We have an electric hot water heater. Air has suddenly started spitting out of the hot water faucets. I have lifted the relief valve on the water heater but only water ran out of the pipe - no air. No air spits out of the cold water faucets. Any suggestions?

As long as you do not have a leak in the line the air should move out fairly quickly. Open all your hot water valves and let the water run for a few minutes this should remove the air in the lines within a minute or so. A leak should produce water somewhere with all the valves in the off position as the pressure is greater in the lines, but with the water flowing the pressure may be reduced enough to allow air to enter the lines. If the air persists you should look for a leak.

Is your hot water extremely (scalding) hot? If so, you may have a defective thermostat on the water heater causing the water to be heated to boiling temps creating steam, thus the air effect you are seeing. If this is the case, you need to shut the power off the heater NOW and get the unit fixed.