Hot Water Heater FAQS

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Hot Water Heater FAQ’S

If you are having water heater problems, Water Heaters Only, Inc. FAQ is here to help you with the most common hot water heater questions. These water heater answers come from some of the most frequently asked water heater questions that our team of experts have encountered in our 55 years of service. If you need immediate assistance with your water heater, please call us 24 hours a day, 7 days a week, 365 days a year. We are the professional water heater service and installation company ready to fix your water heater problems!

Our Top 5 Most Frequently Asked Water Heater Questions

I have no hot water and why won’t my pilot light?
Why is there a water leak under my water heater?
Why do I not get enough hot water or as much hot water as I used to?
Why does my water heater make a “rumbling” noise?
Are tankless or “on demand” water heaters a good alternative?

This page provides more information about tankless water heaters. Some of the features include a constant supply of hot water with 82% to 95% energy efficiency, water heating on demand and no tank to worry about leaking. Tankless water heaters are space savers that offer remote control options and often last longer than traditional hot water heaters.

More Frequently Asked Water Heater Questions

Why is the pipe on the side of my water heater ‘leaking?’

Most likely you are referring to the overflow pipe attached to the temperature relief valve on the water heater. This is a safety valve and helps relieve excess temperature and pressure inside the water heater in case of high pressure or an overheated water heater. Occasionally this pipe will “blow off a little steam” and there will be no problem with your water heater, but if it leaks frequently or continuously, there may be a problem. Call and speak with one of our water heater experts and they can help determine if you have a problem.

What type of water heater do I have?

You can start with looking up the model number, but those may vary and lead to confusion. If it doesn’t bring you the right results, look at the visuals of your water heater. A gas water heater will have a pipe going into the bottom to feed it gas. A tankless water heater will be smaller, square, and mounted on the wall. There are plenty of elements to decipher, and we want you to be sure. If you call, we can help you confirm what type of water heater you have, or check our products page.

Why does it take so long to get hot water at my tap or shower? How can I get it faster at my kitchen or bathroom?

Waiting a long time at the faucet for hot water to arrive is usually due to the plumbing in the home. When the hot water leaves the tank of the water heater it has to travel through the piping to reach the faucet. If you have a ranch style home or a large home sometimes these “plumbing runs” can be long and it takes a while for the hot water to arrive. Re-circulation pump systems are a good solution to this problem. back to top

Another good option can be a tankless water heater, installed at the point-of-use, such as under a bathroom cabinet at the far end of your home. Hot water is nearly immediate with a tankless water heater. Although they cost more up front than traditional tank water heaters, the energy efficiency and water savings can be substantial over time.

Call and speak with one of our water heater experts to get more information on a re-circulation system or tankless water heater that would work for your home. back to top

I need to shut off my water heater, can you tell me how to turn off a leaking water heater?

Emergency Shutdown Instructions: Call us at (866) 946-7842 to speak with a hot water heater expert, 24 hours a day, 7 days a week, for help shutting down your water heater.

You can go here for a video to walk you through turning off your water heater. back to top

There is a valve that releases, drips or ‘spits’ water on occasion, is that normal?

Yes, but….

This is your pressure and temperature relief valve (PRV). It is typically set at 150lbs pressure or 210-degree Fahrenheit. The valve is working normally if puts out a little water when the temperature is too high, in order to release pressure, creating a safer situation. This is a safety feature required on all tank water heaters and all of them do this on occasion.

If there is constant dripping, flooding or a ‘whistling noise’, you will need to have a professional check your relief valve for failure. It can be dangerous to have the pressure build up, and it should be checked right away. A water heater that continues to overheat is also at serious risk of failure. Call us right away if your think there is too much pressure or your hot water heater is overheating and we will help you with your concerns. back to top

At times I hear noises like ‘water dripping into a hot skillet’ coming from my water heater; do I have a problem?

A gas water heater uses approximately 10 parts of air for every part of gas to create complete combustion and with that air comes moisture. That moisture can be put into droplets as it condensates going up a cold “chimney”. In short, that sizzling noise is normal at those times when you put high demand on your water heater and particularly when the heater is in a cold environment or on a brand-new heater just fired up with a full tank of cold water. If you hear dripping constantly or see a puddle under the water heater, that could be the sign of a problem, give us a call and we can try to help determine that with you. back to top

How long does a water heater take to fully heat up?

