I'm hoping someone here could help me. I have a Raypak RP2100 heater, model number CR185. I think the gas valve appears to be a Robertshaw millivolt natural gas valve.I'm trying to light the pilot on the heater after opening the pool for the season, but I'm unable to move the gas control knob from "Off" to "Pilot". I can push it down (a tiny bit), but it just won't turn. Has anyone had this problem before? My googlefoo isn't working well, because I can't find anyone else that has the same problem.