Shower - hot water in only one certain position

[Jan Philips]

At my parent's house, one shower has a handle that goes from hot to cold. You have to put the handle at one certain position to get any hot water, and then it isn't very much. If you move the handle just a little bit in either direction, the water is cold. (The sink in the same bathroom gets plenty of hot water.)

My mother asked the plumber who installed it and he said that the reason is that it is a low-flow shower head. I think that the valve is either installed incorrectly or messed up.

What do you think it is likely to be?

[krw]

If it's "hot" in one position and cold on either side of that, yes, the valve is screwed up. With some of these valves, the stops are in the handle. The valve may be in the wrong position. Does it, by chance, operate backwards? You might try pulling the handle and rotate the valve 180degrees and reinstall the knob.

[Jan Philips]

I believe it is, the position that gets some hot water is about the 3 oclock position.

[Ed Pawlowski]

Is it a temperature controlled anti-scald valve? If so, it has to be adjusted to allow more hot to flow in the mix. Since it goes cold again after the hot spot, it may be an adjustment or it could be a defective cartridge.

First step it to get the model and see if there are instructions on line. If they does not help, call the customer service of the manufacturer. They usually offer good service and good warrant coverage.

I don't see how a low flow head would affect temperature. Get a new plumber next time.

[Jan Philips]

Not as far as I know.

[krw]

Try moving the knob (on the valve) 90 degrees. As I said, pull the knob, rotate the valve 90degrees CW, and put the knob back on. That might be the wrong direction but it's worth a couple of tries.

[Evan]

As far as you know: When was it installed ?

Take a picture of the valve in question, host it somewhere on the internet and post a link here...

You are either not knowing what to look for on the valve to describe it OR are being deliberately vague...

~~ Evan

[Jan Philips]

Is there any marking on the valve cartridge that shows which way it is supposed to go?

[krw]

Not that I could tell. Yes, I made this mistake, too. ;-)