Max Run for Water Tank Pump

[jayness2020]

I'm redoing the plumbing in our 1972 27' Overlander. The propane hot water heater is near the rear, driver's side. The freshwater tank and 12 volt water pump is near the front, passenger side.


I have a city water inlet near the hot water heater. I was planning to bring water from the pump and tie it in to the city water inlet pipe, between the wall and the cold water inlet on the water heater. (With a check valve between the T fitting and the city water inlet fitting. There will also be a check valve in the pipe coming from the pump, so city water won't flow back down to the pump.)


Then there would be one pipe going from the cold water inlet T fitting to the kitchen sink. (Right now, we only will have water at the kitchen sink--no bathroom.) And one hot water pipe from the heater to the kitchen sink.


My question is -- does a 12 volt RV water pump have enough "umph" to pump the water all the way back to the hot water heater and then back to the kitchen?


Thanks in advance for any advice, help, and suggestions.


Jay

[CBWELL]

A good quality and capacity pump will have no problems with that. The larger the water line, the less loss to friction in the line. Use 1/2" pex for best results.

[jayness2020]

Originally Posted by CBWELL

A good quality and capacity pump will have no problems with that. The larger the water line, the less loss to friction in the line. Use 1/2" pex for best results.

We are using 1/2" PEX. Just bought a new Shurflo pump - 3.5 Gallons Per Minute, 45 Psi.


Well that's good to hear. I figured it should work, because people want hot water at the kitchen sink when bookdocking. But wanted to confirm before running and cutting PEX.


Thanks!

[BayouBiker]

The water pumps are positive displacement so the flow rate is mostly independent of the pressure so long as you don't exceed the pressure of the built in relief valve and the shut off pressure. 1/2 inch tubing will have a pressure loss of about 10-12 psi from the pump to the faucet at 3.5 gal/min from what you describe. That is getting near the top of ideal but it will work. The water won't jet out of the faucet like at home but it will be adequate and the pump will run continuously which is what you ultimately want. Good luck!

[guskmg]

If you want more flow you can always change the pump for 5.3 gym Remco Aquajet. Sure it costs more, but it is a night and day difference over the standard RV pumps.
guskmg