water NOT siphoning to RV. NEW PUMP

**Nano18** · 05-26-2023, 06:07 PM

I have a nautilus P1 system. We have a brand new pump that is working & all lines are connected properly. The pump is not siphoning water / antifreeze from the outside connection. When I disconnect the pump inlet hose (#5) & pour water directly into the inlet tube the water takes and distributes to all the faucets correctly. However, when attached to the nautilus system, with the knobs all in the correct position, it is NOT taking the water. PLEASE HELP.

**dryfly** · 05-26-2023, 08:14 PM

There are times when my pump also doesn't want to siphon. I have found that holding the hose being used for siphoning up and filling it with water, then turning the pump on and quickly placing the end of the hose in the water bucket, seems to prime the pump. Also, have the water bucket or antifreeze jug as high or higher than the Nautilus intake helps.

There are several posts on this forum that suggest removing and reversing the small screen on the intake.

**Nano18** · 05-26-2023, 08:48 PM

Thanks!
We tried both of those as well. When I fill the hose and keep it as high as possible with the pump on it still just doesn’t go anywhere unfortunately.

**FT4NOW** · 05-26-2023, 09:10 PM

Did you try flipping the inlet screen as mentioned? When you flip the inlet screen, it holds the check valve open.

**Nano18** · 05-27-2023, 04:31 AM

Originally Posted by FT4NOW

Did you try flipping the inlet screen as mentioned? When you flip the inlet screen, it holds the check valve open.

Yes tried that too.

**FT4NOW** · 05-27-2023, 06:39 AM

Originally Posted by Nano18

Yes tried that too.

Does your RV have a built in water filter? The filter should be removed, but the canister case should be installed. It could help to fill the canister with water or antifreeze to minimize the air in it. Also make sure low point drains are shut while trying to get the initial suction from the pump.

**Tom Traveler** · 05-27-2023, 10:59 AM

Originally Posted by dryfly

There are times when my pump also doesn't want to siphon. I have found that holding the hose being used for siphoning up and filling it with water, then turning the pump on and quickly placing the end of the hose in the water bucket, seems to prime the pump. Also, have the water bucket or antifreeze jug as high or higher than the Nautilus intake helps.

There are several posts on this forum that suggest removing and reversing the small screen on the intake.

This has been my experience also. So far, filling the raised and inverted hose, turning on the pump, and sticking the hose into the bucket while pumping has worked. I think it helps if you keep a faucet open somewhere to reduce back pressure on the pump. So far, I have not had to reverse the intake screen. I also pull the filter cartridge and stick an empty, capped water bottle into the filter housing to reduce the amount of anti-freeze in the filter housing.

It seems like I’m always doing this in the worst conditions. The first time, we had just brought the new 5er home from southern Nevada in December. I was winterizing in the dark, below freezing, in a snowstorm, trying to beat the deadline for the storage yard’s 10 pm lockout, and figuring things out for the first time. The last time, I did the winterizing before we left the last RV park to come home, again in December.