Replacing a Hot Water Heater

Tips on How to Replace a Hot Water Heater

By Mark J. Donovan

The hot water heater is the unsung hero in the home. It’s what allows us to take hot showers. It enables us to wash our dishes and clothes with warm sudsy water. And for some homes, it provides the hot water that circulates through our radiators. Only when a hot water heater fails do we fully appreciate how much we depend upon it. Replacing a hot water heater is fortunately not as difficult as one might think. They are admittedly bulky, however emptied they are not that heavy to carry away. Nor is it too complicated to hook a new one.

Buying a Replacement Hot Water Heater

The first thing you need to do when replacing a hot water heater is to purchase a replacement one. Ideally you should purchase one of the same type and size as the existing one.

This will immensely help speed up the replacement time as you will most likely not have to modify the existing water and electric/gas/oil hookups. Also the venting pipe will also most likely not require modification to connect it to the hot water heater replacement unit. When purchasing a new hot water heater its best to buy it at a plumbing supply store as they typically have the most knowledgeable people that can help you find the exact replacement. Just make sure to write down the specific manufacturer and model number on your existing hot water tank before visiting them.

Hot Water Heater Alternative Technologies

If you plan to hire a plumber to install a replacement hot water heater then you may want to look into more modern alternatives for hot water heaters. Today’s latest hot water heater technology includes on-demand hot water heaters, tankless hot water heaters, solar water heaters, and geo-thermal hot water heaters. All of them can help you save a small fortune on hot water heating bills. Keep in mind that a traditional hot water heater is one of your home’s most energy consuming appliances.

Replacing Hot Water Heater

To replace the old hot water heater, start by turning off power and fuel to it, as well as the water supply source.

Make sure to tape and label every wire or pipe you disconnect from the old hot water heater to enable an easier installation of the new one. Also, you may want to let the hot water heater sit for a couple of hours so that the water in it can cool down a bit.

If you have a gas hot water heater system you may want to call in a service technician from the gas supplier to properly disconnect and cap off the gas line while you do the rest of the hot water heater replacement. You can then call him back when you’re read to have the gas line reconnected.

After disconnecting all the electric/fuel hook ups to the old hot water heater tank, drain the tank by hooking a garden hose up to the drain valve at the bottom of the tank and placing the other end of the hose outside the home. If there is a floor drain underneath the tank simply direct the other end of the hose into the drain. Be careful when draining the water from the tank to not scald yourself, or any delicate plants or vegetation outside the home.

Also, turn on a couple of hot water faucets inside the home to help with the draining process. Ideally you should turn on a hot water faucet closest to the hot water heater.

Replacing a Hot Water Heater

After the tank has fully drained you can then disconnect or cut away the water supply line pipes that feed and exit the hot water tank. You may need a hack saw or a pipe cutter to cut away the old pipes if they are soldered directly into the hot water heater. With the tank emptied and its connections all removed, you and another pair of hands should easily be able to lift and remove the old tank.

To install the replacement hot water heater make sure to carefully follow the manufacturer’s recommendations. In general make sure the new tank is positioned exactly where the old one was. It should sit level and whenever possible have its connections lined up appropriately with the various wires and pipes that will connect to it.

Make the electrical and plumbing connections as appropriate. Make sure to use plumbers tape on any PVC pipes to ensure a leak free system. If soldering / sweating any copper pipes, make sure that all fittings and connections are fully cleaned and fluxed prior to applying heat and solder to the joints. If you have a gas hot water heater, call in the gas service technician to reconnect the gas line.

Once the new hot water heater is fully connected into the home, turn on a hot water faucet nearest the hot water heater. Then turn on the water supply line to the hot water heater tank and let it fill up until water is running freely out of the hot water faucet. This will ensure no air gets trapped into the hot water plumbing system. Then shut off the hot water faucet and turn on the electricity and gas/oil to the hot water heater to have it begin heating water. With any luck you’ve successfully replaced your hot water heater.

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