Tankless Water Heater Install: A Step-by-Step Guide

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Are you tired of constantly running out of hot water or dealing with a bulky storage tank taking up valuable space in your home? Tankless systems, such as Rheem tankless units, can solve these problems. With tankless models, you’ll never run out of hot water again and you’ll free up space in your home. Well, Rinnai and Rheem tankless gas systems offer an efficient and space-saving alternative to traditional water heaters. With Rinnai tankless systems, tankless units, and tankless models, you’ll never have to worry about running out of hot water again. Their on-demand hot water delivery system ensures a constant supply.

Tankless water heaters are ideal for homes with limited space or high hot water usage. They are a great option for homeowners looking to save on energy costs and reduce their reliance on traditional gas lines. Additionally, professional plumbers can easily install tankless water heaters that run on natural gas, providing an efficient and cost-effective solution for heating water. Whether you’re living in a small apartment or have a large family, these tankless systems are innovative units that provide hot water whenever you need it, without the need for a storage tank. These tankless models use a heat exchanger and are powered by natural gas. Plus, the new water heater models come in both gas and electric options, allowing you to choose between tankless units and tank water heaters for the best fit for your needs.

However, when it comes to installing a new tankless gas water heater, professional installation is crucial for optimal performance and to minimize costs associated with tankless units. The proper installation of gas water heaters ensures that your tankless units, whether electric or vented, operate efficiently and effectively. So if you’re considering upgrading to a tankless gas or electric water heater or need a new water heater altogether, don’t hesitate to reach out to a professional installer who can guide you through the process. Vent and costs are important factors to consider when making your decision.

Cost of Installing a Tankless Water Heater

Installing a tankless water heater may require a higher initial investment compared to traditional water heaters, but the long-term savings on costs and gas make it worth considering. Additionally, tankless water heaters are more energy-efficient, as they use electric power instead of gas. Furthermore, they do not require a vent for ventilation. Several factors influence the costs of installing a tankless water heater, including the size of the unit, the type of fuel (gas or electric), and the complexity of the installation.

Initial Investment Higher than Traditional Water Heaters

It’s important to note that the initial investment for tankless models, whether gas or electric, is generally higher than that of traditional water heaters. The costs of tankless models can vary depending on the type chosen. This is because tankless units utilize advanced gas and electric technology and require specialized equipment for installation, which can help reduce costs over the year. However, despite the higher upfront costs, tankless water heaters can provide significant energy savings on gas expenses throughout the year.

Factors Influencing Cost

The costs of installing a tankless water heater can vary depending on several factors, including gas usage and the number of years in use.

  1. Unit Size: The size or capacity of the tankless water heater plays a role in determining its costs. Gas tankless water heaters, in particular, can save you money on energy bills throughout the year. Larger tankless models capable of supplying hot water to multiple fixtures simultaneously typically come at a higher cost. These models are often powered by gas.
  2. Fuel Type and Costs: Tankless water heaters can be powered by electricity, natural gas, or propane, with varying costs. The choice of fuel type, whether it be gas or electric, will affect both the initial installation cost and ongoing energy costs of tankless water heaters. Gas tankless water heaters and electric tankless water heaters are popular options among consumers, with various tankless models available in the market.
  3. The complexity of installing tankless gas water heaters or electric tankless water heater models also affects the costs. Factors such as existing plumbing infrastructure and accessibility can influence the costs and labor required for installation of tankless gas water heater. When comparing tankless models to traditional tank water heaters, it’s important to consider these factors.

Additional Expenses

In addition to the base costs of the tankless water heater itself, there may be additional expenses associated with installation. These costs can add up quickly, so it’s important to factor them into your budget when considering purchasing a tankless water heater.

  1. Proper venting is crucial for safe operation, efficient performance, and minimizing costs of a tankless water heater. Depending on your home’s layout and existing venting system, the tankless water heater installation costs may require you to invest in additional venting materials or modifications.
  2. Some tankless water heater installation costs may require electrical upgrades to accommodate their power requirements. This could involve upgrading circuit breakers or installing dedicated electrical lines for tankless water heater installation costs.
  3. Permits and Costs: Depending on your local building codes and regulations, obtaining permits for the installation of a tankless water heater may be necessary and can incur additional costs. Permit fees can add to the overall cost.

