I have a Jayco 4 sessions. Cold temps likely causing this. Just not sure what to do about it. The lever that pulls the main value open was stuck. Heated it with a space heater and got it to pull out. However, nothing coming out of the tanks (grey or black). Had the lever pulled out in wet bay, as well as the main valve. Suspect 15-20 degree temps may be a factor. Now using my propane furnace more than the electric fireplace. Thought that might help heat up the underbelly. Any suggestions?