Features

If you’re like most people, chances are good that you don’t appreciate the convenience of hot water at the tap until there is none.  

This can be especially true when in the middle of a hot shower things turn cold, very cold. 

Generally, a water heater is one of the most reliable appliances in a home.  

With regular maintenance it can provide years of service. Besides keeping you in hot water (something we know a lot about), a good maintenance program can quiet a noisy water heater, lower your utility bill and extend the life of the water heater.  

And who can’t stand to save the cost and aggravation of yanking out a water heater and installing a new one that will do essentially the same thing that the old one did?  

It’s not like buying a fancy new appliance with lots of buttons and gadgets that will please and entertain you. A water heater is a water heater. 

It’s essentially a large thermos bottle that consists of an outer housing, a tank and a burner assembly.  

Have you ever wondered how your water heater does its job? Cold water enters at the top of the tank and flows through a plastic pipe called a dip tube, which delivers the cold water to the bottom of the tank where the burners are located.  

The heated water rises to the top of the tank where it flows out when needed. As hot water is drawn from the tank, more cold water enters the tank to be heated. The water is kept hot with a layer of insulation that is sandwiched between the tank and the outer housing. 

Corrosion presents the biggest threat to a water heat.  

The water’s chemistry combined with the high temperature creates a corrosive environment that can attack the tank, requiring its replacement.  

To prevent the tank from deteriorating, water heaters come equipped with an anode rod.  

The rod, also known as a sacrificial anode, is made of aluminum, zinc or magnesium. It attracts corrosive elements to keep the tank from deteriorating. The anode eventually will deteriorate completely – instead of the tank. 

To maintain this protection, the anode rod should be inspected at least once annually – more often where water is more corrosive. The anode rod can be inspected by removing a hex-head nut located at the top of the water heater.  

Once removed, the anode might consist of little more than a stub of wire – evidence that a new one is needed.  

Replacement anodes aren’t a standard stock item at many hardware stores or home centers, but can usually be found at a plumbing supply store. An anode will need to be replaced every five years or so. 

After the anode, sediment at the bottom of the tank is the next biggest threat to your water heater.  

Sediment reduces the efficiency of the burner, which raises your utility bill. Sediment also is a breeding ground for bacteria that can cause your hot water to smell like rotten eggs.  

And, as if that isn’t enough, sediment is usually the cause of the rumbling sound that makes a water heater sound like a locomotive. 

The most effective means of dealing with sediment is to get rid of it by regularly flushing the tank. This is done by connecting a garden hose to the drain valve located at the bottom of the tank, opening the valve and allowing water to flow for several minutes. 

Here’s a problem that might hit home. If during the first few minutes of a hot shower the water suddenly turns cold, you likely have a broken dip tube. That’s the plastic pipe that delivers cold water from the top of the tank to the bottom near the burners.  

A cracked or broken dip tube will cause cold water to mix with hot water at the top of the tank and, consequently, result in cold water at your shower or faucet. 

Ironically, your water heater is still flush with hot water.  

This can easily be solved by turning off the cold water supply to the heater, removing the water supply and nipple and broken dip tube and replacing it with a new one. 

Although generally reliable, a controller-thermostat will fail from time to time, causing the water temperature to vary erratically.  

The controller can be replaced without replacing the entire water heater – at a fraction of the cost. While the controller can be replaced by a do-it-yourselfer, this is something that you might want done by a pro.  

The safest and most energy-efficient setting for a thermostat is between 120 F and 130 F. A temperature setting less than 120 F could allow potentially fatal bacteria to propagate within the tank. A higher temperature setting can deliver scalding water. 

All water heaters have a temperature- and pressure-relief valve that is designed to prevent the water heater from exploding.  

Some manufacturers suggest testing the valve every six months or so by raising and lowering the test lever on the valve.  

This should produce a sudden burst of hot water from the drain line connected to the valve. More frequent testing can reduce the chance of a leak caused by mineral and corrosion buildup.  

However, if a leak results immediately after a test, simply operate the test lever several times to free lodged debris that might be preventing the valve from seating properly. 

Toxic gases produced by the burner should be safely vented through a flue pipe that attaches to the top of the water heater. Frequent inspections should be made to ensure that the flue pipe is aligned with the water heater exhaust port.  

Be sure that the flue is drawing properly by holding a match under the vent pipe. If the flame is drawn toward the vent pipe, it is drawing properly. If the flame blows away from the vent pipe, the flue is backdrafting, which could cause carbon monoxide poisoning.  

Check for an obstruction or damage to the vent pipe. If none exists, call in a pro to solve the problem. 

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