Professional Installation

While it may be tempting to attempt a DIY installation to save money, it’s recommended to hire a professional for the installation of a tankless water heater. Professional installers have the expertise and experience to ensure proper tankless water heater installation costs setup, which is crucial for optimal performance and warranty coverage.

Steps for Replacing a Tankless Water Heater

Replacing a tankless water heater may seem like a daunting task, but with the right steps and precautions, it can be done smoothly. Here’s a step-by-step guide to help you through the tankless water heater installation costs process.

Turn off power supply and shut off water connections to the old unit

Before you start replacing your tankless water heater, it’s crucial to ensure your safety by turning off the power supply. Locate the circuit breaker or fuse box and switch off the power dedicated to your water heater. Shut off the water connections leading to the old unit by closing the valves on both hot and cold water lines.

Disconnect gas lines or electrical wiring as per manufacturer’s instructions

If your tankless water heater is powered by gas, follow the manufacturer’s instructions to safely disconnect the gas lines. This typically involves shutting off the gas valve leading to the unit and carefully detaching any connected pipes or fittings. If your unit is electric-powered, turn off any electrical switches associated with it and unplug it from its power source.

Remove the old unit carefully, ensuring no damage to surrounding components

With all power sources disconnected, you can now remove your old tankless water heater. Take care not to damage any surrounding components during this process. Depending on how it was installed initially, you might need a wrench or pliers to loosen any bolts or connectors holding it in place. Gently lift and maneuver the unit out of its position.

Install the new tankless water heater following manufacturer guidelines

Now that you’ve successfully removed your old tankless water heater, it’s time to install your new one. Refer to the manufacturer’s guidelines for specific installation instructions tailored to your model. These guidelines will provide details on proper venting requirements, mounting options, pipe connections, and any other necessary steps for installing your particular unit.

Here are some additional tips:

  • Ensure that all connections are secure and leak-free by using appropriate fittings and seals.
  • Double-check the alignment of the venting system to ensure proper exhaust flow.
  • If you’re uncertain about any step, consult a professional plumber or follow up with your manufacturer for clarification.

By following these steps and taking necessary precautions, you can successfully replace your tankless water heater. However, if you’re unsure about any aspect of the installation process or if it seems too complex for you, it’s always best to seek professional help. A licensed plumber will have the expertise and knowledge to handle the installation safely and efficiently.

Remember, safety is paramount when working with gas lines or electrical connections. Taking the time to properly shut off power sources and disconnect utilities will minimize risks during the replacement process. With a little patience and careful attention to detail, you’ll soon be enjoying the benefits of your new tankless water heater!


Switching Off Circuit Breaker and Water Supply

To ensure a safe and smooth tankless water heater installation, there are a few crucial steps you need to take before getting started. One of the first things you should do is switch off the circuit breaker dedicated to the tankless water heater in your electrical panel.

Locate Circuit Breaker and Cut Power

Begin by locating the circuit breaker that controls the power supply to your tankless water heater. This breaker is typically labeled and can be found in your home’s electrical panel. Once you’ve identified the correct breaker, it’s time to cut off the power supply.

Switch off the corresponding circuit breaker by flipping it into the “off” position. This will ensure that no electricity is flowing through the wires connected to your tankless water heater during the installation process. Cutting off power is essential for safety reasons, as it eliminates any risk of electrocution while working with electrical components.

Turn Off Main Water Supply

In addition to cutting off power, it’s equally important to turn off the main water supply connected to your home’s plumbing system. By doing so, you prevent any water from flowing into or out of your tankless water heater during installation.

Locate the main water supply valve, usually located near where your local plumbing enters your home or utility room. Turn this valve clockwise until it is fully closed. This action will shut off all incoming and outgoing water flow, ensuring a dry environment for installing your new tankless water heater.

Follow Manufacturer Safety Precautions

Before proceeding with any installation tasks, make sure to carefully read and follow all safety precautions outlined by the manufacturer in their instruction manual or guidelines. Each brand and model may have specific requirements or recommendations that must be adhered to for proper installation.

It’s also worth noting that installing a tankless water heater may require professional assistance depending on local codes and regulations. If you’re unsure about any aspect of the installation process, it’s best to consult a licensed contractor who specializes in tankless water heater installations.

