I have a Grundfos recirculation pump on my hot water heater.
I've just now unplugged it.
I hear a "whooshing" noise, like the sound pipes typically make when water runs through them.
I don't have any faucets turned on, though.
My house was built in 1977 and is slab construction. To my knowledge, no pipes are run through the slab and they are all located in the attic.
Down my hallway, I have 3 hallway tiles that are extremely warm.
No moisture apparent from broken pipes or anything like that. No lack of hot water; I can take a long shower with no problems.
Even with the recirc pump unplugged, the warm tiles are still warm and the whoosh noise is still going on.
Why?
Even when plugged in, it was only set to go on a handful of times a day, for only 15 minutes.
I've even gone to the far end of the hot water line and turned off the hot water feed, which disables the hot/cold bridge that makes the recirc pump able to work.
So:
-Pump has no power
-Bridge is disabled.
I still have:
-Warm floor tiles
-whooshing sound of running water, but no faucets on and no wet walls anywhere and no water leaking out my foundation.
What the heck is up with my house?