John Moore Services
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Houston Area Water Heater Repair, Replacement, & Maintenance

John Moore Electrical Van

Water Heater Services by Houston’s Most Dependable & Trusted Name in Plumbing Services Since 1965

Why deal with the headaches of repairing your own water heater when John Moore has licensed repair and installation pros who can get it done quickly and correctly? With same day services, we’ll get your hot water back running the way it used to. Give us a call today! In-House Financing and an industry-leading 13-year Parts & Labor Warranty available only at John Moore.

  • Tank-Style Water Heater only $19/mo
  • John Moore 13 Year Warranty
  • All Makes & Models
  • Tankless Water Heaters
  • Point-of-Use Tankless Heaters
  • Gas Water Heaters
  • Electric Water Heaters
  • Water Heater Upgrades
  • Repairs & Replacement
  • In-House Financing
  • Plumbers are Fully Licensed & Insured
  • Over 50 Years in Houston

Water Heaters 101

Understanding how your water heater works

It’s in your best interest to understand how your water heater works so that you can properly maintain it and get the most out of your home’s hot water system. If your water heater stops working as it should, knowing the basics can potentially save you time and money, and will better prepare you for repair or replacement options. Although there are various water heater types, the two most common are tank water heaters and tankless water heaters. Both tank-type and tankless models can be either gas-fired or electric (although John Moore does not install electric tankless water heaters). The majority of Houston homes use tank water heaters. However, tankless water heaters are becoming standard in new developments, so if you live in a newer home or a home that has recently been remodeled, you may have a tankless system supplying hot water to your home.

Tank Water Heaters

Tank water heaters are easy to spot; they comprise a large cylindrical hot water storage tank standing on end with pipes coming out of the top and a drain cock towards the bottom. Tank-type water heaters not only heat water but also store it in a tank until it’s ready for use. Typically, water heater tanks are made of steel and lined with glass to prevent the steel from rusting. They are also insulated to keep the water hot between heating cycles.

How Hot Water Storage Tanks are Sized

Water heater tanks range in size, with the smallest tanks holding around 23 gallons and the largest holding more than 56 gallons. For the purpose of cost and efficiency, it’s important to have an appropriately sized hot water storage tank. If it’s too big, you may be spending more money than necessary to heat up the water within the tank. If it’s too small, your family may run out of hot water throughout the day.

The size of your home, appliances, and family are all important factors to consider when determining the size of your hot water storage tank. But the most important question to ask yourself is, “How much hot water does my family use?”. If you only have four people living in your home, but they all take hot baths (which consume more hot water than showers) and frequently wash their clothes, you may need a larger sized storage tank. Likewise, if you have a large family, but everyone takes showers and conserves water, then a medium sized hot water storage tank may suffice.

How Tank-Type Water Heaters Work

Water heaterThe two pipes coming out of the top of every water heater tank are the supply and delivery pipes; one is the cold-water inlet pipe and the other is the hot-water outlet pipe. The cold-water inlet pipe carries cold water from your home’s water supply into the tank where it comes out of the dip tube, filling the tank with water to be heated. The hot-water outlet pipe carries hot water from the tank to the various appliances and faucets around your home when they need hot water.

All hot water storage tanks include a critical safety feature: the temperature and pressure valve, which is often referred to as the T&P valve. If the water gets too hot or the pressure in the tank is too high, the T&P valve will open and deposit water through a pipe running outside of the tank that usually ends 6 inches above the ground. We advise homeowners to keep a bucket underneath the T&P deposit pipe to catch water in case the T&P valve opens. The T&P deposit pipe should not be connected to a drain; if the valve opens and the water goes down a drain, you might miss early warning signs of a problem in your water heater that could worsen if not addressed.

Another feature found in water heater tanks is a magnesium rod known as a sacrificial anode rod. Corrosion and rust are primary reasons that most tank-type water heaters fail. Sacrificial anode rods are designed to corrode, temporarily saving the steel casing and internal components from rusting (hence why this rod is referred to as ‘sacrificial’). Because the anode rod wears away over time, it’s important to inspect and replace it as needed in order to maintain your water heater. If the sacrificial anode rod is not replaced once it has been fully corroded, your hot water storage tank will begin to corrode, meaning you will probably have to replace it prematurely.

