electric heating elements should not be disturbed. Corrosion can be found where the water pipes are connected to the top of the tank. The electricity or the fuel may be shut off. There could be scorching at the burner cover area. The heat rollout shield should be in place. The draft hood and vent connector are often loosely attached. All tanks should be accessible with at least 24 inches of working space around them.

A water heater tank should be installed inside a pan in locations in a dwelling where a leak from the tank could cause damage to the structure or property. The pan is intended to catch water leaks from the tank or associated connections, or condensate from the tank. The pan should be made of galvanized steel or other material approved for that use. Pre-fabricated aluminum and plastic pans are common and widely used. Aluminum and plastic pans may not be allowed by every authority having jurisdiction (AHJ) or code official because they are not made of galvanized steel, and some tank manufacturers require the use of a metal pan only.

Hot water boilers should be provided with expansion tanks. There are two types of expansion tanks designated for use with a residential boiler system. A non-pressurized tank is simply a cylinder filled with air set at atmosphere pressure. A pressurized tank is a sealed cylinder divided by a flexible diaphragm. An expansion tank provides space for the water to expand as it is heated, and it keeps the water pressure within the normal operating range while the boiler is working. Thank you www.nachi.org

The following are 13 requirements for a discharge pipe serving a TPR valve:

Temperature and pressure-relief (TPR) valves are safety devices installed on water heating appliances, such as boilers and domestic water supply heaters. TPRs are designed to automatically release water in the event that pressure or temperature in the water tank exceeds safe levels.

Tankless coils are indirect water heaters that take their heat from the steam or hot water boiler that is used to heat the house. A cold-water supply pipe extends into the hottest part of the boiler water. The water in the copper tube is kept hot by the boiler water. When there is demand for hot water, water flows through the tube through the hot boiler water, and water is delivered to the fixture.

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Water circulating through a hot water circulation system becomes chemically inert and does not rust the piping. But water heaters have a constant supply of fresh water with lots of corrosion-causing oxygen. Because of this, water heaters are prone to corrosion. As a result, water heaters usually have an anti-corrosion rod or sacrificial rod installed. Sacrificial anodes are typically made of magnesium or aluminum. The rod is immersed inside the water heater tank, allowing the chemical reaction from the fresh water to attack it rather than the tank. In some areas, rods are replaced regularly.

If a laundry tub waste line connects to a clothes washer standpipe, the standpipe should be at least 30 inches above the standpipe trap weir and should extend above the flood level rim edge of the laundry tub. The outlet of the laundry tub must not be more than 30 inches horizontally away from the standpipe trap.

Whirlpool/jetted bathtub fixtures must be installed according to the manufacturer’s recommendations. The bathtub may be filled with water and tested during the rough-in plumbing inspection.