That means there is air in the lines and must be bled out.
You have air in the system that has to be bled out
Yes, you can bleed the air out of baseboard heaters by opening the bleed valves located at the end of each baseboard unit. Make sure to have a container and a towel ready to catch any water that may come out. Turn off the heater and boiler before starting the bleeding process.
My bet would be the hot water heater cycling water through
Yes, it is normal to hear water running through pipes in a house, especially when faucets are turned on or toilets are flushed. This sound is typically a result of the water flowing through the plumbing system.
I think if the automatic fill draws water from your home water service it would not be unusual to hear a "running water" noise when water was being added to the pool.
Sting. Set them Free (if you love somebody)
I would check the toilets, that is about the only place water could be getting into the drain without seeing it.
Generally the running water sound under the dash is air trapped in the coolant system. This air then circulates through the heater core. Just check the coolant level in the radiator and make sure the overflow reservoir is full. Run a few heating and cooling cycles of the engine and recheck. This should help take care of the sound.
Your Heater Core is most likely leaking. Your heater core is under the dash inside the car which is why you can hear it, and also why you need to continually fill up the water.
You can hear it running. Unplug the fridge, then wait approx 1 minute and plug it back in; you should hear it kick on.
When a hot water tank is making hot water, you should typically hear a low rumbling or hissing noise as the water heats up and circulates within the tank. This noise is caused by the heating elements or burner working to heat the water to the desired temperature. If you hear loud banging or popping noises, it could indicate sediment buildup in the tank, which may need to be flushed out to prevent damage to the tank and ensure efficient heating.
they can hear better out of the water