Bath Maintenance Tankless Water Heaters

Can I Install a Water Heater Myself?

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Today, there are many offline and online tutorials and videos that provide step-by-step guides on how to install water heaters. While the information makes it look like it is easy to do the installation, it might not be a good idea to do it yourself, especially if you have never done it before. 

Most often, the tutorials will give you step-by-step instructions based on an ideal situation. However, your environment and skills are also vital and will determine how you do the work. Moreover, it is not just the physical placement; there are various issues such as the electrical system, gas piping system, venting, access, and other factors that determine performance, reliability, and safety. 

Ideally, it is advisable to seek professional help, especially if you do not have the necessary technical skills. However, if you have these, you can do the installation as long as you ensure that you adhere to all the codes, regulations, and safety precautions. 

Generally, the installation process of a hot water system is a multi-disciplinary exercise that requires knowledge in plumbing, electrical, safety, and others. Additionally, in some countries, you need to comply with relevant codes and obtain permits to perform the work. That said, while you can install the small point-of-use tankless water heaters and especially the plug-in types, you need to consider engaging a professional installer when you have large multi-user water heaters.

Risks of installing a water heater incorrectly

While proper installation and regular maintenance ensure safe and reliable operations, the system will fail when it reaches its end of service life. However, a wrong installation is risky and more dangerous than a normal failure.

Hot water systems are dangerous

Usually, problems with the electrical or gas systems are dangerous and can lead to short circuits, explosions, fires, and other situations. If you are replacing an older system, you need to safely remove it and prepare the space for the new water heater. The heaters use an energy source. This could be gas, electricity, or both, and you must ensure the safe and reliable infrastructure to safely deliver these to the heater system. Incorrect wiring could cause electric shocks or fires. Also, if your heater is propane or natural gas-powered, you need proper piping and connections, otherwise, a minor leak from poor installation may lead to fire risks and explosions. 

Also, failure to install the water heater properly could lead to pressure build-up and tank explosion. 

Voiding warranty

Most manufacturers and even insurance policies will only honor claims for systems installed according to set requirements. In most cases, they require a professional and licensed plumber or installer. Failure to do this will void the warranty or insurance cover.

Time factor

Even when you have technical skills in other fields, installing some water heater models is quite involving and may take you longer than what you save by avoiding a professional. 

Generally, installing your water heater improperly and failing to comply with relevant plumbing, building, and electrical codes could expose yourself and your family to financial, safety, and legal risks. For the above and other reasons, you may need to think twice about installing a water heater by yourself. While you will save some money, the benefits may not warrant taking the risk.

To determine if you can install your water heater by yourself, below is a typical guide on how to perform the replacement or a new installation of an electric-powered model.

How to install a water heater 

If you decide to install the water heater, below are some of the basic steps. Please note that these may vary from one type and model of a water heater to another. Other factors that affect the installation procedure include the type of fuel, whether gas or electric, tank or tankless, capacity, outdoor or indoor, and other issues. While you can install some small models such as the point of use (POUs) and other low-demand models, the procedures may be complex for larger models.

Tools to install a water heater

Below is a list of tools to do the installation.

  • A set of screwdrivers
  • Wrench
  • Flexible hoses
  • Pipe cutter
  • Plumbers tape
  • Voltage detector
  • Soldering iron or torch
  • Solder wire
  • Solder flux
  • Sandpaper cloth, dielectric connectors, etc. (optional)

Step by step instructions on how to install an electric water heater

In our guide, we are assuming that you are replacing a defective system. You will, therefore, first remove the old one and then install the new heater.

Switch off the electrical supply to the water heater

Before working on the water heater, disconnect the power at the panel. Ideally, switch off the water heater’s circuit breaker. Use a voltage detector to ensure that the wires at the heater do not have any power. 

electric circuit breaker

Empty the tank 

If you are replacing a storage-based water heater, empty the tank by

  • Open one of the hot water outlets and letting the water run until it is cold.
  • Afterward, turn off the water heater cold water supply.
  • Use the drain valve to remove all the water from the tank. You may use a hosepipe to pour the water outside or into a sink.
  • To drain the tank faster and allow air to move in, open the hot water faucet and the T&P valve.

