I have a tankless water heater with two valves on each side of it, to isolate it. One vale is on the incoming cold water and one is on the outgoing hot water. I have to replace the unit so I turned both valves off and took it off. No problems.
Now, the valve on the OUTGOING hot side obviously doesnt close because it started leaking back onto my floor. I even drained the lines on the hot water side of my faucet. After the water drains and the faucets drip, if you shut it off, water will eventually start coming out of the outgoing hot side. How is that even possible? The line is completely isolated I thought from the cold. It has no pressure on it, especially since there is a giant hole where my tankless was.
This tankless services one shower, one sink, one kitchen sink and the dishwasher...thats it.
How is it getting backpressure to come out where there is supposedly a break from the main hot water line?
Is it somehow crossing over from the cold side via a slightly leakey mixing valve from the sink, shower, or kitchen? They are all single handle models.
Now, the valve on the OUTGOING hot side obviously doesnt close because it started leaking back onto my floor. I even drained the lines on the hot water side of my faucet. After the water drains and the faucets drip, if you shut it off, water will eventually start coming out of the outgoing hot side. How is that even possible? The line is completely isolated I thought from the cold. It has no pressure on it, especially since there is a giant hole where my tankless was.
This tankless services one shower, one sink, one kitchen sink and the dishwasher...thats it.
How is it getting backpressure to come out where there is supposedly a break from the main hot water line?
Is it somehow crossing over from the cold side via a slightly leakey mixing valve from the sink, shower, or kitchen? They are all single handle models.
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