Replace an older tank-style water heater with an energy-efficient tankless model is an invaluable home upgrade, but requires special skills, tools, and permits before being attempted. So learn how to install tankless water heater here.
This guide will provide all the knowledge and advice necessary for installing tankless hot water. Covering both gas and electric models, it outlines each step so you can decide if you want to undertake the installation yourself or hire an installer for tankless hot water installation.
Installation: A Detailed Overview
Installing a tankless water heater requires more preparation than replacing an old unit, since you are making significant upgrades to your home’s infrastructure. Therefore, conducting extensive research and preparation are crucial. When installing one you must deal with water, gas, and electricity -each subject to strict local building codes for safety considerations.
An essential element of a successful tankless installation, in comparison to traditional tanks, is having larger capacity utility lines available. Since a tankless unit heats water only when needed, its energy demands increase quickly requiring larger gas lines or heavier electrical wiring than your old tank had required. Before beginning this project it is wise to check with your local jurisdiction as this project represents major home improvements that require permits before getting underway.
Advantages of a Tankless Water Heater
Choosing to install tankless water heaters offers several important benefits over traditional storage tank models. These advantages often make the initial higher cost worthwhile in the long run.
- Endless Hot Water: The biggest benefit. Since the unit heats water as it flows through, you will not run out of hot water. You can take long showers or run the dishwasher and laundry at the same time without worrying about a cold surprise.
- Greater Energy Efficiency: Tankless heaters only use energy when a hot water tap is on. A traditional tank constantly heats and reheats a stored supply of water, wasting energy. This efficiency can save you a good amount on your monthly utility bills.
- Space Savings: These units are small, usually about the size of a suitcase. They mount to a wall, freeing up significant floor space compared to a bulky storage tank. This is a huge plus for small utility rooms or closets.
- Longer Lifespan: With proper maintenance, a tankless water heater can last up to 20 years or more. This is double the average lifespan of a standard tank-style heater.
- Reduced Risk of Water Damage: Since the unit does not store large amounts of water, there is no risk of a tank failure leading to a basement-flooding catastrophe.
Before You Begin: Important Things to Consider
Proper planning is the most important step for a successful tankless water heater setup. Skipping this section can lead to major headaches and added costs later on.
1. Sizing: Get the Right Flow Rate
Tankless heaters are measured by flow rate, in gallons per minute (GPM), not by tank size. You must choose a unit that can meet your home’s peak hot water needs.
- Peak Demand: Think about how many hot water appliances you run at the same time. This could be one shower (2.5 GPM), a sink (1 GPM), and the washing machine (3 GPM). Your total need is 6.5 GPM.
- Temperature Rise: The flow rate listed on the box drops as the incoming water temperature gets colder. If you live in a cold climate, the unit has to work harder to raise the water temperature, which lowers its GPM output.
- Expert Advice: If you are unsure, talk to a qualified plumber to help size the unit. A correctly sized unit is essential to avoid running out of hot water when you need it most.
2. Location and Clearance
Choose a non-freezing location close to the main gas or electrical supply and the most-used hot water taps.
- Service Access: Manufacturers require a minimum of 12 inches of clear space around the unit for maintenance and service.
- Outdoor Units: Some models are designed for outdoor tankless installation, which can simplify venting but may require anti-freeze kits in colder areas.
3. Permits and Codes
Never start a water heater installation without checking with your local building department.
- Required Permits: Most areas require permits for plumbing, gas, and electrical work. This ensures your tankless hot water install is safe and follows all local building and safety codes.
- Inspections: An approved permit means a local inspector will check the work. This protects your home and often keeps the product warranty valid.
Uncertain About the Best Water Heater for You?
The choice between a gas and an electric model is a big one. It mostly depends on what your home currently uses and the upgrades that would be needed.
Gas Tankless Water Heaters
Gas models use natural gas or propane. They are generally more powerful and can handle higher GPM demands than electric models, making them a good choice for larger families.
- Gas Line Upgrade: You will often need to increase the diameter of your gas line. Traditional tank water heaters use a smaller line than the high-demand gas tankless unit.
- Venting Requirements: Gas units create exhaust fumes, including carbon monoxide. They must be properly vented to the outside using specific, approved materials.
Electric Tankless Water Heaters
Electric models use powerful heating elements. They are a good option for homes without an existing gas line or for “point-of-use” applications like a sink far from the main heater.
- Electrical Service Upgrade: Electric units require a massive amount of power. Many homes need a major upgrade to the electrical service panel to handle the dedicated high-amperage circuits the unit requires.
- No Venting Needed: Since there is no combustion, electric models do not require a complex venting system.
Step-by-Step: How to Install an Electric Tankless Water Heater
This is a general guide. Always follow the specific directions in your unit’s owner’s manual.
- Safety First: Turn off the circuit breakers for the old water heater. Turn off the main water supply to your home.
