he installation process for adding a tankless water heater on your property will primarily depend on the type of fuel you’ll be using, your existing gas, water, and electricity setups, and the size of your system.

Tankless hot water installations in 5 main steps

There are five main steps to installing an on-demand hot water heater:

  1. Gas/water/electrical setup

  2. Mounting

  3. Attach water, gas, and ventilation

  4. Connect electrical power

Many of these steps differ slightly in how, when, and if they occur from installation to installation based on your system’s fuel type. For example, electrical units don’t need ventilation, so there’s no need to install a ventilation line alongside a water line like you would with a gas unit.

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tankless hot water installation

1. Install necessary gas lines, water lines, and wiring

Before your actual heating unit can be put in place, your installer will need to prep water lines, wiring, and, for gas units, gas lines so they are all ready to feed into your new heating system. For electric units, you’ll may require breaker box upgrades since the heater uses a significant amount of electricity. Importantly, all types of tankless water heaters use at least some electricity to operate the control systems.

2. Mount your heater

Next, your installer will mount the actual heating unit. Due to their small size, tankless hot water heaters can be installed on most flush wall surfaces, as long as they have access to fuel and water lines (which should already be taken care of).

3. Connect water lines, plus gas and ventilation lines for gas units

Your installer can connect all the necessary inputs after your on-demand hot water heater is in place. This means hooking up water lines and, for gas units, tying in the gas line and a ventilation system to remove exhaust fumes from burning gas for heating. Electric tankless hot water heaters don’t need a gas line or ventilation, but will still need a water line hookup.

4. Connect to electrical system

Finally, your installer or electrician can connect your new tankless water heater to your home’s electrical systems. Once the system is all hooked up and properly tested, you’re ready to start using your new water heating system.

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