If your water heater is beginning to leak, or if it’s no longer producing enough hot water to meet your needs, it may be time to replace it. The average water heater has a life expectancy of 10 to 12 years. But is it really a do-it-yourself type of job?
Water heater installation is usually best left to a professional. First of all, it requires that you physically remove the old water heater and install a new one, which isn’t for everyone. In addition, hiring a pro ensures that the gas, electrical and other connections are all handled safely. The work may also require you getting a plumbing permit from the city or county before getting started. We’ve put together some helpful information outlining the work that goes into installing both gas and electric water heaters, so you can make an informed decision.
Gas water heater
For a gas water heater install, the gas to the water heater needs to be turned off. The installer then shuts off the main water supply and drains the lines by opening a faucet on the lowest floor. A garden hose is then connected to the drain valve to drain out the water left inside the tank (the water may be scalding hot).
The installer then disconnects the gas line using two pipe wrenches – detaching at the union fitting if the pipe is galvanized, or at the flare fitting if the gas supply line is copper. They then disconnect the water lines above the tank and remove the screws connecting the vent to the water heater. It’s important to check the flue for any possible blockage such as bricks, birds and squirrels before installing the new heater. The old water heater is then moved to the side and well out of the space before bringing in the new unit.
An installer sets the new water heater in place in a metal water heater pan – and in a space with at least six inches of clearance on all sides for ventilation. It important to ensure that there’s access to the burner and controls, and to check that the unit is level. The flue is then reconnected to the gas exhaust vent.
Next, the water heater fitting threads are wrapped with pipe dope or Teflon tape. The blue fitting is then attached to the cold water inlet with the arrow facing into the water heater – while the red fitting is attached to the hot water outlet with the arrow pointing away from the water heater. The installer will measure and cut the water line connections to length and reconnect the water line. The risers (water lines above the water heater) need to be 18 inches of rigid pipe before transitioning into a different material. Plastic is not permitted to be connected directly into the water heater if the water heater is fueled by gas.
Connect the gas line. Piping compound is then applied to the threads of the black pipes as they’re connected. Now, the installer must assemble and tighten each fitting, ending with the union fitting. When finished, they open the gas supply valve and turn the water on. It’s important to turn on water at the tank, then turn on one or more hot water faucets to bleed air out of the system. Joints and fittings are then inspected for water leaks.
Next, they test the gas line for leaks by filling a sponge with a mixture of liquid dish soap and water, and applying it to the new fitting. If there's a leak, bubbles will form on the surface and the joint will have to be refitted.
Finally, it’s time to light the pilot and turn on the knob on top of the control box to ignite the burner.
Electric water heater
Installing an electric water heater is similar. It requires shutting off the power to the water heater at the main circuit breaker, then following the same draining procedures as for the gas water heater. When the water heater is drained, the electrical wires are disconnected from the screw terminals under the junction box, and the installer follows the manufacturer's instructions for wiring the new unit. It’s important to adjust the thermostat to the recommended temperature of 120 degrees for optimal hot water production while eliminating the risk of scalding.
Please be mindful of the fact that in 2015, new water heater efficiency standards were put into effect by the federal government. New models may be larger in diameter and even taller than your old water heater. This is because new models are required to be more heavily insulated. Measure the height and diameter of the old water heater and compare it to the new model to make sure it will fit in the space available.
A Roto-Rooter water heater expert can install your new water heater correctly, and help you determine which unit is right for your home, family size and budget. If you do decide to take on the task yourself, make sure to get your work inspected by your local plumbing inspector afterward.