Webasto Heater Pump Issue

[cthayn]

I bought an Webasto AirTop 2000 STC petro heater and have installed it according to the instructions, but have never been able to start it.

I am having problems with the initial start up of the heater. It appears that the fuel pump will not pump fuel. I have installed the pump in the proper orientation and location. The fuel lines are less than 1/2 meter on each side of the pump. The electrical connections are working and I can hear the fuel pump “ticking” as the heater goes through the start up cycles. At the end of each start up cycle I get the H02 error.

In my attempts to get the heater started I have primed the fuel feed line several times. I am confident that there is fuel at the pump intake, yet when I remove the pump outlet line, no fuel pumps through as the pump is cycling. I have even temporarily lower the pump below the fuel tank and confirmed there is gravity feed to the pump. Still no fuel comes from the pump outlet.

Support from Heatso has been very limited and I get no response from Webasto. I thought I would query the group here to see anyone has any ideas.

Below are a few pictures of the install.

Thanks.

[unreng]

According to the operating manual, the control panel should show faults that may help with diagnosis - https://dealers.webasto.com/service/...s_FileId=17842
Don't wanna sound obvious, but is the pump installed in the proper orientation? in vs. out?
Other than that, the manual isn't very descriptive for troubleshooting...
[from the manual above]
If the system is fitted with a combination timer, when an error occurs an error code is output on the timer's display until the heater has been rectified. The error code is output if the heater is fitted with a control element after an error has occurred by the switch-on indicator/error code indicator flashing. After a burst of fast flashes the error code will be output by a sequence of long flashes, the number of which is shown in the table below.
If serious malfunctions such as overheating or failure to start reoccur, the heater is locked (F 12) and can be put back into service by disconnecting the power supply with the heater switched on (e.g. by removing fuse).
Error code Meaning
F 00 Control unit error
F 01 No start (after 2 starting attempts)
F 02 Flame failure (at least > 3)
F 03 Undervoltage or overvoltage
F 04 Premature flame recognition
F 05 Flame monitor (petrol heater) interrupt or short circuit
F 06 Temperature sensor interrupt or temperature sensor short circuit
F 07 Metering pump interrupt or metering pump short circuit
F 08 Fan motor interrupt or fan motor short circuit or fan motor overload or blocked
F 09 Glow plug interrupt or glow plug short circuit
F 10 Overheating
F 11 Overheating sensor interrupt or overheating sensor short circuit
F 12 Heater unit lock-out
F 14 Overheating sensor installed incorrectly
F 15 Setpoint generator short circuit

Regards
Chris

[arctictraveller]

Could it be air locked? Despite your trying to prime it, an air bubble could stop all flow. Can you run 12v directly to the pump, with the output hose run to a container? If the pump then runs continuously without pumping, either there is a blockage on the inlet side, or the pump is defective. Next I'd try running a hose directly into a a small container of fuel. Still no output? Bad pump. If it then pumps, the problem is prior to the pump. Just an idea.......................

[cthayn]

Guys,

Thanks for the ideas. After waiting a week for a response from Heatso or Webasto, your comments prompted me to remove the pump, connect it to a 12v source and do some benchtop testing.

After several attempts, I found a yellow piece of plastic in the intake port of the pump. The pump ships with a yellow plastic cover on each of the ports. It appears that in shipping or at some other time, the plastic cover was impacted and it cored a chunk of plastic that occluded the intake port.

Once the chunk of plastic was removed, the pump had no problem moving the fuel. I reinstalled the pump and the heater started on the first try.

I’m glad it was something simple, once I found the occlusion.

Thanks for the help.

[86Scotty]

Good to hear. Nothing like an old fashioned ‘fixed it myself’ story.

[arctictraveller]

Yup, nothing like an easy fix.