I live in a condo and while updating my bathroom I was turning off the hot water valve under the sink and it came off in my hand! I turned off the water main cut off valve located near the hot water tank. The cold water was off and I let the hot water run for almost 1/2 hour thinking I was draining the hot water tank. The hot water NEVER stopped or even slowed down... is the cut off valve broken? Do I have to turn off the valve coming into the building to fix it? Should I have a separate shut off valve for the hot water? Thanks!

You have a few possibilities. You may have a failed valve, you may have water crossing over from a single handle faucet. I have seen a moen that was closed cross over.

If it was just the handle that came off the hot water angle stop simply replace the handle. Please explain what happened more fully. Why would you want to drain the hot water tank? If the cold water shut off on the heater's faulty then you still have a house shut off valve that shuts off the entire unit. Regards, Tom

i live in a condo and while updating my bathroom i was turning off the hot water valve under the sink and it came off in my hand! i turned off the water main cut off valve located near the hot water tank. the cold water was off and i let the hot water run for almost 1/2 hour thinking i was draining the hot water tank. the hot water NEVER stopped or even slowed down...is the cut off valve broken? do i have to turn off the valve coming into the building to fix it? should i have a separate shut off valve for the hot water? thanks!
I wanted to empty the hot water from the lines so I could repair the hot water valve under the sink... I thought the water would just gush out if it wasn't completely turned off

I'm still attempting to find out what the problem is with the hot water angle stop under your lavatory. Handle came off? Leak? Let's address one thing at a time. First the angle stop and then your shut off valves. PS: You don't need to drain the hot water tank to work on the angle stop.. Regards, Tom,

[quote=laurajoan]today plumber installed a ball valve to hot water heater and also replaced handle that fell off so problem solved... thanks everyone!