Water Heater Replacement - How to Avoid Common Problems and Costly Mistakes

The useful life of a water heater is around twelve years, so sooner or later all it will need to be replaced. Here are some tips to help ensure that your new water heater will safely provide hot water for many years and help you avoid costly and dangerous mistakes.

Comply with all local building codes in effect when installing the new equipment. You should obtain a building permit and have the new installation inspected, but this is seldom done. A qualified and licensed plumber should know and comply with local building codes.

Replace the old equipment with one that is the same physical size and shape, if possible. This will make installing the new equipment much easier. You will avoid or reduce the need to change the location of pipe, power, fuel, and vent connections.

Install the temperature and pressure relief valve (T&P) discharge pipe so that it flows down toward the discharge point. The T&P valve is located on the top or the side of the water heater. It is usually brass colored with a silver colored handle on top. The T&P valve is an important safety device. The discharge pipe must flow down over its entire run so that if the T&P valve leaks, you will know that it's defective and needs to be replaced.

Install at least ¾ inch diameter pipe for the T&P discharge pipe and do not change the pipe size over its run. Use pipe that is rated for hot water such as copper or CPVC. Terminate the pipe no more than six inches above the floor or ground and in a safe place so that someone is not burned if the T&P valve opens. Do not connect the pipe directly into the home's drainage pipes. Leave at least a one inch an air gap between the discharge pipe and the termination point. Missing and improperly installed T&P discharge pipes are a common problem.

Place the water heater in a drip pan made for this purpose if the equipment is located inside the home, and especially if it is in the attic. Install a drain pipe on the drip pan to the outside, especially if the equipment is in the attic or some other place where a leak could cause damage.

Replace the old flexible gas connector, if there is one. Gas connectors are flexible corrugated pipes that are usually silver, brass, or yellow colored. They are usually about twelve to eighteen inches long. Gas connector manufacturers do not recommend reusing old gas connectors.

Replace the cold water shutoff valve, particularly if it is an old gate valve. Gate valves usually have a wheel type handle and look like garden hose valves. Gate valves may seize open and will not close or they may leak with age. It is less expensive to replace an inexpensive gate valve with a better quality ball valve while the plumber is there to install the new equipment.

Replace the flexible water connectors, if used to connect the water heater to the plumbing pipes. Water connectors are flexible corrugated copper pipes. They are not used on all equipment. Replacing water connectors is not required, but replacing them is inexpensive insurance against problems. In places with aggressive water, such as Florida, you should always replace these connectors. Do San Diego water heaters not bend water connectors so much that you reduce the connector's diameter.

Connect the gas vent to the draft hood and to other vent sections with three sheet metal screws. Vents that become loose or disconnected can leak carbon monoxide into the home.

Use dielectric fittings when connecting copper pipe to steel water heater connections. Without these special fittings, the connections may corrode and leak.

Raise the gas burner or the lower heating element on an electric water heater at least eighteen inches above the floor if the equipment is in the garage. This helps avoid igniting gasoline vapors that might be in the garage.

Secure the equipment to the house frame if you are located in a seismic risk area such as California.



Water heaters can provide may years of safe and effective service when properly installed. By using these tips you can ensure a safe installation and you can avoid costly correction of mistakes when you sell your home.