In addition to checking the sacrificial anode rod at least once a year, it’s also important to flush your hot water storage tank to prevent build up of minerals and deposits that slow down the heating process, accelerate corrosion, and destroy internal components. (If your water heater sounds like a jackhammer, it’s because calcium and magnesium in your water have formed into solid rocks inside of your water heater). The drain cock located at the bottom of the hot water storage tank is where you or a service technician can flush the tank.

Important: Before flushing your hot water storage tank, you must first shut off the thermostat, turn off the gas, close the cold water valve, turn on a hot water valve in a sink or tub in your home, and open the T&P valve. It is also highly recommended that you connect a garden hose to your drain cock to direct the water being flushed outside of your home. To take advantage of our water heater flush and inspection service, contact us today!

That covers the basic operations, safety and maintenance features of tank-type water heaters. But now you may be asking yourself, “How does the water get hot?” That depends on whether you have a gas-fired tank-type water heater or an electrical tank-type water heater.

How Gas-fired Tank-type Water Heaters Heat Water

Gas-fired tank-type water heaters use a burner centered underneath the tank to heat the hot water storage tank, which in turn heats the water within the tank. Gas is fed to the burner through a gas control valve and thermostat switch that are usually located toward the bottom of the hot water storage tank. The gas coming out of the burner is ignited via pilot light. Natural gas and liquid propane (LP) are the two most common types of gases used in gas-fired water heaters.

The combustion of gases within gas-fired tank-type water heaters create by-products such as carbon dioxide, carbon monoxide, and nitrogen oxide that are removed through a flue baffle that runs through the water heater storage tank. The flue baffle turns into a vent that exits through the top of the hot water storage tank and runs through a wall or ceiling, releasing the by-products outside of the home.

Wrapped around the vent that comes out of the top of a gas-fired hot water storage tank, there should be a round, bell-shaped (or cone-shaped) piece of metal called a draft hood. This hood prevents backdraft, which is when the combustion by-products are blown back into the home or water heater system. Not only does backdraft prevent the venting of harmful by-products but it can also blow out the pilot light

How Electric Tank-Type Water Heaters Heat Water

Electric tank-type heaters utilize electrical-resistance heating elements located within the hot water storage tank to heat up the water within the tank. There are usually two heating elements inside the storage tank, one located near the bottom and one located in the middle of the tank. A thermostat that controls and senses the temperature of the water within the tank delivers power to the heating elements when it detects that the temperature of the water is below the temperature set on the thermostat. Instead of a vent, electric tank-type water heaters have a 220-volt power supply cable going into the top of the hot water storage tank that supplies electricity to the thermostat and heating elements.

Tankless Water Heaters

If there is no large, cylindrical hot water storage tank in your home, chances are that you have a tankless water heater. Although they are often more expensive than tank-type water heaters, there are many advantages to going tankless. Also known as instantaneous or on-demand water heaters, tankless systems only produce hot water when you need it, and they do so with close to zero lag time. Tankless water heaters often save homeowners money because they only heat water as it’s being used as opposed to continuously using energy to keep a tank of water warm throughout the day. Like a pay-as-you-go plan, you only pay for the hot water you use. Because tankless water heaters don’t require as much maintenance and can last up to 25 years, they usually pay for themselves. They also take up far less space than a tank-type water heater.

Another difference with tankless water heaters is that they produce water at a much hotter temperature since it’s coming directly from the heating element instead of a holding tank. For this reason, we recommend that a thermostatic mixing valve be installed to prevent scalding.

How Gas-Fired Tankless Water Heaters Work

TanklessAs mentioned above, gas-fired tankless water heaters only heat up water when you need it. How does this work? When you turn on a hot water valve or an appliance that draws hot water such as a washing machine or dishwasher, the gas-fired tankless water heater will draw cold water in through the cold-water inlet pipe on one side. The cold water flowing into the system hits a flow sensor inside the unit that relays a signal to the computer within the water heater. The computer pulls in gas and ignites a fire within the contained burner, which provides heat to the heat exchanger. The incoming water is then circulated through the activated heat exchanger, heating the water to the temperature set on the thermostat before leaving the system through the hot water outlet pipe where it is directed to the appropriate faucet or appliance. This all happens within seconds, effectively giving homeowners instant access to hot water. When there is no demand for hot water, the system shuts itself off.

Similar to gas-fired tank-type systems, gas-fired tankless systems include a vent that removes any by-products created during the combustion process. A small fan underneath the burner propels the by-products up through the vent, where they are carried outside of the home.

