A few months ago we went from well water to city water. We had poor hot water pressure then, but thought it was the well. The hot water pressure has been getting worse. Yesterday I drained the hot water tank (natural gas, I think 1992). I now have good hot water pressure for about 3 seconds and then it is slow going all over again. The water lines are copper throughout the house. I was wondering if there could be something else wrong with the water heater? Also, anyone have pro's or con's on the tankless water heaters? If we have to replace it we have thought about going tankless. Thanks for your help.
-Kevin

Kevin, you don't drain a hot water heater you flush it. Let me show you how.

For long life and fewer troubles you should keep your heater clear of mineral build-up by flushing on a regular schedule. Attach a hose to the boiler drain at the bottom of the tank. With the pressure on, open the boiler drain and let it run until the water runs clear. You will see a spurt of red,(rust) followed by white or yellow grains,(lime or calcium carbonate). This shouldn't take more then a few minutes. Do this monthly to keep it clear. Now flush out your hot water lines on ALL fixtures that are affected . Now pull each aerator and clean the screens. Be sure you put them back togather the same way you took them out. Don't forget to flush it out every month. Your heater will thank you for it. Hope this helps, Tom

A few months ago we went from well water to city water. We had poor hot water pressure then, but thought it was the well. The hot water pressure has been getting worse. Yesterday I drained the hot water tank (natural gas, I think 1992). I now have good hot water pressure for about 3 seconds and then it is slow going all over again. The water lines are copper throughout the house. I was wondering if there could be something else wrong with the water heater? Also, anyone have pro's or con's on the tankless water heaters? If we have to replace it we have thought about going tankless. Thanks for your help.
-Kevin
Thank You speedball1,
I just now flushed it like you said and still have the same problem. Is there any hope for the water heater if it's too late and the mineral build-up has already taken its toll?
Thanks,
Kevin

Verify valves are open all the way. Sometimes on a water heater the hot side will clog at the hot outlet. Simply cut the pipe where a coupling can be used, unscrew from water heater, poke screwdriver in water heater at hot port to break up clog, reinstall piping.