Propane pressure issues...

[LuvinmyRV]

Good afternoon all,
Hope all had a great holiday season. It's been awhile but I do enjoy this site and the helpful information I receive when I come here. I own a 2001 Georgie Boy Landau and I'm having issues with my propane tank pressure lately (mostly since its colder). It seems when my tank level falls below 1/2 full my furnaces, hot water heater and stove won't operate properly. The furnaces will start blowing cold air, the pilot light won't stay lit on the hot water heater and the eyes on the stove barely stay lit BUT, when I have the tank filled (30 gal tank) it only takes 7 - 8 gallons to fill it and everything starts working fine again!! Also, the colder the weather the worse the symptoms become. The obvious thing would be the tank regulator I suppose.. Any ideas about what might be causing this? I'm pretty handy with most repairs but this one is an odd one.

Thank you in advance for ALL reponses!! Take care, Jim

 

[Kirk]

Re: Propane pressure issues...

While propane will change from liquid to gas as low as -44 degrees, the pressure in the tank does fall. At ambient temperature of 90 degrees that tank will contain 150 psi gas but at -10 degrees it falls to 17.5 psi. You do not say where you are or what the temperature is, but if cold enough it will have a direct impact. The pressures given come from http://www.flameengineering.com/Propane_Info.html

There is another possible cause. Propane always contains some oil residue. If some of that collects inside of your pressure regulator, that can have a very significant effect on the supply, and that impact is greater as the tank level falls. The volume of liquid is assumed to be insignificant in the temp/press chart that I linked to, but in practice a full tank does have somewhat greater pressure inside than one that is half full. And the effect of temperature drops has more effect as well.