I was told if I drain my water heater, then refilled the water heater it would help me get more hot water pressure. Now that I have done that, I have even less hot water pressure. The cold water has great pressure. How can I get the hot water pressure back?

Who ever told you that was not a plumber. When you drained your heater was it really a draining or was it flushed? Flushing should be done twice a year for most folks. Test the pressure on the heater drain spigot at the bottom of the tank and come back and tell us if that pressure was strong. Your watyer pressure should be about 45 psi at all faucets.

Bob correct of course. There is a difference in draining and flushing. When you drain, you connect a hose to the drain cock, close the cold water input valve, open a hot water faucet and allow the water to drain out. To flush you connect the hose and open the drain valve, allowing the water in the tank to be forced out by the pressure of the cold water input. You allow the water to run until it is clear.
The pressure of the hot water coming out is caused by the pressure of the cold water coming into the tank. If you have reduced pressure it would be caused by either sediment in the bottom of the tank, or by corroded heat trap nipples on the cold input and hot output pipes.

I was told if I drain my water heater, then refilled the water heater it would help me get more hot water pressure. Now that I have done that, I have even less hot water pressure. The cold water has great pressure. How can I get the hot water pressure back?
When you loose pressure in the hot water line it can usually be traced back to mineral build up. This happens when a water heater is not maintained. The minerals build up to a point where they enter the hot water system and clog the inlet ports of faucet cartridges. I know the other experts have touched on flushing out your water heater but bare with me while I repeat the drill.
For long life and fewer troubles you should keep your heater clear of mineral build-up by FLUSHING NOT DRAINING 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 together the same way you took them out. Don't forget to flush it out every month. Your heater will thank you for it.
Now you're going to hafta go to each faucet that the hot water runs slow in and shut the water off to them and open them up. Remove the cartridge and check and clear the hot water inlet port. Place a pan over the valve and open up the hot water stop to flush out the supply. You should have a strong stream when you do this. If not click back and tell me. Do this with each valve that has a problem. Good luck, Tom

I agree with every one it is good to flush the water heater, the manufacturer recommends once a year, some say two time a year some say every month I do mine every 3 months, also open the link below and watch the video for info only, Thanks.

John




How to Flush a Water Heater - wikiHow (http://www.wikihow.com/Flush-a-Water-Heater)