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No hot water but not a cartridge issue.

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Carlg

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Hi there. I'm hoping to get some ideas on a hot water issue in a friend's bath tub. I'll explain what the behaviour is and what we've done to diagnose it. Hopefully there will be some more ideas!

Problem: No hot water flowing from a older Moen single handle faucet in shower head and bath spout configuration. This is an extremely seldom used bath. Perhaps > 1 year.

- Cold water works fine, but as the knob is turned to introduce hot water, the flow stops.

- There is adequate hot water and flow pressure to the rest of the house.

There are individual shutoffs behind the cover plate of the faucet handle. There is a brass (?) type fixture with 4 copper pipes leading into it. Hot water coming in on the left, cold water on the right, supply pipe to the shower head above and supply pipe to the spout below. I'm not sure what this piece is called.

It seems that 99% of the time the cartridge is the culprit so a new cartridge was purchased and replaced without difficulty. The problem remains.

We tested water flow without the cartridge installed at all at and there was no hot water flowing through where the cartridge would normally be.

The water shut off (nut with little spring and copper with rubber ring) was then replaced. The problem still remains.

So we then removed the local water shut off completely (while the main was shut off) and then turned water main back on. There was strong flow out of the hole where the shut off valve would normally be. The was also hot water coming out of the bathroom tap.

So, we know there is water up to the 4 way brass appliance, the cold water works fine on and there is hot water to the rest of the house.

We were thinking possible blockage of some sort? We poked around with a tiny metal rod, to see if anything would work but still no luck.

Right now, we are spraying CLR into the cartridge hole as I'm not sure what else it could be.

If anyone could chime in with suggestions, ideas to try that we haven't tried already we would appreciate it very much! I'm scratching my head!!

Thanks in advance!
 

breplum

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First guess it that it is a old moentrol pressure balancing valve.
There is a balancing spool in those and it needs servicing, by taking apart and evaluating.
 

Carlg

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Hello breplum. Thank you for the quick response and advice. Will remove the balancing spool first thing tomorrow and evaluate....it's one thing we haven't looked at, and there is one there!

Thanks again.
 
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