RV Repair: Mobil Temp Inc. water heater, rv water heaters, propane dealer

Question
I was given a slide in winnebago camper that needs some work, the water heater was capped off  so I took it out to test it. the tank is holding water without  leaking. I wanted to hook  propane to it to see if it would work  but am not sure as to it requirements.  I was told by one person that said he knew a lot about rv water heaters and said I needed to use a 10 pound PSI regulator like on an out door cooker. The local propane dealer told me that I needed a 6 ounce reg. of which they both sold me. I would think the valve on the water heater should do what they are saying do I really need another regulator valve before the water heater gas valve? I hooked the 6 OZ. reg. up and the unit would not light. I removed the line from the valve to the jet and held my finger lightly over the opening while spraying with soapy water. There was only enough gas coming through to make one small bubble about the size of 1/4  of a pencil eraser. Should I hook up the 10 pound and try or not. The diapham seems to be good. This water heater has an ITT general controls gas valve mounted in a Mobil Temp Inc. unit made in Brighton, Mich. Model G 602, serial # 92329, 10,000 BTU, cap. is 5.7 gal, recovery is 8.4 gal per hr, working pressure 127 1/2 lbs., test pressure 300lbs.I think it says PT # 335328, . Should I be using any of the regulators on this I don't want to blow the valve but I want to make sure I have enough pressure for ti to operate. Thanks , Pete

Answer
Hi Pete:
A standard RV regulator supplies 5-7 PSI of pressure. The 6 oz. is not near enough and the 10 PSI is a little high but should work allright. I always install two stage regulators but I have seen many with single stage units. Good luck.
Bill