Before You Begin
Determine whether you need a water heater replacement or if maintenance will suffice. If you’re not getting hot water, it could be the heating element or another maintenance issue. Take a quick maintenance assessment before embarking on a full replacement.
If you have water on the floor or on top of the unit (this is different from water leaking from a supply line above the unit), you’ll probably need a new water heater. The data plate on your current tank has size and energy specifications that help make buying a comparable unit easier. If your family has changed size, it’s a good time to consider upsizing or downsizing your electric water heater.
Check local building codes before you get started to ensure compliance. If you’re not comfortable with water heater installation, call a pro.
Water Pressur
Your home’s water pressure is important for all water-using appliances. Reduced pressure lessens stress on plumbing lines and extends the life of appliances and fixtures.
Check your home’s water pressure using a pressure gauge on your outdoor spigot. 50- to 60-PSI is ideal. If your home’s water pressure is greater than 80-PSI, lower it with the pressure-reducing valve at the main water shut-off.
You may want to consider an inline pressure gauge for pressure monitoring. If your home doesn’t have a pressure-reducing valve, a pro can install one for you.
Expansion Tank
Determine which expansion tank you’ll need. A thermal expansion tank alleviates excess pressure in the lines of a closed system. A 2-gallon expansion tank works with water heaters up to 50 gallons. Use a 5-gallon expansion tank for water heaters up to 100 gallons. Check the manufacturer’s recommendations for exact sizing.
The expansion tank installs to the cold-water supply line near/above your water heater. You can install an expansion tank using push-fit fittings. They slide into the pipe; no soldering is needed. If you decide use solder fittings, de-burr the pipe and fittings, and clean them. Apply soldering paste to both the pipe and fittings, and assemble. Heat the fitting and then solder the connection.
Electric water heater installation requires that the expansion tank pressure match the main water pressure to work effectively. Use a hand air pump to increase pressure or depress the valve to lower it.