- Remove Old Unit: Drain the old tank using a garden hose attached to the drain valve. Disconnect the water lines and electrical wiring. Dispose of the old tank properly.
- Mount the New Unit: Use the included template to mark the wall. Securely mount the small tankless unit on a firm wall using appropriate screws and anchors.
- Connect Water Lines: Attach new cold-water inlet and hot-water outlet lines. Install a manual shut-off valve on the cold line and the required isolation valves for maintenance.
- Connect Electrical: Run the dedicated, high-amperage wiring from your main electrical panel to the unit. Connect the wires to the terminal block inside the unit, matching color codes and ensuring the ground is secure. Put the cover back on.
- Test the System: Open a hot water faucet to bleed air out of the pipes. Once water flows smoothly, turn the circuit breakers on. Set your desired temperature and check for leaks in the water lines.
Step-by-Step: How to Install a Gas Tankless Water Heater
Gas units have the added complexity of the fuel source and the venting system.
- Safety First: Turn off the gas supply at the main valve. Turn off the water supply to your home.
- Remove Old Unit: Drain and disconnect the old tank. Properly cap or seal the old gas line and water lines.
- Mount the New Unit: Secure the new tankless unit to the wall in its chosen location.
- Install Venting: This is a crucial step. Install the approved venting material (stainless steel or PVC) from the unit to the outside, following the manufacturer’s maximum length and elbow guidelines. Ensure the system slopes slightly to allow condensation to drain if you have a condensing unit.
- Upgrade and Connect Gas Line: If needed, upgrade the gas pipe to the correct size. Install a new gas shut-off valve and a sediment trap before connecting the line to the unit.
- Connect Water Lines: Similar to the electric model, install the cold and hot water lines, isolation valves, and the required T&P relief valve.
- Test for Leaks: Turn the water supply back on and check all water connections. Use a commercial leak detector or soapy water on all gas connections. Bubbles mean a leak. Shut off the gas and fix any leaks immediately.
- Power and Start-Up: Connect the small electrical power source needed for the unit’s computer and fan. Turn on the gas. Run a hot water tap to purge air, then follow the manufacturer’s start-up sequence to fire the unit and set the temperature.
You can read about: How Long Does a Tankless Water Heater Last?
Find A Local Water Heater Professionals
If you’re thinking about installing a tankless water heater, think again – this isn’t a simple do it yourself project. So much is involved – gas lines, electrical lines at high voltage, plumbing and appliances – and if things go wrong, serious problems will result. Faulty water heater installation can also void the warranty on the unit, or possibly even affect your home insurance coverage, and could lead to expensive repairs if things go wrong later.
For less hassle and peace of mind, contact the professionals at Derks Plumbing. Our licensed and insured plumbing technicians specialize in Tankless Water Heater Installation Eagle Rock homeowners can trust. They will ensure the installation meets all local building codes and they will safely and easily perform any gas and electrical upgrades that may be necessary.
Conclusion
A tankless water heater is a convenient and modern upgrade that provides endless hot water while saving money on your energy bills. When done correctly, installing a tankless hot water heater can be done without the use of a water heater tank. An effective installation of a tankless hot water heater starts with planning which includes some knowledge of local codes, plumbing, gas, and electrical systems.
Whether you choose to complete the project yourself or hire a plumbing or gas professional to help you, knowing how to install tankless water heater will ensure you enjoyment of your investment for years.
FAQs
Q: Do I really need a permit to install a tankless water heater?
Yes, almost all local governments require permits for work that involves gas lines, major electrical changes, or plumbing modifications. Getting a permit ensures the tankless water heater installation is safe and passes official inspection.
Q: How long does a tankless water heater installation take?
Replacing an old tank with a new one usually takes 3 to 4 hours. Converting from a tank to a tankless unit, which often requires major gas or electrical upgrades, can take a licensed professional a full day, or sometimes two days, depending on the complexity of the required infrastructure changes and venting.
Q: Can I use the old vent pipe for my new gas tankless water heater?
No, you cannot. Gas tankless water heaters require special venting. They use power venting and need an approved material like Category III stainless steel or PVC. The old chimney or vent is not safe or code-compliant for the new unit. Tankless water heater venting must use the material specified in the unit’s manual.
Q: Why is the electric tankless installation more complicated than I expected?
Electric models require a good deal of power. The larger challenge is that they frequently require multiple, separate, 240-volt circuits to provide the required power. This can mean expensive new work and upgrades to the electrical service panel for your home. The wire in the walls is typically too small and not capacity rated for the equipment load.
Q: What is the most important thing to remember for a successful tankless hot water install?
Proper sizing of the unit is the most important factor. You need to match the unit’s flow rate (GPM) to the actual hot water demand of your home. If it is too undersized, you will find yourself with lukewarm water when you have multiple fixtures running. If you keep your sizing in line with performing any necessary utility upgrades to install to your home, you are on your way to a happy tankless hot water install.
