Water Heater Tips Video
If your water heater fails, there are some helpful tips for the replacement. Be sure you have just one control water shut-off valve on the cold water side. There should not be a valve on the hot water side.
Where the copper pipes attach to the top of the water heater, dielectric unions should be used. When you connect two dissimilar metals, such as copper and iron, in the presence of water, you can get electrolysis. This can cause corrosion of the pipes and eventually a leak. The dielectric union separate the two different metals with a rubber washer. A side benefit of these unions is you can disconnect the pipes quickly with the union's nut.
If you have a gas water heater, the vent pipe must be the proper size to vent the exhaust. If this vent pipe is too small, there will be a backup of the exhaust fumes.
Replace the pressure relief valve when replacing the water heater. Do not try to reuse the valve from the old water heater.
Follow these tips and you won't be in more "hot water" over your installation.