Ecotec Plus 428 CON Error - No communication to main board

[kurtuk]

I am getting an error CON on the display of my Vaillant Ecotec Plus 428. I have swtiched then off switched on but the error does not clear. I have looked at the manual and the error is "no communication to main board" and the cause is "connection error display main board".

The boiler was working fine before I noticed the error and I cannot imagine anything that happened that may have caused a problem.

Can anyone clarify what the actual problem is and what the remedy is?

 

[picasso]

Every time I have seen this on the display the boiler has needed a new board.

 

[Bunnyman]

New pcb

Untitled

• Bunnyman
• 26 Mar 2010
• 499

 

[bell824]

yup p.c.b failure.

 

[kurtuk]

thank you all - I was hoping the answer would be different!!

The actual boiler is only a few years old so is this a part that is likely to fail after such a short time or would something have caused it to do so?

Could there be an underlying problem that I should get checked out?

Also, is the board something that I should be able to buy and replace?

 

[Jordon]

Gunna get moaned at but call vaillent for a one off repair cost, the boards are dear so you connect it wrong it will be bad times.

 

[kurtuk]

took advice and agreed price with vaillant to repair and a few quid more to be covered for a year.

now there is another problem but i dont know if it is from the boiler or the programmer so need some advice before i call vaillant out again.

i have a sunuic select 207 XLS programmer connected to the boiler.

even when the programmer is off (not programmed "on" rather than power switched off) the boiler still kicks in and runs for a minute or so then switches off for a minute or so then starts again and continues through the cycle.

the codes on the boiler start from s.1, s.2, s.3, s.4, s.5, s.7 and sometimes s.8. s.1 to s.5 are normal working procedure but s.7 is "pump run over" and s.8 is "anti cycking mode". these dont sound good. the boiler starts around 39C and switches off at 67C (67C is the set high temp on the boiler).

question is, is there a problem with the programmer (switches boiler on when there is no call for it) or is there a problem with the boiler that it keeps switchin on, off?

 

[SA_UK]

Recently, my boiler started displaying a message saying "Communication Fault". I believe this shares the same underlying cause as the "Con Error". No amount of pressing the reset button seemed to clear the error. However, the following did work for me.

1. Press the power switch on the front of the boiler to turn the boiler off
2. Switch the power off at the fused spur (mains power switch)
3. Press the power button on the front of the boiler again but DO NOT switch the power back on at the fused spur
4. Wait for some time (30m - 1h)
5. Switch the power back on at the fused spur

If done correctly then the boiler should power on and the error should have cleared after executing step 5. If the above doesn't work then repeat but wait longer at step 4

 

[CBW]

I’ve a feeling this will be a temporary fix.

 

[JohnD]

Recently, my boiler started displaying a message saying "Communication Fault". I believe this shares the same underlying cause as the "Con Error". No amount of pressing the reset button seemed to clear the error. However, the following did work for me.

1. Press the power switch on the front of the boiler to turn the boiler off
2. Switch the power off at the fused spur (mains power switch)
3. Press the power button on the front of the boiler again but DO NOT switch the power back on at the fused spur
4. Wait for some time (30m - 1h)
5. Switch the power back on at the fused spur

If done correctly then the boiler should power on and the error should have cleared after executing step 5. If the above doesn't work then repeat but wait longer at step 4

If you reply to questions raised less than ten years ago, there is more chance that your posts will be helpful.

This one is from 2011.