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How to Install a Point-of-Use System

Learn how to have instant hot water at every faucet by installing a point-of-use system in the home.

More in Plumbing

install a point of use system
  • Time


  • Price Range

    $500 - $1,000

  • Difficulty



Step 1: Calculate Wasted Hot Water

A point-of-use water heater has a built-in thermostat with auto shut-off so it doesn't run when it reaches the desired temperature. This system has a small tank that mounts under the sink, which holds the hot water unit it's needed.

Before installing a point-of-use system, time how long it takes to fill up a one-gallon bucket using a faucet at the greatest distance from the water heater. Next, record the time it takes to get hot water. Multiply the two numbers together, then multiply that number by 10 (average number of uses per day). This will give the number of gallons wasted every day waiting on hot water.

Step 2: Prep for Installation

Note: Be sure to follow the local plumbing codes before installing a point-of-use water heater.

Clean out the area under the sink if needed.

Next, shut off the water under the sink. Turn off the electricity to the area at the breaker.

shut off water under sink

Step 3: Remove the Water Lines

Note: Use pressure relief valves and drip legs to run this system safely.

Using an adjustable wrench, loosen the nut around the hot water stop.

Remove the line from the valve. Loosen the line running from the faucet using slip-joint pliers, then remove.

loosen nut around hot water stop

Step 4: Attach Stainless Flex-lines

Attach stainless flex-lines to the faucet connection; tighten the connection using a wrench.

Next, attach another flex-line to the hot water angle-stop and tighten.

Place the tank under the sink.

attach stainless flex lines to faucet connection

Step 5: Connect the Lines

Attach 1/2" to 3/8" flex-line from the hot water line to the cold water intake on the tank.

Using a 1/2" to 3/8" flex-line, connect the faucet to the hot water connection on the tank.

connect the hot and cold lines

Step 6: Finish Installation

Turn the water and power back on. Next, check the area for leaks.

Turn on the faucet to purge the air from the water line.

Plug the point-of-use system in under the sink. If a plug is not installed, have an electrician install one.

Set the desired temperature on the system.

set desired temperature on system