2004 Viking Saga 2107 Popup Heater Question

There is a small sliding switch on the bottom of the thermostat .
Turn to off. Look closely at the lever it has an arrow on it.
It may be very hard to move and "snap" into place.
Good Luck, Mike

No propane, no main flame.........NO HEAT. (unless an AC electric add on heat strip has been added to furnace discharge duct)

Furnace runs on DC power.....converter is supplying DC from AC power. Battery is dead or disconnected

T-stat is set to 'heat' or is shorted causing furnace to run.

Can't explain heat but furnace will run 5 minutes after you turn the switch off that should be on the bottom of your stat

Thank you for the comments

Here is a pic of my theormostat. i had to go up to a parts place and they said it doesnt have an off switch

Go to different parts place. Yours doesn't know Jack. Top left corner of t-stat says off. Gently slide t-stat bar to left till it stops, you will feel resistance and now firmly continue another 1/8 inch. You will feel it. Furnace should shut off 2 minutes later. You said lp tank valve shut off, you cannot have heat from lp furnace unless fuel is supplied to device. You may mistake a fully open service valve on for being closed. Try opening it, if it doesn't open you already have it open. Firmly turn clockwise to close. If it is closed you may have a leaking service valve not fully closing.