Hello,

I just moved in to a "new to me" older house built in the 70's, problem is with the bathroom sink water supply... the faucet it a delta single knob, and when I turn on the hot water I get cold ( the cold works fine ), I turned off both valves under the sink and tried them 1 at a time both are sending plenty of water its just always cold, the hot water in the rest of the house works great, any ideas, thanks in advance

I turned off both valves under the sink and tried them 1 at a time both are sending plenty of water its just always cold,
Are you saying the left hand angle stop,( the hot side) only produces cold water? Back to you, Tom

You should call a plumber, either your water heater doesn't work or the plumbing for that particular faucet is wired wrong. The same thing happened to me but to my washing machine.

I doubt if we have a supply line "wired wrong" if the home is nearly 40 years old. Was any plumbing work done recently and how is the hot supply to all other fixtures?

Yes speedball1, both the hot and cold supply lines produce cold water at the faucet... claire58 & ballengerb1, all the hot water for everything else in the house works fantastic including the bathtub that is 5 ft from the sink, as far as any new plumbing work being done I have no idea but nothing looks "new"

Just help me clear this in my mind. If you shut off the cold stop valve under the sink and open the hot valve above the sink you still get cold water, right?

Yes, that's rite I got cold water coming from the hot supply line at the bathroom sink only, hot water works fine everywere else in the house... its the wierdest thing I ever saw I'm totally baffled

Under the sink, which stop did you close, left or right?

I closed them both then tested each one individually... cold water on both...

I am at a loss on this and hope Speedball1, Tom, will come back with his thoughts. All that I can think of is that the previous owner did some work on the plumbing and has somehow made a huge mistake. In the meantime try to trace the hot and cold supply lines back through the house if you have access. We know hot water leaves you heater and somewhere along the run is no longer connected to the line supplying the mixer. Your thoughts Tom?

Did this just come on all of a sudden or has the hot water gradually become cooler and cooler until it was dead cold? One more check. Run the hot water in the tub/shower until it runs hot. That gets the cool water out of the main and hot water into the bathroom branch. Now shut the cold water angle stop off under the lavatory and turn on the hot water in the faucet and let it run for at least two minutes. ( I realize you did this with Bob but humor me.) The water's still running cold? Not even a little warm? As a rule when we get a problem such as yours we find the problem to be in the faucet itself. But you are telling us the hot water angle stop and hot water supply are running cold. This takes it out of the faucet and put the problem in the system. Even if the hot and cold were somehow crossed the hot side should rrun a little warmer then the cold. Has there been any work or additions on your water system of late? A neighbor or handiman helping out? Give ne something to hang my hat on here! Some minor detail you've neglected to mention? Anything come to mind? Let me know, Tom