Do you have 100% propane or is it some or all butane? If all or even partly butane it can "freeze" (quits turning to gas) at much higher temps than true propane.
2009 45' Magna 630 w/Cummins ISX 650 HP/1950 Lbs Ft, HWH Active Air
Charter Good Sam Lifetime Member, FMCA, SKP
RV'ing since 1957, NRA Benefactor Life, towing '21 Jeep JLU Rubicon Ecodiesel