By switching off the circuit breaker and turning off the main water supply, you’ve taken important steps towards ensuring a safe and successful tankless water heater installation. Following manufacturer safety precautions and seeking professional help when needed will further guarantee a smooth installation process that complies with local codes.

Remember, safety should always be a top priority when working with electrical and plumbing systems. Taking these initial precautions will set you on the right path for a trouble-free tankless water heater installation.

Installing Flow and Pressure Valves

To ensure a smooth and efficient operation of your tankless water heater, it is crucial to properly install flow and pressure valves. These valves play a vital role in regulating the flow rate and maintaining optimal pressure within the system. Let’s dive into the essential steps for installing these valves.

Mount Pressure Relief Valve on Cold-Water Inlet Pipe

The pressure relief valve is designed to release excess pressure from the tankless water heater if it reaches unsafe levels. To install this valve:

  1. Refer to the manufacturer’s instructions for the exact location and mounting requirements.
  2. Typically, you will need to mount it on the cold-water inlet pipe.
  3. Ensure that the valve is positioned in a way that allows easy access for maintenance purposes.

Incorporate Isolation Valves on Hot and Cold-Water Lines

Incorporating isolation valves on both hot and cold-water lines is highly recommended as it allows for easier future maintenance or repairs without disrupting the entire water supply. Here’s what you need to do:

  1. Install isolation valves on both the hot and cold-water lines leading to the tankless water heater.
  2. These valves will enable you to shut off the water supply specifically to the unit when needed, without affecting other areas of your plumbing system.
  3. Make sure that these valves are easily accessible for convenience.

Properly Connect All Pipes Using Appropriate Fittings and Sealants

When connecting pipes for your tankless water heater installation, it is important to use appropriate fittings and sealants to prevent leaks or any potential issues down the line:

  1. Use high-quality fittings that are compatible with your specific piping system.
  2. Apply thread seal tape or pipe joint compound (Teflon tape) on threaded connections to create a watertight seal.
  3. Tighten all connections securely but avoid over-tightening, which could damage threads or cause leaks.

Follow Local Plumbing Codes When Installing Flow and Pressure Valves

Including tankless water heaters, it is crucial to adhere to local plumbing codes and regulations. These codes are in place to ensure safety and proper functioning of the system:

  1. Familiarize yourself with the specific plumbing codes applicable in your area.
  2. Ensure that all installation steps, including the installation of flow and pressure valves, comply with these codes.
  3. If you are unsure about any aspect of the installation process, consult a professional plumber who is knowledgeable about local codes.

By following these steps and guidelines for installing flow and pressure valves, you can enhance the performance and longevity of your tankless water heater system. Remember to always prioritize safety and consult professionals when necessary.


Purging Air and Checking for Leaks

To ensure the optimal performance of your newly installed tankless water heater, it’s important to purge any air from the system and check for leaks. Follow these steps to complete this crucial task:

Turn on hot water taps throughout your home

Start by turning on all the hot water taps in your house, including sinks, showers, and bathtubs. This will allow the water to flow through the system and help purge any air that may have accumulated during installation.

Allow hot water faucets to run until a steady flow is achieved

Let the hot water faucets run for a few minutes until you notice a steady flow without any sputtering or irregularities. This indicates that most of the air has been purged from the pipes and that the system is functioning properly.

Carefully inspect all connections for leaks or drips

After purging the air from your tankless water heater, take some time to thoroughly examine all connections, joints, and fittings for any signs of leaks or drips. Pay close attention to areas such as where pipes connect to each other or where they attach to valves or fixtures.

Repair any leaks promptly

If you do find any leaks during your inspection, it’s essential to address them promptly. Even small drips can lead to significant water damage over time if left unattended. Tighten loose connections or replace faulty components as necessary to prevent further issues.

Checking for leaks in your tankless water heater not only prevents potential damage but also ensures optimal performance and energy efficiency. By addressing leaks early on, you can avoid wasting precious resources like water and energy.

Remember that when dealing with gas systems, such as natural gas or propane-powered tankless water heaters, it’s crucial to prioritize safety. If you suspect a gas leak at any point during installation or maintenance, immediately turn off the gas supply and contact a professional technician.

It’s worth exploring any available rebates or tax credits for installing energy-efficient tankless water heaters. Many utility companies and government programs offer incentives to promote the use of these environmentally friendly appliances.

