At the rally this past weekend, I was able to help several fellow Campers having some trouble with their campers. I thought I would share some tips to help others getting their campers ready or Spring. The first thing I recommend is for everyone to turn on their propane tank and go inside and light their stove. For some reason, the propane in the lines goes bad by sitting there like old gas does in a lawn mower. After a minute or so, the gas should light up. Let it burn for a minute or so to get fresh gas in the lines. For those with ovens, Light the oven pilot light and turn the oven on shortly to see if it works as well. Sometimes the thermo couplings goes bad where the pilot light will not work. Now turn on the refrig. with gas to see if it ignites and the campers heater.
I recommend everone to hook up to a good water supply and flush the entire water lines by turning the hot and cold separately at each faucet including the outdoor showers. Make sure you by pass at the water heater is turned off and your water heater is full of water before igniting the gas on it. 
I was able to help a couple who had a brand new camper with a Coleman a/c unit on the roof. They had heat strips in their unit to keep the camper toasty on those cool mornings. They didn't know they had it installed on their unit because the dealer didn't tell them. So, make sure you hook your camper to a 30 amp electrical service, go inside and turn the temp knob to red, turn the fan on low or fast fan, not a/c low or high. in 10-15 minutes you should feel warm air.
While we are on Electrical, turn your refrig. on, after 15 minutes or so, you should feel the upper vents on the outside of the refrigs. outlets. You should feel warm air coming out. Your refrig. is working. We had one camper who's counter top was very hot to touch and refrigs not working properly. They stated it had been that way for 10 years. After looking, we found where someone had puller their refrig. out and a upper metal plate had dropped down and covered the exhaust opening. We removed the screws and pulled the refrig. out partially and pushed plate back up on Insulation, reinstalled refrig. and turned it on. It worked great after 10 years of none use.
As always, pull your tow vehicle up to the camper and hook your plug in to check camper lights for proper operation before your first camping experience of the spring! And of Course, check those Fire Extinguishers, CO/ Smoke Alarms! Happy camping!