no water coming out of faucets

It sounds like you have a small leak somewhere in the pump and so its not building enough pressure to shut off/ or air in a line. These pumps are like the pumps on our agricultural sprayers, when they reach a certain pressure they cut off until you open faucet. So if you have some air trapped in a line it will keep pumping until it compresses that air and reaches the shut off pressure. It will reach the shutoff pressure much quicker with no air in lines because you cant compress a liquid. So if air is trapped in the line its not reaching the max pressure. Sounds like you have air trapped in a line somewhere. Can air be trapped in the hot water heater. Because it sounds like quiet a lot.