WATER HEATER FAQs 
 

1. What causes smelly water and what can be done about it?

There are many misconceptions in today's marketplace regarding the development and treatment of smelly water and the water heater. The most common odor complaint "rotten egg smell" is derived from hydrogen sulfide gas dissolved in the water. Concentrations as little as 1 ppm, can result in this odor.

"Smelly water" is a non-toxic water condition and can be present in municipal water supplies with large reserves and low flow. Most often "smelly water" will be noticed with well water or when a water heater has not been used for a long period of time (vacations, etc.) allowing the accumulation of this hydrogen sulfide gas and aggravating the odor problem. Active use of the water heater will reduce the problem.

The smell is an effect of four factors which must all be present for the odor to develop in a water heater. These factors include:

1. a high concentration of sulfate in the raw water
2. sulfate reducing bacteria, non-toxic to humans (sulfate is reduced to a sulfide state by the bacteria)
3. little or no dissolved oxygen in the water
4. hydrogen (a component of water. More of a gasification of the hydrogen may be present due to water conditions reacting with the anode).

With these factors the hydrogen and sulfur combine to form the hydrogen sulfide gas that gives off the rotten egg, smelly, odor to the water.

In each glass lined water heater there is installed at least one anode rod for corrosion protection of the tank. Smelly water can most easily be eliminated or reduced by replacing the anode(s) with one of less active material and then chlorinating the water heater tank and all hot water lines with a household bleach. STATE INDUSTRIES, INC. makes available an Anode Replacement Kit, part number 9000029, which includes chlorination instructions.

Utilizing the Anode Replacement Kit reduces hydrogen ions, but does not eliminate the sulfate reducing bacteria introduced into the water heater through the water supply, therefore "smelly water" can still be present. Chlorination of your water heater may help for a short time or for water heaters where the "smelly water" condition only occurs when the water heater has not been in use for a long period of time.

A long-term resolution may require chlorination of your well or water supply into the home. Contact your local water treatment professional for more information on chlorination of the water into your home.

Additional Information: Some water heaters are polymer lined. Polymer lined water heaters do not require an anode. In the case of "smelly water" (rotten egg odor) in a polymer lined heater, chlorination of your water heater may help if the condition is only present when the water heater has not been in use for a long period of time. The long-term solution most likely will require chlorination of your well or water supply into the home. Contact your local water treatment professional for more information on chlorination of the water into your home.

2. What causes water to drip or dump from a Temperature and Pressure Relief Valve (otherwise known as a T & P valve or Pop Off valve)?

The Temperature and Pressure relief valve is a safety device that is usually installed at the factory on water heaters. It is designed to open on a residential water heater, for your protection, when there is excessive water temperature or excessive water pressure in the water heater. There are many things that result in conditions causing a T & P to release water. Thermal Expansion in a closed system is a common cause that is often the last to be considered.

When water heats it expands, just as mercury in a thermometer expands rising up the scale to show you a persons body temperature. If the expansion of the mercury were to exceed the capacity of the thermometer the thermometer would explode. When water heats in a water heater it also expands. The expanding water will typically push back into the supply line preventing excessive pressure from building inside the water heater.

When a check valve (backflow prevention) or pressure reducing valve is installed (without a built in by pass) water is not allowed to push back into the supply line.

Where a backflow prevention device is installed, pressure, instead builds within the water heater. At 150 psi the T & P will begin releasing water to reduce the pressure within the water heater for your protection. When this occurs an expansion tank can be installed. An expansion tank helps by absorbing the excess water pressure in a diaphragm tank. The diaphragm allows for water to flow into the expansion tank as it is being heated and expanding and flow back into the water heater at other times. An expansion tank will prevent wasting water released from the T and P during expansion, as well.

Why would a backflow prevention/check valve be installed? To prevent water from your home from backing up into the main supply. Removal of the backflow prevention/check valve may not be an option, as it is likely required by codes in your area. Removal of a pressure reducing valve is also not a likely option, as controlling the water pressure into the home may be necessary.

