There are many home improvement tasks that are intimidating. One that does not need to be as intimidating as it might sound is to change out a hot water heater. This job can cost anywhere from $150-$300 or more if done by a professional plumber or “box store” installer. You can do it yourself for around $50. If your hot water heater kicks the bucket, here is what you can do to change the
The first thing that you need to do is find a suitable replacement for your now non-functioning unit. Make sure to find one that is about the same height as the one that you are replacing. All the hookups should be very similar, but you will want to make sure that your new unit will fit the plumbing that is currently in your home. If you have a short tank, and buy a regular or tall tank, then you will have to redo most of the plumbing to make it work. Once you have a new tank on hand, you are ready to start removing the old, and installing the new.
First, turn off the cold water supply line entering the tank. Turn off gas supply at the valve that should be at the tank. If there is no valve, turn off gas at main valve entering home. Then connect a garden hose to the spigot at the bottom of the tank. Turn the spigot on to drain the tank either outside or down a drain. When the tank is empty, you can begin disconnecting all the fittings connecting the tank to gas lines and water lines.
There should be one gas line that enters the front of the water heater. There will be two fittings that need to be removed, and kept for the new tank. The first connects the line into the second fitting, which is inserted into the water heater itself.
There are two lines that will come into the top of the water heater. One is the cold water supply, the second is the hot water line. Both should be labeled and identified on the top of the tank. Both must be removed. You may be able to disconnect these fittings with a pipe wrench. However, if the line is copper, which has been sweated, you will have to cut the line, and reinstall. Be careful to only cut what you need, and do not cut behind the water shut off valves! Most of this line should be ½ inch copper. Finally, you can remove the vent pipe from the top of the tank. Be careful not to damage the vent pipe, so that you can use it for the new tank.
Once both of the water lines, and the gas line is separated from the old tank, it can be removed. If you have a metal recycling plant near you, you can sell this tank for scrap.
Next, set the new tank into the vacant spot, making sure to put the temperature gauge and pilot light window in the front. Then you can hook up the cold water supply line, and the hot water line. There are a couple of ways to do this, depending on how much space you have and the quality of the plumbing you have after disconnecting the old tank. You can use a braided stainless steel line to connect the tank to the water supply. To do this, you will need to have a compression fitting with male threading to accept the female adapter from the braided line. Another option is to use copper pipe with all compression fittings. If you have plenty of space the first option may be best. But, if you have tight spaces, then you will want to use the second option.
Next, you can hook up the gas line. First take the adapter removed from the old tank, and insert it into the regulator on the new tank. Then, connect the gas line to the tank. Do not turn on the gas at this time. The tank must be filled with water before lighting the pilot.
Hook up the vent pipe to the vent cap that should come with the tank. If the tank is the same height as the one you are replacing, this should be very easy. If you have to change sizes, then you may have to add to the vent pipe (for a shorter tank) or cut the vent pipe (for a taller tank).
Now that everything is hooked up, you are ready to fill the tank. Turn on the cold water supply and check to make sure that there are no leaks in any of the new fittings. Make sure the hot water line is also open. You will want to open all the faucets in the house, and release all the air in the lines. When all the faucets run without sputtering, your tank is full. Of course, the water heater is not turned on yet, so the water will be cold.
Next, turn on the gas to the tank. You should use a soapy water mixture to test for gas leaks in all of your fittings. Sponge the solution onto the fittings, and watch for any bubbles. If you see any bubbles, make sure to turn off the gas, and retighten the fittings. If there are no leaks, then you can follow the instructions found with your tank to light the pilot. Once the pilot light is lit, then you can set the thermostat to a safe level.
Changing a hot water tank is not nearly as difficult as many people may think. However, make sure that you have all the tools on hand to get the job done, or you may spend more time running errands than actually getting the tank installed. If you have any doubts about whether you can do this job yourself, you can always have your new tank installed by a professional!