Water Heater FAQ

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How do I know when to replace my water heater? If your water heater is 8 years old, or older then chances are the time is near for a new water heater. typical signs of a faulty water heater include leaking from the water heater unit, and quickly running out of hot water. If you only have enough hot water for a single shower in the morning, that is a bad sign. Corrosion on the outside of the unit is another warning sign.

What is the popping sound coming from the water heater? This is most commonly found in gas water heaters, although it can be in electric units as well. This sound is the accumulation of sediment and scales in the bottom of the water heater. When heated, they create a popping sound.

Is it safe to flush my water heater? When your heater is over 8 years old, it is not recommended to make any repairs or preventative maintenance such as a water heater flush. The main reason is because after so many years of accumulated corrosion and scale build up, when you disrupt the constant pressure inside the tank, you very well could create a leak on the inner tank which is not repairable. Most manufacturers recommends multiple flushes per year from installation.

How long does a water heater last? According to consumer reports, the easy answer is 8-12 years, although the number can fluctuate greatly depending on the brand of the water heater, and the quality of your water.

Does water quality make a difference to the life of my water heater? Absolutely. Chlorine in your water increases the corrosion in your system, which can lead to your water heater failing before its normal lifespan. For more information on water quality, visit www.waterfiltrationexperts.com.

What size water heater is the right size for my home? It depends on the number of people in your household and the number of baths/showers and dish washing machines you run. Add the number of people in your household,  the number of showers & the washing machines you have and use the formula below to determine the size unit you need.

Gas Water Heaters

• 4 or less – 30 Gallon capacity heater
• 5-7 – 40 Gallon
• 8-9 – 50 Gallon
• 10-12 – 75 Gallon

Electric Water Heaters

• 4 or less – 40 Gallon
• 5-6 – 50 Gallon
• 7-8 – 66 Gallon
• 9-10 – 80 Gallon
• 11-12 – 120 Gallon

Is a gas water heater or an electric water heater more efficient? Gas is, by far more efficient. The operation cost of electric units is 30% to 50% higher than operational cost of gas water heaters.

What is BTU? BTU stands for British Thermal Unit and is the unit of measure for the heat required to raise one pound of water one degree Fahrenheit.

How do I find out what BTU my gas water heater is? This should be on a small plate attached to your water heater. This is not the big yellow energy efficient decal on the side, but a small metal plate that will include your serial number.

When you talk about water heaters what does Thermal Efficiency mean? Without getting too technical, thermal efficiency directly relates to how effectively the heat from the energy source is transferred into the water in combination with the operational and stand-by loss of heat from the water. The higher the efficiency rating, the lower the operational cost of the water heater.

Is a tankless water heater worth the investment? A tankless system can typically cost you 2-3 times more than a normal water heater, but when installed and maintained correctly,  it is definitely a cost benefit.


• Space savings
• Peace of mind (no more flood hazard with a water tank)
• Life expectancy 2 to 3 times longer than a tanked water (20-30 years)
• Operational cost savings
• Never ending supply of hot water
• Environmentally friendly (1/10 carbon output/greenhouse gases than a tank type water heater).


• Upfront cost is 2-3 times higher than a normal storage tank when properly installed by a certified installer
• When power goes out there is no hot water (battery backups are available)
• When not installed 100% correctly it will never perform like it should and you will be displeased with the performance.

I have brown rusty water coming from the hot water tap, what is the problem? This could be an indication of bacteria in your system or an anode rod could have failed. It is likely that your water heater needs to be replaced.

I drained water from my water heater and this white stuff came out, what is it? Chances are what you are seeing is a buildup of sediments or deposits of calcium and magnesium salts. If too much of this sediment adheres to the bottom of your tank it will eventually need to be replaced. The buildup will rob you of hot water and make the unit less energy efficient.

What is the best brand of tank type water heater? State, A.O. Smith and Rheem are the top rated brands by licensed plumbers used in the field daily for both gas and electric tank type water heaters.

What is the best brand of tankless water heater? After 10 years plus of data and dozens of licensed contractors across the United States, our belief is that Rinnai is the number one tankless water brand with Noritz being second. This is based on several factors including performance, reliability, manufacturer customer service, local installer service support network, and technology.

How much does it cost to run my water heater? A typical 50 gallon gas water heater that is 10 years old can cost you between $20 and $30 a month to run. A typical 50 gallon electric water heater that is 10 years old can cost you between $40 to $50 a month to run.These numbers are averages based on 3-4 occupants and moderate usage.

Why do we run out of hot water in the mornings before everyone has had a shower? This is typically a sign that your water heater is too small for the household, or slow to recover. This is when you should consider a tankless water heater.

Do you need a permit to replace your water heater? In North Carolina, the general statute requires a licensed plumbing contractor to perform a water heater change-out. As long as the energy source, size, and location are the exact same a permit and inspection are not required. (North Carolina only.) General statute also requires that everything is brought up to current code when installation occurs.