Espar bunk heater not heating blowing cold air *repair tutorial*

The issue: Espar airtronic D2 bunk heater not blowing warm air, blowing cold air. cycling on and off doesn't reset code. Not working after turning off.

Additional information: There was extensive trouble shooting prior; including, checking the entire electrical system, replacing the bunk heater fuel pump several times, replace the glow plug, clean the combustion chamber, replace the inside screen of the combustion chamber, and replace the entire fuel line from the espar unit to the flow tip of the fuel pump. Nothing of the listed above seemed to be the root cause of the issue. unTIL, the fuel line was ,mentioned previously, was replaced for a larger diameter 1/4 outer diameter as shown on image number 1. The original fuel line was extra thin probably 1 millimeter in inner diameter with no fuel visibility.

Identification of the issue: The issue with this unit was found to be the fuel tank fitting, as shown on image 6, is probably leaking air into the fuel hose intake not allowing the espar fuel pump to pump pressurized fuel across the the fuel system to the espar. In other words, pump can not lift fuel from the tank into the espar bunk heater causing the unit to cycle on and off without ever priming the fuel system.

Thermoking evolution users: If the espar unit has an error code and after turning the on/off switch located on the apu and on the truck dash and pressing the power button on the bunk area many times after waiting 15 minutes and the espar bunk heater DOES NOT seem to RESET and the vent does not start blowing cold air through it ***then*** the APU positive cable off the truck batteries needs to be disconnected and reconnected after 15 minutes. Make sure the apu power switch, dash switch and bunk power buttons are OFF position before disconnecting positive cable from battery.

Different solution: it was decided to run the bunk heater from a side diesel tank located inside the truck. This includes setting the tubbing from the driver side panel into under the truck. The reason is to improve the passage of fuel using 50 percent gravity like if it was relevant and to install a different fuel hose system that allows the visualization of the the diesel fuel from the side tank to the diesel pump to the espar bunk heater. Much more efficient, in my opinion, but the draw back is that the tank needs to be refilled and kept away from heat sources and in a safe area to avoid spills.

Materials needed: 7 feet of quality FUEL hose of your choice. DO NOT use regular hose tubing. HOSE FOR FUEL ONLY.

Please see images 1 through 7 attached below.

***Try everything mentioned above, if you decide to do so, at YOUR VERY OWN RISK***
: ) lol...foolish.​

 

I installed that. The fuel pump is mounted and secured. Not shown on the images. What's on display is the issue noted on the post and its solution. Not an installation job for you to admire. In my opinion, it looks fine. Espar heater does work now and no fuel line visible for is secured under the cab.

 

........i am as confused as you are understanding the nature of your comment.

 

Right. Two separate questions. Well... sir, read the post and interpret as you wish. Good bye.

 

***UPDATE: Not recommended to have fuel reservoir inside at the same level of the bunk heater. Reservoir must be at the same level of truck fuel tank lower than bunk heater, so fuel doesn't flood the Espar combustion chamber.

 

thanks Luwi67. That is a possibility as well. the pickup tube inside the tank. I know it is not obstructed because I did blow air through the tube and it does bubbles the diesel under...for someone like myself that is not very familiar with espar troubleshooting the system can be frustrating that's the reason why I posted this due to the lack of information available. If thermoking wanted to facilitate the process they should sell the system, but installed separately with its own espar screen because the integration system thermoking apu and airtronic espar does not provide a reset button to clear the codes other than turning the on button off and wait half an hour every time.