Little hot water pressure in shower & almost no hot water in laundry?

Roughly 10 years ago, the hot water going to the wash machine went to a dribble. I asked a plumber about it and he just shrugged. I took the valve apart and couldn't see an issue. No big deal as I don't mind using cold to wash clothes.

More important to me is the shower. Roughly 3-4 years ago, the hot water pressure would come and go. Some times it would be high and other times low. We've been having issues with our water heater (so much sediment that I couldn't drain, burned out elements) so I assumed the shower pressure had something to do with that. I installed a new water heater yesterday and the pressure is still low. The cold water is fine in the shower...and there's plenty of pressure in the bathroom sink...and everywhere else in the house (except laundry), cold and hot.

The shower faucet was replaced by a plumber ~15 yrs ago. I've attached a photo.

Any ideas what could be going on?

remove the trim and post another picture.
Possibly a PricePfister but not sure.
I don't think it's a Moen Positemp because the lower right cover plate screw is on the wrong side. does the handle tilt up and to left for hot and right for cold OR do you turn it counterclockwise from cold to hot

pressure balance cartridges can get stuck preventing the hot from flowing properly.

?? copper or galvanized steel piping?? OR??

Mr_David said:

remove the trim and post another picture.
Possibly a PricePfister but not sure.
I don't think it's a Moen Positemp because the lower right cover plate screw is on the wrong side. does the handle tilt up and to left for hot and right for cold OR do you turn it counterclockwise from cold to hot

pressure balance cartridges can get stuck preventing the hot from flowing properly.

?? copper or galvanized steel piping?? OR??

Click to expand...

Sorry. I should have said. It's an American Standard faucet...and yes, it tilts up and to left for hot and to right for cold. I can still take a pic. Just let me know.

I don't know what the spigot is. It was in the house when we purchased it in 1989.

Re the piping, I don't know. We have a concrete slab floor. However, what I do see under the sinks and going to the shower has all been copper. There were a couple galvanized couplings on the old water heater and I noticed they were quite corroded on the inside.

Looking forward to hearing your thoughts. Thanks!

Update. The pressure is definitely lower now that I put the new water heater in. Just got out of the shower and it was barely enough to come out of the head.

I'm fairly certain this issue is some how connected to the water heater. I now recall experiencing really low pressure after changing it last time in 2008.....or, after replacing the thermostat.

I couldn't drain the old tank so had to wrestle it outside with a hand truck. I then drained it alternating between draining out the side, top, and bottom. The water is mostly out now but it feels and sounds like the tank is 1/3 to 1/2 full of sediment. Could some of this sediment have gotten into my faucet somehow? But why would the pressure be so much lower now with the new heater?? Baffling.....

Try Replacing the valve cartridge. It has a balance spool that might be stuck.

OR

Sometimes the dip tube on an old heater fall apart and you get small pieces of plastic stuck in the port to the valve cartridge. remove the valve cover and see if you have integral stops on the shower valve..

IF NO the just turn off water to house, Pull the cartridge and check for debris.

If you do have stops try this

Turn off the cold one.
Stuff some rags in the wall to keep water out of wall.
Turn off water to house.
pull the shower cartridge.

##Turn water to house back on for a moment.( cold stop is off)
how's the flow coming out of the hot side ( main valve cartridge removed )?
still low?
turn off house water.
remove the integral stop stem (maybe order some replacements just incase there is an issue with them )
repeat ##

Mr_David said:

Try Replacing the valve cartridge. It has a balance spool that might be stuck.

OR

Sometimes the dip tube on an old heater fall apart and you get small pieces of plastic stuck in the port to the valve cartridge. remove the valve cover and see if you have integral stops on the shower valve..

IF NO the just turn off water to house, Pull the cartridge and check for debris.

If you do have stops try this

Turn off the cold one.
Stuff some rags in the wall to keep water out of wall.
Turn off water to house.
pull the shower cartridge.

##Turn water to house back on for a moment.( cold stop is off)
how's the flow coming out of the hot side ( main valve cartridge removed )?
still low?
turn off house water.
remove the integral stop stem (maybe order some replacements just incase there is an issue with them )
repeat ##

Click to expand...

Thanks. Appreciate your help!

I can't get the stink'n handle off though. I figured after the set screw came out, the handle would simply pull right off. Nope. The set screw is all the way out of the threads...but it came off the allen wrench and is now floating around in the handle. Still seems like the handle should just pull off. I've tried pulling with some force....and I've tried levering it off carefully with a claw hammer. Nothing. I've looked at the American Standard PDF installation instructions...and still can't figure it out! What am I missing here?

Ok. I poured some boiling hot vinegar on it...and pried the handle off. Now, I'm trying to get the cap off behind that. It's stuck good too!

try some PB blaster or liquid wrench. just a little bit. It will come off.

Boiling water !! Nice trick. never tried that before

Mr_David said:

try some PB blaster or liquid wrench. just a little bit. It will come off.

Boiling water !! Nice trick. never tried that before

Click to expand...

Thanks! But it wasn't boiling water. It was boiling vinegar!

At any rate, I'll spare all the details other than to say that I'm embarrassed to admit that I spent the better part of the day working on this....now know it's a 15 minute job. A rubber washer had somehow found its way into the opening of the cartridge....presumably from previous work on the water heater several yrs ago. I'm guessing that it wasn't lodged in good, came out a little during the draining the other day then relodged itself in better. Looked like a black work hanging out of the back end of the cartridge.

Was so happy to see that I had full pressure again. The bad news is that for some reason, the cartridge is leaking now. I've tightened it as tight as I can get it and it still has a slow drip.

The model number was placed on a sticker on the cartridge. Didn't think to write it down before the boiling vinegar took it off! So, I'm hoping some photos will be enough for the folks at American Standard to identify for replacement parts. Or, perhaps I should just replace the entire cartridge given that it's ~15 yrs old. Thoughts?

I'd replace it for another 15 years of problem free service.