out of the blue I lost pressure on the hot water throughout the house. I have drained and flushed the water heater which is 12 yrs old and was fairly clean. If you use one devise at a time the pressure is ok but not like before, however if you turn on more than one faucet, bath or shower the pressure goes to very little or none. i was told when i bought the house that it has rolled plumbing throughout if that matters. I've tried running hot and cold at the same time (cold has awesome pressure)I have even plug some fixtures and opened one then turned the hot on in the plugged fixtures and nothing. Does anybody have any other suggestions before I call a plumber? No new fixtures add and all valves are fully opened.

Replace your water heater if it is 12 years old....it has in all probability run its life span. After the new one is installed and all the air has been vented from your system your pressure should be back to normal.

the heater most likely has some sort of heat trap nipples at the H&C connections. it is possible one or both are clogged ?
try this.
run a garden hose from a faucet to the heater location.
use a washing machine hose to connect the garden hose to the drain valve on the heater.
turn it on all the way and open the drain valve to feed what you know is full pressure into the tank.
take off a faucet aerator and open the hot side to see what happens.
this is step one of trying to figure out what is happening.
heat trap nipples pictured below.

one last question.
did this happen slowly or abruptly ?

abruptly, I followed your instructions and there is no change in pressure any other suggestions?



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well that eliminates any problem with the incoming cold water.
next step is to figure out if the hot water outlet nipple is clogged.
this of course means cutting a pipe to have a look-see at the nipple.
I would turn off the cold water to the heater, drain some water from the tank, cut the hot outlet pipe about 1 1/2 inches above the tank, cover the top with a big towel and briefly turn the cold back on.
you will know immediately if there is pressure or not.
if you have no pressure then the problem is at the tank outlet.
just how much you want to get into this procedure is up to you.
you can put the pipe back together with a sharkbite coupling to restore your hot water.

I have to apologize apparently I had a kink in a non kink hose so I reconnected and the water pressure was restored with one exception being when you turn the bath on in the master you lose pressure everywhere. I did disconnect the copper flex from the top of the water heater leading to the hose and did not see blockage. I did not check the cold water inlet valve. I checked the cold water inlet and of course it was plugged by some small rocks and a piece of plastic. Thank you packy for all your help



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