Help - Vaillant EcoMax Pro 18E

Minotaur · Sep 16, 2018

Tearing my left over hair out. Boiler is just not activating

Fault Code 11
Sub screen code - Flame picture with Electrical sign, Code 2

Symptoms
- On switching on Boiler - Slight ,i mean slight, jerk on fan as if it was
going to start

- Pump does not switch on ( pump checked, works)

Tried
1) Motherboard Changed
2) Voltage checked as per valliant Fault finding diagram

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Suspicious of Fan ?
If Fan is defective, would the pump Not switch on ?

Have explored all over and just cannot reach any decisive answers

My presumptions is on start up ( if there is a demand )
1) Pump Would switch on
2) Then Fan would start up ?

The LED status is showing Green

I have attached a document with the fault pics

Any pointers / solutions would be much appreciated. Am relatively new to this field and trying to find my way around ( slowly ) through fault finding

chris watkins · Sep 16, 2018

MI's state F11 = Connection fault between main PCB and interface; Faulty interface; Faulty main PCB (processor), Check fan

Hi Minotaur Welcome, You might not get much more help until you show GS Registered.

Minotaur · Sep 16, 2018

Hi - Yes - I went through all those process's ie Interface, new PCB etc. Although "Check Fan" is rather ambiguous

I am GS registered. Have entered my membership number. Unsure how else to show it ? Mind you, have only registered on to the site this morning