Other causes of the T and P dripping or dumping water include:

• Sediment or lime deposits in the Valve. Replacement of the Valve may be necessary.
• Excessive water pressure. Installation of a pressure reducing valve with a built in by pass and reducing water pressure may be required.
• Excessive operation of a thermostat (typically due to points being fused together in a power surge or electrical storm). If the water is overheating in your water heater a thermostat may need to be replaced.
• A ground element. If the water is overheating in your water heater an element may be ground within its sheathing, typically due to a power surge of some type, and require replacing.
• Pressure surge from the operation of a solenoid valve. If the T & P only opens when operating the washing machine you may need to install a water hammer arrestor, shock absorber or blind cushion air pipe. An expansion tank may be the answer.

3. What are the popping, banging, rumbling or sizzling noises sometimes heard in water heaters?

The most common complaint of noisy water heater operation is the result of sediment accumulation in the water heater tank. Other causes are expansion and contractions of metal parts, condensation and water hammer.

An accumulation of sediment in the tank (even in small amounts) will create noises which begin shortly after the main burner ignites and the tank bottom heats up. The sound is usually described as popping, rumbling or boiling in the tank. Minerals in the water supply, which settle to the tank bottom after being heated form a hard layer of scale in which small air pockets form between the tank and the layer of sediment. As the minerals are continually heated the air pockets are released thus creating the noise.

Sediment is in all water supplies and there is no way to stop it from forming in the conventional water heater. Periodic flushing does help, but may not always eliminate the problem all together.

Expansion and contraction of some metal parts during periods of heat up and cool down is not uncommon and does not represent harmful or dangerous conditions.

Condensation may cause sizzling and popping noises within the burner area during heating periods.

Water hammer noises due to high water pressure in the home's plumbing system can result in leaking water heaters, banging water pipes and excessive wear on appliances. The water hammer or "surge" is caused by the bounced back or shock of highly pressurized water when a fixture or appliance is opened or closed quickly.

To avoid damage to the water heater we recommended one of the following:

1. Installing a pressure regulating valve upstream to your plumbing system that will maintain the outlet pressure to about 45 to 50 pounds per square inch.
2. Installing a properly expansion tank.

4. What should be considered when replacing an element?

The past has seen manufacturers use many different types of elements. The "LS" round flange and "TG" flat flange elements were once widely used. The most commonly used today is the "TR" or screw-in type. This element provides for easy installation and serviceability because it screws into a spud welded directly on the tank. "LS" or " TG" elements are bolted in.

Replacement elements should always be the same wattage and voltage as the original elements. Check the rating plate on the water heater to determine what wattage and voltage to choose.

When purchasing elements, you will notice that most elements have an alternate rating at different voltages. For example: a 240 volt 4500 watt element will have an alternate rating of 3800 or 3500 watts at 208 volts.

Always look for a stop sign on the water heater. If there is a stop sign with these words: "Genuine Amalloy 1-3/8" dia. Threaded Element" on the water heater, look for 1-3/8" threaded elements for replacement.

STATE INDUSTRIES, INC. Sandhog elements are designed for years of worry free service and to withstand even the worst water conditions. Request Sandhog elements when replacing the elements in your water heater.

5. What causes condensation, water dripping in the burner or on the floor around the water heater?

Many times gas fired water heaters are returned as leakers when the heater was not leaking, but rather condensation had formed. Condensation can most easily be defined as a reduction to a denser form (as from water to vapor). A perfect example of condensation is a glass of ice water on a hot day.

Whenever a water heater is filled with cold water, a certain amount of condensation will form while the burner is on. A water heater may appear to be leaking when in fact the water is condensation. This usually happens:

1. When a new water heater is filled with cold water for the first time.
2. When gas burns and water vapor is produced in water heaters, particularly high efficiency models where flue temperatures are lower.
3. When using large amounts of hot water in a short time and the refill water is very cold.

Moisture from the products of combustion condense on the cooler tank surfaces and form drops of water which may fall onto the burner or other hot surfaces to produce a "sizzling" or "frying" noise.

Excessive condensation can cause pilot outages due to water running down the flue tube onto the main burner and putting out the pilot.

Because of the suddenness and amount of water, condensation may be diagnosed as a "tank leak". After the water in the tank warms up (about 1 to 2 hours), the condition should disappear.

Do not assume the water heater is leaking until there has been enough time for the water in the tank to warm up.

An undersized water heater will cause more condensation. The water heater must be sized properly to meet the family's demands for hot water including dishwashers, washing machines, and shower heads.

Excessive condensation may be noticed during the winter and early spring months when incoming water temperatures are at their lowest.

Good venting is essential for a gas fired water heater to operate properly as well as to carry away products of combustion and water vapor.

