Slowly reduced how water flow

[koreywill]

Hello! First time poster here. My wife has noticed over the last month or so that she's getting less hot water flow at the tub. It's a single handle Delta faucet with no thermostatic mixing valve. Turn left for more hot water and right for more cold. Simple. The house is 37 y/o and, we had it re-piped with Pex about 10 years ago because the original poly butyl was breaking down. Every fixture in the house has a flow restrictor of some type to keep flow at 2 gpm or less. But not the tub. That used to crank out the water like crazy. It still does on the cold side but noticeably less on the hot. I took the faucet apart and found no obstructions of any type in the water pathways.
The water heater is 12 years old and is probably due for replacement. There is a 9" piece of galvanized pipe that comes out of the hot water outlet and then connects to the pex. We have a medium to high calcium/lime density or hardness water system - not a well.
Is it possible that after 12 years the calcium has built up inside that short piece of galvanized pipe to restrict the wide open flow at the tub? All the other outlets are seemingly unaffected (hot and/or cold) because they all have a low flow rate any way.
And, if that is the case, does it make sense to just replace the 9" galvanized piece and hope for the best or just bite the bullet and replace the water heater anyway?
Thanks for any ideas and suggestions.

 

[Geofd]

Changing that galvi can only help but maybe pull the delta cartridge and soak it or change it, you could also clean were the water enters for hot and coldits possible there could be build up

 

[koreywill]

Already changed out the old cartridge with a new repair kit and it didn't help at all. Had water turned on while cartridge was out. Full force from cold but about half the flow, if that, with the hot.
Are you suggesting clean the cold water inlet at the top of the water heater?

 

[Twowaxhack]

Replace the galvanized nipple with a brass nipple.

The galvanized nipple has probably started to close up from rust.


Sitting here, I’d bet the house that’s your problem.

 

[Geofd]

Already changed out the old cartridge with a new repair kit and it didn't help at all. Had water turned on while cartridge was out. Full force from cold but about half the flow, if that, with the hot.
Are you suggesting clean the cold water inlet at the top of the water heater?

No now that you've checked the cartridge change that pipe

 

[koreywill]

Maybe the picture will show the setup better than me trying to explain it. There are crimp connectors and don't have the bands or the tools to redo those if I separate the joints. I don't know the mechanics of how the brass nut holds the pex to the galvanized pipe coming out of the water heater so I'm afraid to turn that at all. Has anyone seen this type of setup? If so, what can I do next to check the galvanized pike for a blockage without creating a worse problem and ending up with no water.

 

[Twowaxhack]

If you have good hot water flow everywhere except the tub then your water heater isn’t the problem. The problem would be in the tub valve or the single hot pipe to it.

 

[koreywill]

I would agree with you except all the other outlets have flow restrictors on them of 1 1/2 to two gpm. The volume of water for each of those is completely different than the tub. I did change the valve parts out for brand new and there was no difference - cold still ran like it used to and the hot was maybe half as much when it used to be the same. After taking the new parts out I I ran a stiff wire as far as I could into the hot and cold delivery side. I could not feel any obstructions.

 

[Twowaxhack]

Take it apart and see

 

[koreywill]

Twowaxhack: Believe me, that's what I want to do but, not having the right tools to put it back together again, would leave me without any running water in the house. I've never worked with PEX before so I have no knowledge of what to do with it or how to do it.

 

[Twowaxhack]

Turn on all the other faucets at once and see if you get a combined flow greater than the tub flow. You might have to catch the water and use a stop watch to be accurate.

If you do get more combined flow out of the other faucets then it’s not the water heater outlet.

You know it could be the inlet to the water heater, not just the outlet. It could be either or both. Make sure the stop valve at the water heater is fully open.

You could check the inlet flow by connecting a hose to the drain and opening or by operating the relief valve. Be advised…….if you disturb either one, it may have to be replaced. That’s the risk you take during diagnostic work.

 

[koreywill]

Well, it was a simple solution. Took the galvanized fitting out (supply to the house) and the pipe was a little rusty but that's about it. No blockage. So, took the input side off, looked down into the hole and couldn't see much at all. Realized I was looking at the plastic dip tube. Pulled that out and the water stayed in the top of the tube and it was heavy. Took it outside, tapped it gently on the bumper of one of the vehicles, and lime/calcium particles started coming out. There were three or so solid pieces that came out. Finally got it emptied out and put it all back together. All is good.
Great ideas and great suggestions and I thank you all for the input. Maybe that problem will come up for someone else and they'll remember this solution.
See ya, koreywill

 

[Twowaxhack]

Well, it was a simple solution. Took the galvanized fitting out (supply to the house) and the pipe was a little rusty but that's about it. No blockage. So, took the input side off, looked down into the hole and couldn't see much at all. Realized I was looking at the plastic dip tube. Pulled that out and the water stayed in the top of the tube and it was heavy. Took it outside, tapped it gently on the bumper of one of the vehicles, and lime/calcium particles started coming out. There were three or so solid pieces that came out. Finally got it emptied out and put it all back together. All is good.
Great ideas and great suggestions and I thank you all for the input. Maybe that problem will come up for someone else and they'll remember this solution.
See ya, koreywill

Good work