So we are having an issue with our shower where you turn the water on and at first it starts off hot but then it goes cold/lukewarm. The only way to get the hot water back is to completely turn off the water and then turn it back on again. Even when you turn it back on, its the same thing. Starts off hot and then goes cold again. We replaced the catridge and it still doesn't work. We still get hot water everywhere else in the house except for our shower. Not sure what else I can do at this point. Nothing has changed since this problem has started so not sure why all of a sudden we are having this issue. The only other thing that I can think of is that before this problem began, we had a problem where the water would come out of the tub faucet brown. Then that eventually stopped but now this is happening. Please help!!

We would need to know more about your system, because it could be a bad check valve, and/or pump, in a recirculation system.

Well we have forced hot water, is how our water gets heated (through the oil furnace). It has 1 knob to turn the water on.

Do you know the brand of faucet? If possible, please post a picture for identification.

It's a Mowen.

[www.homedepot.com]

I'm pretty sure it's this exact one.

Moen Banbury 1-Handle Tub and Shower Faucet



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Contact Moen and get a new cartridge and have your plumber install it correctly. Unless MA lets you do faucet repairs legally as a homeowner.

Catridge has been replaced twice by a plumber. That's not the problem.

after replacing the first one, he should have gotten "serious" and looked for the REAL problem.

Very true. So now we are trying to fix it on our own if it's a simple fix because as you know plumbers are very expensive.

The problem is that we would have to be there while it is happening to diagnose it.

Yea that is what I figured. I think it's one of those things that it could be anything and it needs to be looked at in person but I figured I would try it out here and get an idea of what it could be so that I could look at it.

when you turn on the shower and the water goes from hot to cold, leave it running cold and turn on a hot water faucet. what happens at the faucet.
i suspect the hot water producing coil inside the boiler has lost efficiency and can not keep up.
someone can check very easily by turning on the hot and feeling the outlet pipe at the boiler mixing valve.

The hot water in the faucet doesnt seem to be affected. We left the shower running cold and turned on the hot water in the bathroom faucet but there was still hot water coming out. It just wasn't as hot as usual so you may be correct actually.

I hate when that happens. You pay a licensed plumber to do a simple repair and they leave without testing their work.

Something sounds fishy. A licensed plumber was hired to replace the Moen Cartridge "TWICE" and left the job without testing the shower valve? Was it a handy man plumber or licensed plumber?

Best Wishes

In MA it better be a licensed plumber..

You were correct! It is the boiler mixing valve! Just had my furnace guy at the house and he told my husband that its completely rusted and corroded! Easy fix thank god!! Thank you so much for your help! Hopefully this fixes the problem!



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Also, beginning of March we had some annual maintenance done to the furnace and the technician had turnt down the temperature but never turnt it back on. haha but at least now after these two fixes it works! Thanks everyone!



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