Physically disconnect the electrical wires

To avoid confusion, sketch the wiring diagram before removing the wires. If possible, take a photo of the wiring before disconnecting. 

Remove the electrical wires supplying the water heater. Before touching the cables, confirm again that the circuit breaker is off and that they are not carrying any current. As you remove each wire, ensure that you label or mark them appropriately.

Detach the water pipes 

Remove both the water input and output pipes. If the pipe is damaged, you may cut the pipe, but leave as much of the good part as possible. However, if the pipe is still in a good position, you can use it with the new unit, and you need to remove it carefully.

Replace the water heater

Remove the old empty water heater and move it out of the way.

Place the new heater and align it well so that electrical and plumbing connections will fit properly

Prepare the pipes

You need to prepare the old pipes by thoroughly cleaning them with sandpaper. Clean the ends that will connect to the new heater until they are shiny and free of rust and other debris.

Connect the electrical wires

Use the wiring diagram provided by the manufacturer to connect the electrical wires. Ensure that you have grounded the tank by connecting the green wire appropriately. Once done, cover the junction box securely.

install a water heater

Attach the water supply lines

  • With the unit aligned correctly, attach the cold and hot water pipes in their respective positions. 
  • If not already in place, a good practice is to use flexible hoses to attach the heater inlet and outlet and the cold and hot water copper pipes, respectively. The flexibility enhances safety and especially in case of an earthquake. When making connections use the plumber’s tape to line the threads and ensure tight bonding.
  • Open the nearest hot water faucet and turn on the cold water supply to the water heater.
  • Check for leakages, and if none, continue and fill the tank with water. 

Connect the temperature and pressure discharge pipe

  • Use the appropriate fitting to attach the discharge pipe to the T&P valve.
  • Ensure that the pipes’ ends and fittings are clean before attaching them.
  • You may use the solder to make the connections. 

Reconnect the electrical power supply 

Once you fill the tank with cold water, switch on the circuit breaker at the service. If all is well and the connections are correct, the power should reach the water heater. If there is no electrical power on the water heater, turn off the breaker before checking the wiring.

NB: Do not apply the power when the tank does not have enough water since this will cause the heating elements to dry fire and burn if not fully submerged. 

Supply all the hot water lines

Open each hot water outlet and let the water run for some time until it stops sputtering. Doing this removes the air from the tank and pipes.

Set the temperature at about 120 degrees Fahrenheit let the water heat for some time. The process may take a few hours to heat and reach the set temperature. While in the process, monitor the discharge pipe. If it starts dripping, know that the pressure could be too high and make the necessary adjustments.

While this guide assumes that you are replacing an old water heater, it is also applicable if you have a new unit. If installing the new system, skip the first five steps and start at step 6.

Common mistakes to avoid when installing a water heater

While the installation may vary depending on the type of water heater, energy source, environment, and other factors, there are some common mistakes that you should avoid. These include;

Incorrect water heater sizing

It is vital to ensure that the water heating system is the right size. Otherwise, a small unit will need to run for a much longer time, hence wear out much faster. 

install water heater

Similarly, a much larger system will cost more in terms of purchase and running costs. Additionally, it will take up more space and more costly accessories.

Placing the gas or electrical power shut-offs out of site

These controls must be in easy to access and visible locations for normal operations and handling emergencies. They allow you to cut off the electrical supply or flow of the gas into the tanks.  

In practice, you should never heat an empty tank. However, if the shut-off is inaccessible, it means that you must leave it on, even before you complete the installation and added water to the tanks. Consequently, immersion heating elements, which must work when in water, will overheat and burn out. Similarly, if you apply a flame to an empty tank, it will overheat and crack the tank.

