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Water still comes out of indirect water heater even with incoming water valve off
We have a Buderus S120 indirect water heater. Noticed the water is brown so I flushed the tank. One thing I noticed was when I shut the main incoming water valve off to the tank, I still got water pressure (lower) and water was still coming out of flush valve. The only way to stop water from coming in was to turn water off at boiler.
Does this mean the coil in the water heater is leaking?