Hello I have a webasto diesel air heater in my 508D (firearm) When I turn up the controller at the front it runs on but does not say that it only blows cold air through the area. I had glow candle outside and it glows like n landing place at night. Then I took off the diesel line and pulled it with a syringe once if the pipe/filters are stuffed, but it came on diesel and it ran then also cheerfully. I also have no dosing pump in the diesel unit ng found that can be? vlt knows here still someone how you can see if it’s sprit or something else. had already thought about startpilot but then somehow didn’t trust me