Water Heater — Install & Repair
Complete guide to replacing or repairing a traditional tank or tankless water heater safely.
Tools Needed
Find Materials Near You
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Instructions
Turn Off Power and Water
Switch off the circuit breaker for the water heater. Turn off the cold water supply valve at the top of the unit.
Drain the Tank
Connect a garden hose to the drain valve at the base. Run hose to a drain or outside. Open the drain valve and a hot water faucet in the house to allow air in.
Disconnect Plumbing
Use a tubing cutter or pipe wrench to disconnect the cold inlet and hot outlet pipes at the top of the heater.
Disconnect Electrical or Gas
For electric: disconnect wiring at the junction box. For gas: turn off the gas valve and disconnect the gas line and flue vent.
Remove Old Unit
Have a helper assist — tanks are heavy. Use an appliance dolly to move the old unit out safely.
Position New Heater
Roll new unit into place. Ensure it sits on a level surface and meets local code for clearances and seismic strapping if required.
Reconnect Plumbing
Connect the cold and hot water lines using dielectric unions to prevent corrosion. Wrap all threaded fittings with Teflon tape.
Reconnect Power or Gas
For electric: connect wires matching colors and secure in junction box. For gas: reconnect gas line and test all joints with soapy water for leaks.
Fill and Test
Open cold water supply and let tank fill completely before turning on power. Check for leaks at all connections. Set thermostat to 120°F.