Mounting the Unit to the Wall

To ensure a successful tankless water heater installation, it’s important to properly mount the unit to the wall. This step is crucial for both safety and functionality. Let’s dive into the key points you need to keep in mind when mounting your tankless water heater.

Select Suitable Location for Mounting

First and foremost, you need to choose a suitable location for mounting your tankless water heater. Consider factors such as accessibility, ventilation, and proximity to plumbing connections. It’s best to consult the manufacturer’s guidelines for specific recommendations regarding placement.

Ensure Proper Clearance from Combustible Materials

When mounting your tankless water heater, it is essential to maintain proper clearance from combustible materials. This includes items such as wood, insulation, or any other flammable substances. Adhering to these clearance requirements will help prevent potential fire hazards and ensure safe operation of your unit.

Securely Mount the Unit Using Appropriate Brackets or Wall Anchors

To ensure stability and longevity of your tankless water heater, it is crucial to securely mount it using appropriate brackets or wall anchors. These will provide support and prevent any movement or vibrations that could potentially damage the unit over time.

Follow Manufacturer Guidelines for Positioning and Securing

Each tankless water heater model may have specific positioning and securing guidelines provided by its manufacturer. It is essential to carefully follow these instructions during installation. Failure to do so may void your warranty or result in improper functioning of the unit.

Additional Tips and Considerations

Here are some additional tips and considerations when mounting your tankless water heater:

  • Take into account the weight of the unit when selecting appropriate screws or wall anchors.
  • Ensure that there is enough space around the unit for maintenance access.
  • Consider using a protective cover if installing outdoors or in an area prone to dust or debris.
  • If you are unsure about any aspect of the installation process, it’s best to consult a professional plumber or follow the manufacturer’s recommended guidelines.

By following these steps and considering these tips, you can successfully mount your tankless water heater to the wall. Remember to always keep safety in mind and refer to the manufacturer’s instructions for specific guidance related to your unit.

Testing Temperature and Outlet Functionality

Congratulations! You’ve made it through the essential steps of installing a tankless water heater. Now, it’s time to ensure that everything is working perfectly before you can enjoy endless hot showers. Testing the temperature and outlet functionality is crucial to guaranteeing your new tankless water heater is operating at its best.

To test the temperature, turn on your hot water faucet and let it run for a few minutes. Place a thermometer under the flowing water to check if it matches your desired temperature setting. Adjust as needed until you find the perfect balance.

Next, check the outlet functionality by running multiple faucets simultaneously in different areas of your home. Make sure there’s consistent hot water flow without any noticeable drops in pressure or temperature. This way, you’ll be confident that your tankless water heater is providing reliable hot water throughout your household.

Now that you’ve successfully installed and tested your tankless water heater, it’s time to sit back, relax, and enjoy all the benefits it brings. Say goodbye to cold showers and hello to endless hot water! Remember to schedule regular maintenance checks for optimal performance.



How long does a tankless water heater last?

Tankless water heaters are known for their durability and longevity. With proper maintenance, they can last up to 20 years or more, outlasting traditional storage tank heaters by several years.

Are tankless water heaters energy-efficient?

Yes! Tankless water heaters are highly energy-efficient because they only heat the water when needed. Unlike traditional tanks that continuously keep a large volume of water heated even when not in use, tankless models provide significant energy savings over time.

Can I install a tankless water heater myself?

While some handy homeowners may choose to install their own tankless water heaters, it’s generally recommended to hire a professional plumber or electrician for installation. They have the expertise and knowledge required to ensure a safe and proper installation.

Are tankless water heaters more expensive to install?

The initial cost of installing a tankless water heater may be higher compared to traditional tanks. However, the energy savings over time can offset this expense, making tankless models a cost-effective choice in the long run.

Can I replace my existing tank with a tankless water heater?

Yes, it’s possible to replace your existing storage tank with a tankless water heater. However, keep in mind that some modifications may be required to accommodate the new system. It’s best to consult with a professional to determine the feasibility of such an upgrade for your specific situation.

Tankless Water Heater Install: A Step-by-Step Guide

Discover the step-by-step guide to tankless water heater installation. Learn how to install a tankless water heater with ease and save on energy costs.