Truma fault codes

[aandy]

My Truma Combi 4E has recently become very reluctant to operate on gas, though fine on electric.The fan initially runs as normal but a few moments after the speed increases (ie when it should light) it stops. The LED flashes red and the display shows fault code 6. I've tried switching off and on again repeatedly - with delays varying from a few seconds to 30 minutes - to no avail, but it has (so far) always lit first time after moving the van, even if only over a short distance. Once it has lit it performs faultlessly for the rest of the day, but the next morning we are back where we started. The leisure batteries are showing around 12.5v and all other gas appliances are working as they should.

 

I have tried to book it in for repair but I can't find anyone who can look at it until the middle of May, which is a bit of a nuisance as I was planning to go to France next week. I'm tempted to go anyway, as I move the van most days and even even if it packs up altogether I shouldn't need heating and boiling a kettle for a wash is not the greatest of hardships. However, I'd feel happier if I had some idea of what is wrong and whether it is likely to get worse. Any thoughts?

 

Andy

[Keithl]

From this download (the first Google hit)...

 

http://users.telenet.be/S-cargo/manuals/bcl_769_2_1_0_en.pdf

 

it states "Current for combustion air motor too high" for code 6. Is this the code you are seeing?

 

My assumption would be you may either have a stiff or seizing blower motor or your batteries are failing and cannot deliver the current/voltage required.

 

Have you tried running the engine and re-starting the heater (if you can) or if not run the engine for 10 - 15 minutes then switch off and try starting the heater.

 

Can you monitor battery voltage when you try to start the heater, this may give you a clue to what is happening.

 

Keith.

[AlanS]

I had a look at the fault code list and it shows the following :-

 

Code 6 or Flash Code s,s,s,s,s,l,l,s : -

1. Current for combustion air motor too high

2. Combustion air motor or cable harness defective

 

Action:-

1. Check / replace combustion air motor

2. Check / replace cable harness

3. Replace electronic PCB

 

Why is your battery voltage as low as it is ? Have you tried the heater on gas when hooked up to mains supply ? (I know you have said it is fine on electric though).

 

Have you checked that there is nothing blocking the combustion air inlet on the outside of the MH ?

 

Alan

[aandy]

Thanks for the replies. My search technique is obviously not up to scratch, as I didn't find the code list after trawling through five pages of results.

 

I know 12.5v isn't top notch, but as I'm using conventional batteries (flooded?) is it that bad? They're only one year old, and they've never shown more than around 12.6 once they've settled down after charging. That said, I did wonder about the batteries as the boiler works fine after a run and on one occasion I did get it going by connecting to the mains. However, once it does run it continues to relight when required, even at night when other demands on the batteries would bring the voltage down further. Last night, for example, after a couple of days off grid it was re-lighting when the batteries were showing only 12.3v.

 

I took the flue cover off and both inlet and exhaust were clear for as far as I could see.

 

 

[colin]

'action2- replace cable', or as I had to do wriggle cable at boiler end and at control panel end, worked for me.