How Do I Install a Tankless Water Heater?

A tankless water heater provides hot water on demand and runs only when you turn on a hot water tap. It’s therefore very efficient. But any homeowner wanting to switch over from a conventional unit may wonder how to install a tankless water heater. A DIY install is not out of the question. However, you must be prepared and know how to properly set up the system. 

Whether you install a tankless unit yourself or hire a plumber in Troy, MI, here is the general installation process.

Tankless Water Heater Installation Steps

  1. Turn off the Power and Water: Power should be shut at the circuit breaker so there’s no risk of shock while working. The water supply should be shut off as well. Otherwise, you risk flooding your home when working with water lines and making connections.
  2. Drain the Old Water Heater: If replacing a tank-type water heater, drain the system. Start by unscrewing connecting pipes, and then use a hose and bucket to collect the water that drains from the tank. After removing the connecting pipes, remove old wiring and wall-mounting brackets.
  3. Unscrew the Front Cover: With a screwdriver, remove the screws securing the front cover of the new water heater. Be careful not to damage the cover or lose any of the screws. Also be careful with any cables that may connect the cover and the unit, as these may be needed to power an LCD screen or other components.
  4. Mount Your Tankless Water Heater: Place the heater on a wall in an area that’s easy to access. Make sure it won’t be blocked (you may need to quickly access the unit in an emergency). Use the mount and screws included in the package to secure it to the wall, following the steps provided in the instruction manual. 
  5. Install the Pipes: Connect the water pipes to the ports at the bottom of the unit. The package should include an installation diagram that shows their exact location. Stainless steel flexible pipe is best, as it tolerates high temperatures. A PVC-to-copper connection can be used as well.
  6. Install the Flow Valve: The flow valve is installed after making the pipe connections. Simple to install, it enables you to shut off the heater’s water supply if repairs are needed. You can also install a pressure valve at this point if one is required; pressure release valves are installed on the hot water side but can be installed on both sides.
  7. Bleed the System: Before restoring the water supply after installing a tankless water heater, bleed the hot water system by opening all your hot water outlets. This removes air from the system. Leave the water running for a few minutes and then turn the faucets off.
  8. Inspect the Unit’s Electrical Connections: Verify all connections are wired correctly and that each wire is in the correct terminal. If everything looks right, reattach the cover with the screws you removed before. 
  9. Turn the Power On and Test the System: Turn the circuit breaker back on and configure the temperature settings. Don’t select the highest setting as serious burns can result. Check faucets, showers, and other hot water outlets to determine whether the temperature is correct or if any adjustments are needed.

Gas Tankless Water Heater Considerations

If installing a gas tankless water heater, you can fix a tee or valve to an existing line and connect the new supply line to the heater using a black pipe. A copper pipe will be needed to connect old and existing water lines. Use bell hangers to secure the pipes to the wall. The gas supply line must be connected to the shutoff valve, while a vent pipe must link the unit’s vent shaft to an exhaust. These steps require a few tools; unless you’re extremely handy, it’s best to hire a professional.

Electric Tankless Water Heater Considerations

When connecting an electric tankless water heater, make sure to turn off the power and connect a black and red wire to the circuit breaker. Run the cable from the breaker to the heater and connect it to the block terminal on the unit. Every connection must be tight before the panel is closed. A bypassable union connection should be installed on the plumbing line, so you can more easily remove limescale.

Other Considerations When You Install a Tankless Water Heater in Troy, MI

Here are some other important factors to consider during installation:

  • Does your home have enough power to run an electric tankless water heater?
  • What is the water pressure in your plumbing system?
  • Is a permit required in your state to install a tankless water heater?

Contact Hoover Electric, Plumbing, Heating & Cooling

We specialize in high-efficiency tankless water heater installation in Troy, Michigan. Tankless units save space, require little maintenance, and use up to 50% less energy than storage tank water heaters. They can also last up to 25 years. You can trust us for same-day tankless water heater installation and repair, while our technicians get the job done quickly. To schedule service, make your appointment online or call 586-501-8959 today.

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