Originally Posted by Sooners67
... I left external water running to RV to allow filling up of fresh water tank. It was 45 minutes. The indicator light said it was not full. I don't know what to do.
How do I know water is going to fresh water tank?
How do I know it's full?
How much does it hold? ...
45 minutes sounds like a long time. The FW tank is often either 39 or 60 gallons. Assuming a slow flow from the hose of 3 gpm it shouldn't take more than 20 minutes to fill a 60 gal FW tank. With normal pressure and flow it should be at least half of that. Have to assume water is not running out the bottom of the trailer while you're filling up, right? The filler is very similar to the gas tank on your car. When it's more than full it starts running out where you're putting it in. Just before that point it stars spitting and sputtering out the vent next to the fill pipe.
Your description sounds like the pump is not getting a prime from the tank. Check the connections to the inlet of the pump for tightness. There should be a round strainer in line just before the pump inlet, unscrew the cap and make sure the screen is clean, then put it back together and check the plumbing going to the FW tank for other connectors that may be loose and allowing the pump to suck air.
In particularly stubborn cases, I've heard a person could open a faucet, switch on the pump and holding an air hose in a cupped hand over the fill pipe use the compressed air to apply a slight pressure to the tank to get the pump primed. These pumps normally don't have a problem getting a prime if there's water in the tank and the connections are snug.