So, before you pull that heater out, check it one more time and make sure it's not condensation your experiencing.

6. How is a water heater flushed?

Read all instructions provided here before proceeding as precautions must be taken to prevent scalding.  These instructions are provided as a guideline and are not the definitive answer for all makes and models.  Always consult the manufacturer instructions BEFORE attempting this procedure or better yet, have a D&D Plumbing Heating and Cooling professional perform this service.  This service is included for our UPP customers.

1. Turn OFF power to the water heater at the circuit breaker (electric) or main gas line (gas). WARNING: before removing any access panels or servicing the water heater, make sure the electrical supply to the water hearer is turned "OFF". Failure to do this could result in DEATH, SERIOUS BODILY INJURY, OR PROPERTY DAMAGE.
2. CLOSE the cold water inlet valve to the water heater.
3. OPEN a nearby hot water faucet and leave open to allow air in for draining.
4. CONNECT a hose to the drain valve and terminate to an adequate drain or outdoors.
5. OPEN the water heater drain valve to allow for tank draining. NOTE: If the water heater is going to be shut down and drained for an extended period, the drain valve should be left open with the hose connected allowing water to terminate to an adequate drain.
6. CLOSE the drain valve when the water stops draining and disconnect the hose.
7. The hot faucet should still be OPEN to allow the exit of air from the water heater. OPEN the shut off valve at the cold water inlet line. NOTE: The cold water supply valve must be left open when the water heater is in use. You will hear the heater start to fill.
8. To insure complete filling of the tank, allow air to exit by the nearby open hot water faucet. Allow water to run until a constant flow is obtained. This will let air out of the water heater and the piping. CAUTION: Never use the hot water heater unless it is completely full of water. To prevent damage to the tank and heating element, the tank must be filled with water. Water must flow from the hot water faucet before turning "ON" power.

7. What is FIRST HOUR RATING?

First Hour Rating is a calculated amount used to explain the performance abilities of a water heater within the first hour of use when recovered to the thermostat setting. In other words, when determining the first hour rating you will start with a fully heated tank of water.

Approximate first hour rating can be determined with the following formula:

TANK CAPACITY x .70 + RECOVERY = FIRST HOUR RATING.
EXAMPLE: The water heater is 40 gallons, elements are 5500 watts (electric water heater) 40(gallons) x .7(70 percent of the tank capacity) + 22.5(GPH at 80 degree rise in temp) = 50.5 gallons first hour rating.

Why multiply by 0.70? The amount of water in the tank is multiplied by 70 percent because as water is being used, new cold water is entering the tank and diluting some of the heated water.

The thermostat senses the cold water introduced into the tank and begins the heating process again.

Use the following guide as a quick reference in determining 70% of the tank capacity: If your tank capacity is:

8. What is RECOVERY RATE?

Recovery rate is the amount of hot water the water heater is capable of providing in a given period of time, not to be confused with first hour rating, which includes recovery rate plus 70 percent of the tank capacity (see FAQ #7). The amount of hot water provided will depend on several things. Wattage of a heating element in an electric water heater, temperature rise and the time frame for which you are measuring the recovery rate. The charts below are based on gallons per hour (GPH).

For example: in an electric water heater if the wattage of the elements is 4500, the incoming water temperature is 40 degrees and you are heating the water to 120 degrees (temperature rise of 80 degrees) the recovery rate is 23.0 GPH.

9. What is a Dry-Fired element?

Heating elements are designed to operate in water. An element is Dry-Fired when power is applied to the element with inadequate or no water in the water heater. Dry-Firing an element raises the temperature on copper elements to a destructive point.

The expected life of a dry-fired copper element will be reduced to a point that it may fail completely in 30 to 45 seconds, or it may last several months and fail at that point. Operating in water, the tubing temperature of the element will not exceed the temperature of the water by more than 2 degrees F.; however in a dry tank the tubing temperatures may reach 1900 to 2000 degrees F.

Dry-fired elements can be recognized in three ways:

1. The zinc plating will have melted or completely burned off, leaving exposed copper.
2. The tubing of the element will be completely annealed (soft) to a point that it can be easily bent in the straight sections of the tube.
3. The terminal block may show signs of melting at the base next to the screw plug.

Note: Only number 3 would be evident on STATE INDUSTRIES, INC. Sandhog Elements.