It depends on what type of water heater you have. If it is a water storage heater (tank type) then yes. There is a valve at the top side of the water heater with a little easing lever on it. This valve is called the temperature and pressure relief valve and should be operated annually to ensure it is still working. Just pull the easing lever up for a few seconds and then release. Water should drain from the pipe. There are checks and tests that can be done but these must be attended to by a licensed plumber. Give Lamb and Bell Plumbers a call.