H2O pump dual duty?

Pump discharge and city water both supply the same cold water main plumbing line which then feeds water heater, faucets, shower, toilet etc.

Turning pump on while connected to city water will help maintain steady constant flow. If city water pressure is lower than pump discharge pressure, check valve in city water connection will close until pump discharge pressure decreases enough to allow city water check valve to open.
If city water pressure is higher than pump discharge pump will not run.

Pump only takes suction from fresh water tank.

We do it all the time for showers to get the increased water pressure and flow. FW Tank fills from city water connection, so it is no problem to just turn valve to refill fresh water tank if necessary.

We do that alot when camping at camp grounds with city water. Our pump only draws from the fresh water tank which means it has to be filled manually in our case.

I don't think I have ever tried mine with city water hooked up. Either one or the other in my case...

The newer setups allow the fresh water tank to be filled from the city water connections I think...

Roy Ken

dbbls wrote:
It is pumping from the fresh water tank.

Thank You! (I sorta thought that but was unsure!)

It is pumping from the fresh water tank.