[DougSleeter]

Need troubleshooting help for why my hot water supply is still dripping, even after disconnecting from hot water heater and letting it drain all night.

Replacing hot water heater.

Disconnected hot side from hot water heater after opening hot side on sinks/bathtubs.

Let it drain out of the tubs all night, but it's still running slowly.

WTF? Where could this be coming from?

 

[TarheelTerp]

Need troubleshooting help...

Can't figure what it is you're looking to accomplish but...
if the COLD water valve isn't off the water will keep flowing.

 

[DougSleeter]

Oh, forgot to mention that cold water is also off. It's a mystery that the hot water line inside the house keeps flowing (slowly) even though it's completely disconnected from the water heater.

Where could that water be coming from? I'm thinking there must be some other supply (cold) that is feeding the hot water pipes in the house. But HOW COULD THAT BE? It's a very slow flow, but won't drain out even after leaving it open all night.

 

[DougSleeter]

To clarify, the cold water supply TO THE WATER HEATER is switched off. But cold water supply to the house is NOT off.

 

[dj3]

1. Is the main shut off to the house on or off?
2. If it's off and you still have a drip, Check your water meter - is water flowing at off position? There should be a spinning flow indicator.
Possibly, you have a shut off valve that doesn't stop the flow 100% or a leaky water meter.

 

[MTN REMODEL LLC]

Different fixtures mix hot / cold before it comes out of the unit. You probably have a bad washer or mixing valve somewhere that lets the cold migrate to the hot line.

 

[DougSleeter]

Thanks MTN Remodel - I think that must be it. A bad washer or mixing valve. It's about the only thing that makes sense.

I'll just keep the bath tub hot open while I replace the water heater. I don't want to shut the cold water off to the entire house, so it's fine to just let it drip for a while while I'm installing the new water heater.

I was just confused as to where that water could be coming from. Mixing valves are probably the culprit.