Generally, hot water heaters take about 45 minutes to be fully hot. If your water heater has been turned off or if you have just had a new unit installed it will take approximately 45 minutes to heat the water up. Each water heater varies in recovery depending on the gallon capacity and BTU input, but if after about 1 hour there is still no hot water then the unit is not working properly. Gas water heaters recover quicker than electric water heaters, but either way you should not have to wait more than about 1 hour for a water heater to fully heat and produce hot water. back to top

Are drain pans under a water heater recommended?

In some locations sheet metal pans are required and in other situations they are highly recommended. You can guess the situations where water leakage could do the most damage. Water heaters located in interior closets or attics can become a nightmare. Too often we hear of a slow leak from either a pressure and temperature relief valve “popping off” or a tank failure going completely undetected until the day when someone notices hardwood flooring starting to buckle in the dining or bedroom adjacent to the small closet with the water heater. We suggest thinking twice before going without a pan drained to a safe place outside the home. back to top

How soon can you get to our home/business?

Most often, we are at the job site within a few hours of your initial phone call for service. Of course, we can also schedule to be there at just about any time that works for you. Our technicians leave our warehouses fully loaded with the most common sizes of water heaters and most every conceivable part necessary, as they travel from job to job, ensuring we can get your hot water heater operating again as quickly as possible. Call us 24/7/365 for service. back to top

What are ways to conserve on hot water heating?

  • Lower water heater’s preset temperature setting-Typically preset from the manufacturer at 140 degrees, you can lower the thermostat to 120 degrees and still have comfortably hot showers. In the summertime or while on extended vacation, a setting of 110 degrees can save you money and lower your energy costs.
  • Replace shower heads with low flow heads. Many shower heads today come with plenty of pressure and less water usage, and you will get a long, hot shower that saves on water and money going down the drain.
  • Sediment flush – Some locations are notorious for mineral-rich, sedimentary water, and in these areas, flushing the water heater can extend its life and save on energy costs. Once sediment is allowed to build up and solidify it can be almost impossible to remove from residential model water heaters. The sediment is similar to coral, and makes your water heater work harder. To prevent this solidification a homeowner can flush the heater periodically, typically once a year.
  • Inspect regularly for leaks- leaking hot water not only does damage to the surrounding area but causes the tank to heat much more frequently.

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Can a water heater be moved to make more usable space? My new water heater is ‘fatter’ and doesn’t fit in the current space, what can I do?

We commonly relocate water heaters, most often to metal enclosures made just for that purpose. People love to free up space for other things. With housing construction costs at over $200 per square foot, a person could say that if your interior closet space is 3′ x 4′ it would be worth about $2400. An enclosure outside can be a money-saving move. Many people also feel safer with the water heater outside, where if it leaks the chance of water damage is minimized.

This is the perfect time to relocate the new heater to an enclosure outside. They make metal enclosures or “sheds” specially designed for new hot water heaters. You can relocate your water heater to the outside in one of these “sheds” and free up storage space in your home. back to top

What considerations do you suggest when sizing a replacement water heater?

Several factors we suggest considering: Is your need for hot water growing, staying about the same, or diminishing? Is it possible that your heater seemed undersized due to a build-up of sediment in the bottom? Are you planning on moving in the near future and if so, what size might a prospective buyer expect in your size home? Does it ruin your day when you run out of hot water [link to post] or is it just a minor inconvenience? Are you willing to space your shower and laundry usage to avoid running out of hot water? How important is energy conservation and water conservation to you? back to top

What is the best water heater for me to purchase?

There are many options for water heaters when it comes time for a replacement. The most important factors to consider when choosing a water heater are:

  • the size and usage of your household
  • your future water demands
  • how long you plan to stay in your current home

We suggest you do a little research and check out your options before making a final purchase. Traditional tank hot water heaters come in sizes from 30 gallons all the way to 100 gallons, and offer gas, electric or propane types.  Tankless and high efficiency water heaters are rapidly increasing in popularity for their energy and water saving benefits. Our water heater experts will be happy to discuss with you the types of water heaters available today. If you have any questions, please feel free to contact us 24 hours a day 7 days a week at 1-866-946-7842. back to top

What does the Energy Factor (EF) of a water heater mean?

The water heater Energy Factor or EF is a measure of the overall efficiency of the water heater. This is determined by comparing the energy in the heated water used daily to the total daily energy consumption of the water heater. The energy factor can be used to compare the energy efficiency of water heaters. Water heaters with higher EFs will have lower annual operating costs than comparable models with lower EFs. A higher EF signifies a more efficient model. Water heaters with high EF ratings may cost more initially, but will save energy and money in the long run. They can often pay for themselves over the water heater’s lifespan. back to top

What is the FHR (first hour rating) on a water heater?