Point-of-Use Tankless Water Heaters

Point-of-use units are used to quickly supply hot water to a source not located near the home’s central water heater. These units are not intended to replace a water heater, but instead are luxury add-ons to a home with a functioning water heater. Much like whole-home tankless water heaters, point-of-use units don’t have to keep a tank of water warm and only operate when hot water is in use.

Circulation Pumps

Circulation pumps are also used to supply warm water more quickly to a source as you use it. The difference between point-of-use units and circulation pumps is that a point-of-use unit heats water at the source, while a circulation pump keeps warm water flowing through your home and back to the water heater so that there is a constant stream of warm water passing through your home’s pipes.

Call 877-730-2525 and schedule a Water Heater Specialist.


Whether it's used for taking showers and baths, washing clothes, or cleaning dishes, hot water is a luxury of modern living.

A hot shower may be part of your morning routine, or you may unwind with a hot bath after a long day at work. Hot water supplied to your sinks, washing machine, and dishwasher makes ridding clothes and dishes of germs and grime a simple task. It’s easy to take hot water for granted until your water heater stops working. If you’ve ever waited for your bath water to warm with no results, then you know how frustrating it can be when your water heater isn’t working as it should.

You probably don’t think much about your water heater. Chances are it sits somewhere in your house and the only time it crosses your mind is when it’s out of order or starts making noises. Although water heaters are designed to be relatively self-reliant, they do require regular maintenance. It’s important to maintain your home’s water heater by flushing the system once or twice a year. You may also need to consider whether your water heater is built to meet all of your family’s hot water needs. Especially for new parents, you may find that you’re using more hot water in your home to bathe your children, wash clothes, and clean dishes, which in turn could mean that you’re running out of hot water more often throughout the day.

When it comes to water heater maintenance, repairs, and replacements, the pros at John Moore are here to help. For more than 50 years, John Moore’s licensed plumbers have helped Houston homeowners be proactive about their homes’ water heaters.

Signs That Your Water Heater Needs an Inspection

Have you noticed a leak in your water heater tank? Is it taking longer than usual for your water to warm? Is water coming out cold altogether?

Any one of these issues could be a sign that your water heater is in need of inspection. The problem could be a result of poor upkeep, or might suggest that your water heater tank is not appropriately sized to accommodate all of your family’s needs. Regular preventative maintenance is the best way to extend the life of your water heater; a well maintained water heater could potentially last for decades.

Whether you have a tank water heater or a tankless water heater, the professionals at John Moore can keep your home’s hot water system running as it should. When it comes time to replace your water heater, we can also help you choose the best option for your family’s needs and budget. We understand that many homeowners don’t expect to replace their water heater until a major problem occurs. To ease the financial burden of replacing your water heater, John Moore offers 0% down financing for qualified homeowners.

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13 Year Warranty

Water Heater Replacement

At John Moore, we stand behind our water heater work a long time. In fact, across all our services, nobody beats our water heater replacement warranties.

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John Moore Water Heater Services and Solutions

Backed by the John Moore 13-Year Labor Warranty
All John Moore water heater installations (except for Economy) come with a 13-year labor warranty*. For Economy installations, we offer a six-year manufacturer’s warranty if maintained. John Moore is also proud to offer reputable water heater brands like Rheem and Rinnai. Rheem water heaters all come with their own parts and labor warranties at 7, 9, and 13 years, depending on the model.
*Warranty can be voided by consumer negligence, which includes lack of maintenance. Does not cover damage due to riots, war, or acts of God.
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Water Heater Repairs and Replacements

When it comes to water heater repair and replacement, we take the time to examine the issue, communicate, and determine the best solutions for your home and your needs. Sometimes, a water heater problem can be solved with a simple repair, in which case we will use high-quality parts. Other times, a replacement may be necessary. If it’s time for a replacement, we will help you determine the best option according to the design of your home and your family’s needs and budget.

We highly recommend that homeowners stay proactive by maintaining their water heaters. We offer water heater maintenance and inspection so that you don’t have to go through the hassle or confusion of flushing and inspecting your water heater.

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Water Heater Maintenance

There are several ways you can keep up with their water heater without getting your hands dirty. While maintenance on water heaters is fairly simple, we still recommend you have a professional handle it to make sure everything is functioning as it should.

