turn the propane tank on. switch the thermostat to the on position. slide the temp level to where you want it. after 20 seconds or so you should hear a fan turn on then some clicking sounds. that is the igniter trying to light the propane. if the planets are aligned your furnace will start heating the rig.
Before doing the above, you need to light the pilot light. There should be a little threaded cover that once open will reveal the pilot to you. Make sure the gas is turned on and the thermostat is off. It must be off, or you will experience a blast of fire once that pilot lights. Hold a flame to the pilot and press in the black button on the face of the furnace. This gets the gas flowing to the unit and it may take several moments before the pilot stays lit. Once lit, the button can be released. Put the cover back on over the pilot light and then you can go to the thermostat and set your temperature. You will here the furnace fan kick in and things will almost immediately begin to get toasty warm inside. Also, please get yourself a carbon monoxide and propane gas detector, install it and keep it functioning. Where in Vancouver are you located?
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Cameron & the Labradors
Kai & Samm
North Vancouver, BC
Canada
You will need a power source for this furnace to function. If the battery isn't working, then you will need shore power. The fan draws a lot of juice from the battery, so it will need to be recharged regularly if the furnace is used. If there is no shore power, then a generator would be needed.
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Cameron & the Labradors
Kai & Samm
North Vancouver, BC
Canada
Has the furnace been used at all recently? Does any one even know if it works? Given the time of year, has the trailer been winterized? Have the pipes and holding tanks been cleared?
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Cameron & the Labradors
Kai & Samm
North Vancouver, BC
Canada
All seriousness aside. I had a 73. Parts are unavailable or extremely hard to find, as are techs who will work on them. Techs won't work on them for liability reasons. The can be dangerous. If there is a leak in the combustion chamber they can croak you.
I stubbornly would not give up on my 73 furnace. Most owners of early 70s I have heard from eventually decide to replace the furnace with a new model. as I finally did. Not a hard job.
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Pay no attention to the man behind the curtain- WoZ
As Lumatic pointed out, it may well not be a good idea to get it going. They rust inside as they age, so at a certain point they become unsafe.
Would you use a 36-year-old furnace in a house? Not likely, unless you had it serviced very carefully, right?
Also, even if it worked, you need power (which means an investment of some kind). It may be time to step back and consider just how far you want to take the winter use idea...
__________________ ♫ The road to a friend's house is never long. (Old Danish Saying)