This past weekend I installed a 3 way valve in the water line from my FW tank in order to provide an inlet for antifreeze. The plastic 3-way valve that I picked up at the RV dealer has 3 "flair-it" fittings (see pictures) but the nuts that the go over the water lines won't fit on the braided poly water line from the FW tank, so I used 1/2" stainless hose clamps instead. As you can see from the picture, the fittings don't have barbs but it seems to be long enough that the hose clamps grab securely.
The TT is in storage so I wasn't able to put water in the FW to test the connection to make sure it's watertight.
Will this work or do I need to modify it? I do have some 1/2" clear plastic hose that the nuts will fit on so I could used a couple of splice connectors to go from the braided line to the clear line and back in order to connect the valve in line.
Update on this problem. I had a chance to test the installation this week and it didn't work. The fittings are leaking. The pump was sucking air and the fittings were leaking a bit of water, so I had to remove the valve and get a barbed x Female hose thread fitting to reconnect the water line.
Unfortunately the braided poly water line that the factory installed has an ID that's slightly smaller than 1/2" or at least not very flexible and the OD is slightly larger.