Has it worked previously or is this a new installation? If it's NEW then check that the valve is installed facing the correct direction. If it's backwards it won't pick up any antifreeze. If it worked previously check the hose for air leaks. See how well it picks up water from the tank and sends it to the faucet. If it works this way then reverse the valve and try again. It would seem that by isolating the valve that this may be your problem.
2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR -
2004 F-150 HD (Traded after 80,000 towing miles)
2007 Rockwood 8314SS 34' travel trailer
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