Installing the water heater in a difficult location

A difficult-to-access location can be a challenge when installing and maintaining the water heater. Additionally, it may be risky to work in such as place and could also pose other hazards. Usually, the building codes recommend the minimum dimensions you require to access the water heater. They also specify the minimum floor space required to install the heater. Failure to adhere to the building codes results in difficulty installation and challenges in putting the units and tank in and out of the tight spaces.

Loose gas supply pipes and electrical wires

Ideally, you need to secure the electrical power and gas supply lines to the walls and floors to minimize vibrations, loose connections, movements, and associated risks. Also, ensure that they are out of the way from other objects to prevent damage. Where necessary, protect the lines, such as using the appropriate conduit or trunking for the electrical wires.

Other errors include

  • Mixing different metals: – increases the risk of galvanic corrosion. In case there is a need to use two types of metals. Separate them with a dielectric connector to avoid direct contact.
  • Ineffective venting of the exhaust gases in gas-powered based water heaters
  • Replacing a good and serviceable water heater
  • Poor soldering
  • Installing the wrongly sized water heater, etc


While, in most cases, nothing prevents you from installing your water heater, you need to understand what is involved, the risks and impact of your actions. What you need to know is that installing the water heater is not an average DIY project, and could lead to serious performance and safety issues. The installation requires a broad set of skills, including plumbing, electrical, ventilation, carpentry, and more, depending on the environment and where you are installing the system.

Reviews Tankless Water Heaters

Tankless gas water heater reviews and buying guide

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A gas tankless water heater uses the same heating process as the traditional tank-based gas systems. However, it does not have a storage tank, and will only heat the water when a user needs it, hence significant energy savings. 

In the storage-based systems, the hot water losses some energy during the standby period, and this does not happen in the tankless hence more on savings heating costs.

The heaters require less space while lasting much longer and providing you with unlimited hot water at any time. However, the systems are more costly than the storage-based, and some models may require an expensive vent system and an upgrade of the natural gas line. That said, the savings in energy, operational, and maintenance costs make the tankless system more cost-effective in the long term. 

How a tankless gas water heater works

Once you turn on a hot water tap, the tankless hearer draws the cold water. A flow sensor detects the water and activates the gas burner that then heats the heat exchanger.

The natural or propane gas, depending on the model, flows into the burner upon which a flame or electrical spark ignites it. The heat from the burner heats the heat exchanger, which, in turn, heats the incoming water to the desired or set temperature. Consequently, the system delivers hot water almost instantly. A vent pipe then safely exhausts the combustion gases to the outside.

Turning off the shower, sink, or another faucet, will stop the flow and the gas flame will go off, hence shutting down the heating process. As such, the heater will only operate when there is a need for hot water, and this delivers significant energy savings since there are no losses when on standby.

Benefits of tankless gas water heaters

Tankless gas heaters provide a wide range of operational, financial, and environmental benefits. These include but not limited to;

  • Provides endless hot water on demand
  • Durable with a long service life of about 20 years 
  • Higher energy efficiency and saving on heating costs
  • Less risk of water leaks since there is no storage task
  • Easy and inexpensive maintenance
  • Environmentally friendly 
  • Uses less expensive natural gas or propane for energy 
  • Flexible indoor or outdoor installation options

Disadvantages of tankless gas water heater

Despite the many benefits, the tankless systems have drawbacks such as;

  • Requires expensive stainless steel tubes for venting 
  • Requires annual servicing hence increasing operational costs
  • High up-front costs which could be almost three times that of a storage tank based heater
  • Requires good plumbing work to ensure that the water has enough pressure
  • When there are multiple uses, the budget systems will split the available hot water among the fixtures. in turn, this leads to fluctuating temperatures, inconsistent flows, and some discomfort.

Factors to consider when looking for a tankless gas water heater

There are various issues to factor in when looking for an on-demand gas water heater. Paying attention to these ensures that you acquire a system that best matches your requirements. 

While you may not get the exact features and performance per your expectations, you can settle on a product that ticks most of the boxes. The main things to look for include;

Physical dimensions or size

Space, where you want to install the system, influences the size of the gas heater that you purchase. Ideally, you should get a heater that will fit comfortably in your available or the preferred location. Generally, most gas tankless water heaters are larger than the electric models. The heaters often have an exhaust system that takes up some extra space.