One of the most important ways to maintain the functionality of a tank-type water heater is to flush the tank. As your water heater pulls water in, it’s common that traces of sediment will deposit onto the bottom of your tank. Picture trying to warm a pot of water over a fire, but between the fire and the pot is a stack of bricks. With sediment piling up on the bottom of your tank, your water heater is trying to heat water through the mound of dirt, leading to a longer wait time for your water to heat. John Moore recommends a good flush at least once a year, but twice is preferred for larger households that use more hot water.

In addition to flushing the tank, regular inspection of your tank is essential. As mentioned in the Water Heaters 101 section of this page, your tank also has a “sacrificial anode rod” inside, which is meant to corrode in place of the tank or internal components. But once it’s gone, you’ll need a new one to prevent corrosion of your tank.

If your tank is gas powered, you’ll find gas connections below the tank at the pilot light. During inspection, we’ll make sure the gas is connected properly and that it cuts on and off as it should. When your water isn’t heating properly, the problem could be something as simple as an extinguished pilot light. Inspecting these components are all parts of the John Moore water heater inspection.

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Water Quality Upgrades

Although flushing your water heater storage tank and replacing the sacrificial anode rod are ways to actively maintain your water heater, improving the quality of water within your home is a way to passively maintain your water heater. Soft, clean water flowing through your home is your first line of defense against corrosion and buildup in your water heater. Hard water is the lead contributor of calcium buildup. As the treatment chemicals from the city are heated in your water heater, calcium forms, causing buildup. Calcium build-up not only causes damage to the tank but also causes an unpleasant banging noise when the tank kicks on as the hard calcium deposits are shuffled around inside. Installing a whole-house water softener can mitigate calcium buildup, lengthening the life of your water heater.

John Moore installs whole-home filtration systems, water softeners, and Flow-Tech calcium and magnesium neutralisers as part of our water quality services. Installing a water filtration system can assist in preventing the issue of sediment buildup that we mentioned, which can save your tank from holding mounds of dirt between inspections.

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John Moore’s Lifetime Water Heaters

Upgrade your water heater to a lifetime of no-hassle maintenance with a John Moore Lifetime Water Heater unit. The John Moore Lifetime line brings you peace of mind by providing premium water heater units that are covered by a Lifetime Unit Replacement Limited Warranty for as long as you, the original purchaser, own your home.

John Moore’s Lifetime Water Heaters

  • The Lifetime Unit Replacement Limited Warranty is valid for as long as the original purchaser owns their home.
  • Each John Moore Lifetime unit is upgraded with top-of-the-line parts.
  • Protect yourself against higher future replacement costs due to inflation and higher costs of living.

If you’re ready for a worry-free water heater, set up an appointment with a John Moore Technician to see if a John Moore Lifetime unit would be a good fit for your home.


All John Moore water heater installations (except for Economy) come with a 13-year labor warranty*. For Economy installations, we offer a six-year manufacturer’s warranty if maintained. John Moore is also proud to offer reputable water heater brands like Rheem and Rinnai. Rheem water heaters all come with their own parts and labor warranties at 7, 9, and 13 years, depending on the model.
*Warranty can be voided by consumer negligence, which includes lack of maintenance. Does not cover damage to to riots, war, or acts of God.
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(877) 730-2525

*Limit one per household. Some restrictions may apply. Cannot combine offers. Expires 12/31/2018.


Tankless Water Heater System

Save $100 on a tankless water heater system.

John Moore

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Traditional Water Heater

Save $40 on a water heater replacement.

John Moore

(877) 730-2525

*Limit one per household. Some restrictions may apply. Cannot combine offers. Expires 12/31/2018.


Service Areas

We provide Water Heater Services to the Houston Metro area including:
  • Alvin
  • Baytown
  • Bellaire
  • Champions Forest
  • Channelview
  • Clear Lake
  • Cinco Ranch Conroe
  • Cypress
  • Deer Park
  • Fresno
  • Friendswood
  • Galena Park
  • Heights
  • Humble
  • Jersey Village
  • Katy
  • Kingwood
  • La Porte
  • League City
  • Manvel
  • Meadows Place
  • Memorial
  • Missouri City
  • Pasadena
  • Pearland
  • Richmond
  • River Oaks
  • Rosenberg
  • Seabrook
  • Shenandoah
  • Sherwood Forest
  • Spring
  • Spring Branch
  • Stafford
  • Sugar Land
  • Tanglewood
  • The Woodlands
  • Tomball
  • West University
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(877) 730-2525

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