Webasto Heater Tripping Issue

[Shaun Witts]

My Webasto Airtop 2000 STC petrol heater has a habit of tripping during the night. This happened twice last night, and generally seems to happen at least once a week.

The LED in the centre of the rotary controller gives two long flashes after a burst of fast flashes indicating an error code of F 02: "Flame failure (at least > 3)".

It usually resets if I turn it off for a while, and then back on, but I don't want to be waking up in the night to do that every time I sleep in it (2 or 3 times a week usually).

Can anyone shed a light on whether this is normal behaviour and to be expected, or whether I have a problem (my van was converted just last November).

Any help much appreciated, than you.

 

[oldiebut goodie]

Was it installed by a pukka Webasto dealer?

1) Check for fault in air intake and exhaust systems + check for restrictions, fluffy toys/pieces of paper etc in hot air pipes. Insufficient combustion air can choke it as can exhaust blockage.

2) Check for fault in fuel system.
Check that the fuel filter is full - if air is present it can lead to flame out
Check that the fuel line rises from the pump to the heater otherwise airlock can form in loops. ( On petrol heaters there absolutely must not be a downward loop from the pump to heater, diesels can have it but it is still preferable to not have it ) Any joints at the rubber connectors must not have gaps between the spigot and the fuel line as air locks can form there. ie the fuel line must be fully inserted into the joint so that it touches the other internal piece.

3) Check fuel pump - check that the connector is fully home, it can be tight when new. Resistance across the terminals on the fuel pump should be around 8 - 10Ω

4) Electrical check of glow plug: ( This is used as a flame monitor on diesels )
Check glow pin resistance:
Glow plug: 12 V (red)
Resistance
at 25 °C: 0.263 - 0.323 ohms
Test current: < 5 mA
I use a 4 wire meter for testing these - a standard multimeter has insufficient resolution to read these correctly.

5) Check flame monitor pin on petrol models:
Cold test:
Resistance at 25 °C: 2.6 - 3.4 ohms
Test current: < 5 mA
Hot test:
Resistance at 800 – 1000 °C: 12 - 15 ohms
Test current: < 5 mA
(ceramic rod red-hot over length of approx. 20 mm)

I've attached one manual so that you can check that the installation was correctly carried out and the other is here

Fitting Eberspacher D2 - My Experience

Hi All, Not sure if this is of use but I took a few pictures as I fitted my D2 diesel heater, may help people having a go themselves. I’m not a pro at fitting these and this is the first I have done, any criticism is welcome. For reference this is the underslung T6 specific kit and I’m...

www.t6forum.com

 

[Shaun Witts]

Was it installed by a pukka Webasto dealer?

Thanks for the very detailed response and links to those manuals. I already had the Workshop manual, but not the Installation one.
The conversion, and Webasto installation, was carried out by Exploria, who claim to use Webasto trained technicians. It is installed under the floor, and uses OEM ducts in the drivers doorstep and B pillar.
As it has done this for a while, and it was installed only a few months ago, I am minded to get Exploria to look at it. Their initial response is that this would only normally happen if the fuel has been run low, and I have run the van down to a range of about 20 - 30 miles occasionally. But I'd like to think that if the engine can get fuel the heater can?
I'll have to get under the van and remove all the shielding to get a look at it, but it's going in for an LPG conversion this weekend, so I'm not sure when I'll be able to do that.

Thanks again for the advice.

 

[Spaghetti]

I have a Webasto Air Top 2000STC and I’ve not had a flame out error. It has refused to ignite once, but it went OK the next time though.

I have heard that the fuel pickup is higher for the heater, so as not to leave you stranded with no fuel for driving, and there could therefore be a grain of truth in what the installer is telling you.

 

[andys]

Yes they're supposed to stop working at low fuel level so you don't get stranded as @Spaghettiboy78 says

 

[Shaun Witts]

Yes they're supposed to stop working at low fuel level so you don't get stranded as @Spaghettiboy78 says

Hmmm, but does that also equate to air in the system and problems thereafter?
I had a brim full fuel tank last night, and don't think I've ever run the heater when the tank was empty (how low is too low?), but I have tried the "how far can I go on a tank" game and put nearly 75 litres in the 80 litre tank when I filled it.

 

[oldiebut goodie]

If you look in the last section of the installation manual you will see the size of the tank pipe - it should be inserted in the in tank lift pump and doesn't reach to the bottom. This is to leave enough fuel to get the van started and avoid debris being sucked in as the filter is usually installed just before the fuel pump for ease of access.
There is a very good chance that you have run the tank down and allowed air to enter the pipe - it can take a very long time to clear it all out of the fuel line system with normal running. I use a 12v/24v pulse generator to prime fuel lines correctly.

 

[Shaun Witts]

There is a very good chance that you have run the tank down and allowed air to enter the pipe - it can take a very long time to clear it all out of the fuel line system with normal running. I use a 12v/24v pulse generator to prime fuel lines correctly.

Ahh, bummer.
Every day is a school day, as they say.