Some times the pump gets air locked. I had that happen and it will not draw from the jug.
Open a faucet before turning the pump on, It gives the pressurized air a place to go and the pump can draw easier. Make sure the hose is not sucked up against the bottle sealing the hose off. Some have the end of the suction hose cut on and angle to help prevent the sucking of the jug.
Jiggle the hose with the faucet open and pump running if it does not catch prime. Once it does catch it will suck that gallon dry quick so be ready to turn the one faucet off and work your way thru the camper. 2 people make it easier when it does not want to cooperate.
Good luck and hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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