Tankless gas water heater reviews

Type of fuel the heater uses

You have a choice between propane and natural gas. However, propane provides more benefits, including higher efficiency hence low fuel usage. Compared to the natural gas and electric models, propane has fewer emissions and therefore environmentally friendly.

Energy factor

A water heater with a higher energy factor (EF) is more efficient, hence delivers more cost savings. As such, a tankless gas water heater with a high EF value results in lower energy bills.


The type of venting for the tankless gas water heater is another consideration since these also differ from one model to the other. Also, the design, appearance, indoor or outdoor installation, and other factors influence the venting system.

Generally, there are two main types of venting; direct-vent and power-vent. Each of these exhausts to the outside. However, for combustion, the direct pull air from outside and will require two pipes intake and one for exhaust. On the other hand, the power vent uses the indoor air and only requires one exhaust pipe.

This brings about placement issues since a power vent requires larger rooms to provide adequate gas for combustion. Alternatively, a room with vents and an opening to bring in fresh air for combustion is also suitable.

The direct vent types do not require a large room and can be placed in a wide range of smaller spaces. 


To ensure the safety of users and the heater, it is important lookout for a model that has protection against various conditions. That said, this may also vary depending on your location, For example, anti-freeze protection is critical in areas that suffer from freezing but may not be necessary for warmer climates. Other safety features include overheating protection, surge protection, low water flow protection, high water pressure protection, etc. 

Capacity in gallons per minute 

The capacity of the hot water unit depends on your requirements. For single and low-demand applications for small families, you may consider 2-5 gallons per minute. However, if you need more hot water, you need to look for a heater that provides at least 8 gallons per minute.

The warranty period and terms

A longer warranty ensures that the manufacturer has great confidence in the product, and in case anything goes wrong, they will address the issue. Some manufactures may have some conditions to honor the warranty. For example, they insist that you must use a licensed installer. So, even if you have the skills to install the tankless gas heater, doing it by yourself will void the warranty.

Choosing the best tankless gas water heater

Other than the above features, you need to carry out proper research on the models you narrow down on. In particular, you have to pay attention to ease of assembly, mounting, and installation procedures, especially if purchasing online. Although you may have some technical skills to mount the compact heaters, some procedures, such as venting could be beyond your ability and may require professional assistance.

Another thing you need to find out is about the brand, warranty, cost, certifications maintenance, and customer support. For example, the availability of replacement parts as well as the procedure of fixing them yourself. You can check reviews from a wide range of places, including social media, YouTube, shopping websites, and other areas.

Today, there are several reliable brands in the market. However, these differ in the type of gas, size, capacity, and other features. That said, you can get a reliable water heater from established brands such as Camplux, Takagi, Rinnai. Paloma., Noritz, Eccotemp and Gasland.

Best tankless gas water heaters 

Here are some of the best gas tankless water heaters that we recommend. However, the list is not exhaustive.

Rinnai RUC98iN

The Rinnai RUC98iN is a powerful and efficient condensing gas tankless water heater. The 9.8 GPM indoor-only heater has a sleek design and easy access and uses digital control and display. It also emits very little nitrogen oxide (NOx) and therefore environmentally friendly. Additionally, the Rinnai water heater has a high Energy Factor of 0.92, hence reducing heating costs. It is also recirculation pump ready, meaning that if you enable the feature, the heater will provide hot water instantly while allowing you to save on water. An electric ignition system further reduces gas consumption compared to using a pilot light.

Another good feature of the Rinnai is the Wi-Fi capability which allows users to remotely turn the heater on or off, control the output temperature, etc. Additionally, you can use the feature to lock the temperature to ensure that other users do not change to a higher level with energy wastage.

Additionally, the Wi-Fi connectivity allows technicians to access the heater remotely, monitor performance, and carry out diagnostics. As such, a technician can identify the problem remotely and therefore come for the physical repair when prepared, hence saving your time and maintenance costs.

