Garage heater problems!!

Ok some of you may know I have finally installed my Big Maxx furnace/heater in the garage. Its propane fed. I got everything hooked up propane and elec. wise. Now when i turn it on, the LED if slow flashing, which in the manual means no call for heat. Let me tell ya Im screaming for heat. I didnt buy or install a thermostat as it is optional and I dont plan on running the furnace when I am not in the garage. Any one got any ideas as to why there is no call for heat??