I have a 2015 Itasca 27N with constant leaks. After driving 2-300 miles the fittings come loose at the faucets. I tighten them up and all is good until I drive another 2-300 miles, Is tape or thread dope suppose to be on these plastic fittings?
I plumbed my trailer from the tank to all the faucets. I used PEX pipe, brass full flow valves before the supply lines, braided stainless supply lines to everything. I rebuilt the 44 year old faucets with new washers. I've found that plumbing is one spot where saving money is not efficient. If I have a leak and have to come back to it later, any money saved is blown away.
Replace the fitting that you just tightened. Probably just get a new faucet while you have the fittings loose. Nothing very special just get what you need at Lowe's etc.
Don't connect them direct I had problems with mine till I replaced the direct connections with the braided faucet hoses.
9-11 WE WILL NEVER FORGET! FULLTIME SINCE 2010 17 DRV MS 36rssb3 17 F350 King Ranch CC DRW 4x4 6.7 4:10 B&W hitch John โA good traveler has no fixed plans, and is not intent on arriving.โ Lao Tzu
Usually faucets in RV's are made by pheonix. First time they leak replace them with one from a hard ware store. I usually replace them with moen. Look the same but last forever.
I replaced all my faucets in my older Fleetwood and never had a problem, the Winnebago leaked from day one and the dealer claimed to have tightened them also.