Rinnai RUC98iN gas tankless water heater
Rinnai RUC98iN


The NORITZ NR50OD is a lightweight indoor natural gas-based tankless water heater that delivers endless hot water on demand. Suitable for outdoor applications, the water heater has high energy efficiency with an energy factor of 0.91, hence savings on heating costs. The 120000 BTU, 5 GPM water heaters provide superior hot water delivery and energy savings. 

Further, the NORITZ water heater has very low emissions and is a good choice for indoor applications. It uses advanced carbon reduction technology to ensure the lowest NOx emission compared to other gas heaters.

It comes with a 5-years warranty on internal components, 12 years for the heater, and 1-year labor.

One of the drawbacks is the high purchase cost. 

Takagi T-H3-DV-N indoor natural gas tankless water heater

Takagi T-H3-DV-N indoor natural gas tankless water heater
Takagi T-H3-DV-N indoor natural gas tankless water heater

Takagi T-H3-DV-N is a compact, natural gas tankless water heater that delivers unlimited hot water on demand. You can install the energy-efficient and space-saving heater in various places in your house. The 199,000 BTU, 10GPM heater has several advanced digital features.

Benefits include modern design, being environmentally-friendly, and enhanced safety. Computerized features enable easy temperature control, optimized heating process, significant energy savings, and more. In safety, Takagi includes overheat, surge and freeze protection. It also has diagnostic codes that ease the maintenance procedures. 

However, it is a bit difficult to install and may require a professional installer. But once installed, the Takagi is one of the best gas water heaters. 

The ultra-low NOx emissions heater has a commercial-grade copper alloy heat exchanger, which provides superior heat transfer in addition to being long-lasting. Finally, you get a 15-year warranty in a domestic installation.

Suitable for both residential and commercial applications and can support up to three showers in warm climates.

Click here to buy it on Amazon.

Rheem RTGH-95DVLN Tankless Natural Gas Water Heater

Rheem RTGH 95DLN is a high-efficiency, direct vent natural gas tankless water heater. The 9.5 GPM, indoor-only, water heater is small and easy to install with a 12-year limited warranty. It has inbuilt electronic controls that enhance its safety and energy efficiency. The 199, 900 BTU, low NOx device has a stainless steel condensing heat exchanger, a 94% energy efficiency, and an energy factor (UEF) of 0.93. 


Other features include an inbuilt condensate neutralizer and enhanced water savings. Its low flow activation ensures hot water is available whenever required including times of low demand. Also, it has a hot start programming that reduces the cold water busts while a recirculation pump kit-ready improves water savings.

Rheem RTGH-95DVLN Tankless Natural Gas Water Heater

Click here to buy it on Amazon.

Camplux Pro 26L

Camplux Pro 26L Gas Tankless Water Heater

The Camplux pro 26L is a high-capacity natural gas tankless water heater. With an impressive 6.86 GPM, the large outdoor heater is ideal for high demanding applications. The heater can meet the hot water needs of a large house while supporting up to three showers and a kitchen simultaneously. Its 180000btu/hour output power ensures that water is hot quickly almost at the instant you turn on the tap or faucet.

The easy to install with ultra-low NOx emission includes several safety features such as overheating and freezing protection, flame failure device, low water flow protection, etc. Additionally, it has a simple and aesthetically pleasing design, so you can install it anywhere. The Camplux has a 99 F to 140 F (37-60 C) adjustable temperature range.

The outdoor installation does not require venting hence fewer installation costs in pipes, accessories, and labor. It also has a detached digital control panel which you can install 3.3 feet away from the heater using the provided cable. The remote control allows you to manage the outdoor heater from inside the house.

Click here to buy it on Amazon


Tankless gas water heaters are more efficient since, unlike storage-based systems; they do not continuously heat and store hot water. Additionally, tankless systems have longer lifespans. With regular maintenance, it can serve you for between 15 and 20 years while delivering significant savings on energy, water, and overall operational costs.