pressure balancing taps

[gregol1962]

I recently had a professional plumbing service install a one piece pressure balancing tap system to replace an outdated two tap system. They assured me it would prevent getting scalded or frozen in the shower. It does not work at all. You can get the water temp set, pull up the button on the tap and the shower is fine. A few minutes into the shower the water goes scalding hot. So, you press down the button and out of the tap is coming the correct mix of water temp. Pull the lever up and again you get scalded. The company that installed the taps tells me that happens occasionally and that I am expecting too much or that someone fushed a toilet, ran a tap, etc. Correct me if I am wrong, but isn;t that the whole idea of a pressure balancing system??? I got no where with them and they refuse to come out to address the problem, telling me there isn't one. I am an intelligent, well-educated person and I do not appreciate them patronizing me. Any suggestions before I call yet another plumber to come out and try to fix it, and pay even more money? Any suggestions would be appreciated.

 

[phishfood]

My understanding of a pressure balancing tub/shower valve is that it is intended to PREVENT scalding problems that could occur when cold water is used elsewhere in the house. That is why Florida code started mandating them in new installs in 1994, the year I started my plumbing career.

 

[johnjh2o]

The way pressure balancing works is when the pressure drops on the cold side the balancing spool will drop the hot equality. You may see a pressure difference but the temperature should stay the same. You ether don't have pressure balancing (which code says you must have) or the spool is sticking. What make faucet is it?

John

 

[gregol1962]

It is a Moen faucet. Not sure of the model number. I'd insert a pic of it if I could figure out how to do that. LOL

 

[johnjh2o]

The balancing spool is sticking. Moen faucets are known for that. You can try removing the cartridge and free up the spool or call Moen's 800# and they will send you a new cartridge free of charge. Seeing that you paid to have it installed I would be making your plumber repair it. Explain to him that it would be far better off for him the repair it then take the chance of a law suite because one of your children suffered from scalds.

John

 

[gregol1962]

Thanks John. I tried freeing up the spool and it will not move back and forth freely so I gave Moen a call. New cartridge is on the way! Very much appreciate your help!

 

[Mr_David]

Moen makes two types Posi-temp with the balance spool built in the on/off cartridges. Posi-Temp turns on counterclockwise from cold to hot.
The Moentrol has a pull on/ push off cartridge and turns left to hot Right to cold. Moentrol has a seperate balance spool.

When You shake the posi-temp cartridge it should rattle. That's the spool moving freely.

Keep in mind the balance type valve does not control the temperature. It only compensates for pressure fluctuation like some one flushing a toilet on the same system. If the problem is still noticable check the water pressure.
Could be other underlying problems.