The first hour rating on a water heater is the total amount of water that a water heater will produce in an hour of usage. This is usually a combination of the tank capacity / gallons plus the amount of water the water heater can reheat in a one-hour time period. back to top

Why does my hot water smell bad? Is that dangerous?

When a water heater produces smelly water, it can relate to the mineral compound in the water supply reacting with the inside of the water heater. Depending on the chemical content of your water, sometimes a water heater can produce “smelly water”. The combined presence of hydrogen, sulfur, and bacteria cause foul smelling water, including that “rotten egg smell”. The magnesium anode rod installed in the tank protects the tank surface but generates enough hydrogen to create an odor when it interacts with sulfur in the water or bacteria in the tank. Replacing the magnesium anode rod with another type of anode may alleviate the problem. The most efficient method of eliminating the hydrogen sulfide odor is to control the bacteria. As a rule, chlorination of public water supplies kills the bacteria, but some private well systems may need to be purified to destroy the bacteria. Rarely is it a dangerous situation, but as a precaution you should speak to a water heater professional regarding smelly or discolored water. back to top

How frequently should a tankless water heater be flushed?

A tankless water heater should be flushed once a year to keep it running properly. It is good to know this before deciding to install one. Call us to send a tech out who can do it for you. back to top

What is an anode rod and why is it important?

The anode is a ‘sacrificial’ rod that hangs down into the water heater tank, made of certain elements like magnesium, and meant to attract harmful minerals and particles. This causes the anode rod to corrode first before the rest of the tank, thus extending the life of the water heater. Anode rods can be replaceable in the right circumstances, but not always. back to top

Where is the “dip tube” located on my water heater?

The dip tube is another name for the cold water inlet. If you are facing the front of the water heater (where the labels are), the cold water inlet or dip tube is generally on the cold water input on the right-hand side of the water heater. This “dip tube” allows the cold water to travel to the bottom of the water heater to be heated and not mix with the hot water at the top of the water heater, so there is a supply of hot water ready for use. back to top

What is thermal expansion?

Water expands when it heats up, creating a thermal expansion in the water heater, and this added pressure needs somewhere to go. While there is a temperature and pressure relief valve on the tank as a safety measure, It is NOT designed to handle the daily work of relieving thermal expansion. Such reliance can shorten the life of the valve and even the water heater! A thermal expansion tank, or thermal expansion bottle, is installed to ensure this issue is maintained correctly, and in some situations is even required by code with a new water heater installation. Sitting above the tank at various distances, sometimes blue, sometimes white, constructed to regularly allow excess pressure into it. back to top

My home water pressure is 90 lbs. per square inch, is this a good thing?

The legal limit for home water pressure is almost always 80lb for good reason. People often think they want the highest pressure possible, however, good volume is what you need, which is different in that it comes from properly sized piping. Too high of pressure is very hard on plumbing fixtures and creates unwanted noise. Solenoid valves that operate dishwashers and washing machines are expensive and not designed for this high pressure. Even the typical toilet ball-cock valve can’t take the excess pressure and will often need replacing prematurely. Our technicians can check your pressure and install a PRV (pressure reducing valve) back to top

Do I need straps on my water heater to keep it in place? Is this a law?

The State of California requires that all water heaters must be strapped to resist motion during an earthquake. They must be strapped with either 2 or 3 straps, depending on the size of the water heater.  If you have any questions in regards to having your water heater properly secured, you can ask one of our water heater experts. back to top

How does the warranty work?

To us, it is important that the company that installs your water also provide the warranty service. The manufacturer will always honor the warranty, but you need to have a reliable company that will diagnose and service the water heater in the event there is an issue within the warranty period. Not all companies service the brands they install.

Water Heaters Only, Inc. always backs the warranty on the units we install. Our customers are very important to us and we don’t believe in referring them to a different service company for warranty work after the installation is complete. back to top


If you have any questions not addressed in our water heater FAQ, just call us for quality, professional water heater help, service and installation. Water Heaters Only, Inc. professionally services these areas:

San Francisco Bay Area | (800) 835-5946
Greater Sacramento Area | (916) 448-2113
Greater Los Angeles Area | (800) 833-4571
Orange County | (800) 833-4571
Riverside / Inland Empire | (800) 833-4571
San Diego | (800) 833-4570
Dallas / Fort Worth, TX | (800) 835-8041
Phoenix, AZ | (800) 835-0077

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