Trumatic c3400 Warning lights

[Hazy-thoughts]

Can anyone help with a suspected problem with my Truma heater/boiler.
When in operation the red warning light flashes rapidly. The manual says that this denotes that the operating voltage is too high for the appliance. It has been working perfectly and has suddenly started this.

A little concerned I have turned it off, Any idea's anyone

 

[Hazy-thoughts]

Hi *****, yes I know it goes red when gas is low or 12v is not on, i have an operating manual and nothing else, it says

If red light flashes 1 x per second too little voltage to appliance, if flashing more rapidly (which it is) then voltage too high.

I have no idea what has caused it to suddenly start happening

And it is cold outside

 

[Deleted member 3011]

Disconnect shore supply so the battery charger is not working. Switch all the lights on for 10 minutes and then try the heater.
If it still shows high voltage, the problem is in the heater electronics. If the light doesn't flash then it may be a problem with the battery charger - either stuck on bulk charge or on equalise cycle, or could even be a high resistance cell in the battery causing the battery charger to malfunction.

If the battery voltage is 14.4V or less and the light still flashes, it is probably safe to ignore the alarm.
If the battery voltage is below say 11.8V, then the alarm is probably for low voltage rather than high.

Either way, you will need a semi-decent digital voltmeter with a 20V scale. Plenty available for a few quid that will be accurate enough for the job