How to Replace a Water Heater

What You'll Need
Pipe cutter
Hand truck
Water heat and fittings

After some years, you might need to replace the water heater since it may start to leak or even stop working completely. However, this job is not as difficult as it first looks and with the use of some proper tools and some experience, it can be a rather easy one. Thus, here is a guide of how to replace a water heater and a list of the required tools.

Step 1 – Remove the Old Heater

Before replacing a water heater, first you need to remove the old one. Start by switching off the heater from the switch and then drain the heater by opening the hot water faucet which will eventually let air flow into the system. In case of a gas water heater, detach the gas line from the heater and cap it. Then use a wrench to disconnect the heater from the water pipes and remove the tank.

Step 2 – Prepare the New Water Heater

Bring the new heater and put it in place. If necessary get some help to load the heater, perhaps with the use of a hand truck. Position the heater so that you can reach its pipeline connections, particularly the vent pipe. In case of a gas heater, install the heater’s draft hood by simply pressing it onto the heater’s top.

Step 3 – Attach the Vent Pipe

Every gas water heater needs a vent pipe attached on the top through the draft hood. However, it is better to use new elbows so that everything will be new and there will be less risk for corrosion. Use small screws to attach the vent pipe with the draft hood and remember that the vent pipe should be standing vertically as far as possible and then horizontally inclined by a ¼ of an inch per foot.

Step 4 – Hot and Cold Water Connections

The best way to make hot and cold water connections is by using copper flex-connectors which you can buy from any hardware store. Use a wrench to fasten the nuts of these connectors from one side with the heater and from the other side with the house water pipes. Covering the male threads with some Teflon tape will certainly help to avoid any leakages.

Step 5 – Use Transition Unions

If the home hot and cold water supply pipes are made up of PVC, it is important to use a pair of transition unions to connect the PVC pipes with the metal threads. However, do not try to assemble the PVC pipes with the heater without the unions since they will heat up and will eventually melt. Finally, switch on the heater and let it warm for about 20 minutes.


Your are now ready to enjoy your newly installed water heater. However, it is always better to refer to a professional technician if any problems develop during this replacement procedure.