I have plastic plumbing throughout my house... in the bathroom right above the hot water tank the hot water pressure is fine... in the bathroom halfway across the house it drops a bit... maybe 25%... in the kitchen all the way across the house from the water heater it drops drastically... probably an 80% drop in pressure. I have drained the sediment from the tank and also cleaned the aerators in the faucets. Any idea what is causing this? The main line is 3/4 inch and the sink lines are 1/2 inch. Thanks in advance for any responses.

Are you sure all the valves in the system are fully open betweent the Water heater and the Kitchen Faucet? There should be at LEAST on unde rthe sink... and I would be surprised if there isn't another closer to the water heater.

I am assuming in the absense of information to the contrary, that the cold water pressure is fine everyplace.

Smoothly - Thanks for the response. All the valves are wide open between the water heater and sink. I was able to follow the pipes downstairs into the basement all the way back to the water heater. At one of the junctions I noticed some white buildup. Calcium no doubt. I took my wrench and gave it some serious taps. I saw some big chunks float away towards the kitchen sink. Well the pressure still hasn't improved. I tried to trace the pipe and tap every junction between the heater and sink. Still no luck. Not sure what to do if it is just a clog from buildup.

Cold water pressure is great everywhere.

I have plastic plumbing throughout my house.
Does that mean you have CPVC piping?


I saw some big chunks float away towards the kitchen sink. How could you do that? How can you see inside a pipe?

A build up of anything around a joint indicates a leak at that joint.

Water pressure and volume of hot and cold at each faucet should be equal or nearly equal. A significant difference indicates a restriction of some kind.

What kind of faucets do you have, single handle or two knobs?

Suggestion, remove hot stem or cartridge at kitchen faucet. Hold a cup over opening and turn of water briefly to flush line.

Alternative suggestion, if you have flexible supply lines to faucet, switch hot to cold and cold to hot. If the reduced pressure and volume moves to cold that would indicate a restriction in the hot side of the faucet.


I have drained the sediment from the tank
Does that mean you drained the tank or does it mean you flushed the water heater? There is a difference.

How old is water heater?

OK so I have fixed the issue. hkstroud - you were right on. There was a restriction. I have pex pipe. The pipe in my house is not clear but off white but I could still see through it with a flashlight on the other side. I was able to locate some calcium build up at a junction, so I tapped the fixture and saw some white deposit float away. Well I tracked the hot water line all the way to the sink, low and behold the 2 inch segment of pex pipe from the shut off vavle under the sink to the wall looked different. When I shined my light behind the pipe it almost looked like glass shards. I got brave and sawed the 2 inch piece, and tons of little white chunks of calcium were blocking the valve and pipe, I would say about 90% blocked. Anyway got the proper tools, cleaned it out and replaced. The water heater is the houses original 1996. So 18 years old. Is there anything I can do to prevent calcium from building up and clogging my sinks and such? Thanks for the replys.

It was a single handle faucet and I drained the tank thinking there might be a sediment issue with the tank causing a blockage in my pipes.

Congratulations:
Very smart to use the light to see whats going on inside the pipe. Didn't know you could do that.

Draining a water heater is when you turn off the cold water input valve, open the drain valve, open a faucet and let the water drain out. Flushing a water heater is when you leave the input valve open, open the drain valve and let the water, under pressure, flush out the tank. Let water run until it is clear. You should flush not drain.

What you describe sounds more like the remnants of a deteriorated dip tube than calcium or mineral build up. Suggest replacing dip tube. While you are doing that, you probably should also replace the anode rod.