Shaving tonight at the two-handled Glacier Bay bathroom sink; went to shut it off and the water wouldn't stop flowing. Bottom line: the hot water valve is now reversed. Water is off when hot handle is in the normally open position (6 o'clock), water flowing when handle in the normally closed position (9 o'clock). This happened very suddenly. When I was messing around with the hot and cold valves trying to figure things out, there was a brief discharge of black water. Any insights appreciated!

Most likely the handle has broken and rotated on the stem.

Thanks, NC Plumber. So is this just a matter of replacing the hot water stem/cartridge? Or do I need to drop in a whole new faucet?

take the handle off and look at the inside where it fits over the end of the faucet stem.
if the grooves are worn enough to allow it to slip around, all you need is a new handle. the handle must be exact as all manufacturers intentionally make handle grooves different.
if the grooves on your handle look fine, then there is a problem with the stem grooves or the stem innards themselves..
at that point you can either replace the stem or the whole faucet.

What did you do when you were "messing around" with them. It sounds like you just put something back together backwards, especially since the handle does operate normally just backwards.

All very helpful replies, thanks.

No, haven't taken anything apart yet. "Messing around" just meant turning hot and cold supply valves on and off trying to isolate the problem. At one point a short discharge of blackish water came out of the spigot, then the flow quickly cleared. Unfortunately, I did not note how the supply valves were situated when that occurred.

You now have a valid reason to throw the Glacier Bay in the trash where it belongs

What you describe usually only happens when they are taken apart and then reassembled improperly.

It's fixed. I ended up replacing the cartridge. I suspect my kids had been slamming the handle shut too much and something inside the cartridge twisted or failed somehow. Of course the hot water shutoff hadn't been worked probably since 1972, so that failed and had to be replaced (thnx PB Blaster). But it's all done now. Thanks again everyone.



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