A week or so back I started my 2006 HR Imperial motorhome up and heard a rushing noise coming from behind the instrument panel. Upon investigation I discovered a 1/4" air hose had come loose from the pressure gauge and was blowing air rapidly. The connector had given way and no longer worked. The connector is a "push to connect" type fitting with a #10-32 threaded end which screws into the pressure gauge. I called HR parts and they did not have a clue what I needed but gave me the instrument panel manufacturer (Actia). I contacted Actia, they also did not have a clue about the part I needed, but would sell me a new pressure gauge unit for $223. After doing some research on the internet I found a company that sold the exact fitting I needed for $11 for a package of 5 fittings including shipping. here is the web address:
MS14-10N | Male Straight Air Fitting: 1/4in tube to #10-32 male thread, 5/pk [/U]
This will take you right to the fitting. I hope this helps someone who encounters the same problem.