I have a few box fans that after excessive air temperature they shut down and don't restart. Any idea what the problem could be?

When you say the the furnace re-starts 8 times before shut down, what is cycling 8 times? just the indoor blower or is the main burner re-firing 8 times? If it's only the fan it sounds like the fan control.

Change the automatic temperature detection settings. Many of these Dometic systems have an automatic indoor outdoor temperature gauge that determines when it shuts off. This is separate from the normal thermostat. When the outdoor temperature reaches close to the indoor set temperature the unit shuts off.

The thermostat has a differential built into the temperature sensing operation. The differential is normally a degree or more. If the stat shuts down at 72 degrees it should not start the unit again until the temperature in the room reaches 73. If the AC runs and cools properly until it shuts down, I would check the thermostat. The AC can not restart immediately after it shuts off because the pressures in the system are too high at the compressor. It takes a few minutes for the pressures equalize allowing the compressor to start. If the stat tells the unit to start under high pressure, the compressor will shut down on overload. It will start and run after the pressure falls enough for the compressor motor to run.

Inside cooling coil frosted up? turn to run inside fan only until melted away & restart. Possible reasons for this a)dirty condenser down at the compressor which could be brushed but DON'T bend the fins. b0 refrigerant leaked out thru a existing crack. c)poor compressor pumping ability. d) excessive load of warm air entering the cabinet so the system can not reach the request temperature & shut off the compressor to allow that frost to defrost off the evaporator(inside fins) or the system does get too cold & then frosted to the point & never shuts the compressor off so it can defrost.

Depending on the age of the furnace you may be able to adjust the cool down. On some furnaces there is a silver box usually made by honeywell. This is your fan limit control. If you take the cover off you will see a dial with different temperature settings with 3 pins in a grove. The first one is fan on with temperature rise this turns the blower on when the furnace starts and warms up. The second is the fan off after furnace shuts down, this would be the one you want to adjust to a higher temperature to keep the blower from blowing cold air. The last pin is the high limit if the furnace gets to this temperature it will shut the furnace off but keep the blower running. Make sure that the thermostat fan option is set to auto and not on.

You need to clean it out with some compressed air.

Make sure the laptop is turned off of course.

If you still have heating issues, then you'll need to take it apart and put a new layer of thermal paste on the heat sink / cpu.

Best of luck!

Sounds like the relay to me.

check your cables. it may be in the way of the fan's fins. also clean your fan for dust.

Reddy suggests: 1. Propane supply may be inadequate 2. High surrounding air temperature causing thermal limit device to shut down heater 3. Restricted air flow 4. Damaged fan 5. Excessive dust or debris in surrounding area solutions are: 1. A) Refill tank B) Provide additional and/or larger tanks. 2. This can happen when running heater in temperatures above 85° F (29° C). Run heater in cooler temperatures 3. Check heater inlet and outlet. Remove any obstructions 4. Replace fan. 5. Clean heater. could not get manual for your exact model but if you want manual for RLP 125 then; http://12.153.20.74/manuals/113893-01C.PDF appears to be the same beast. Hope helps :)