vaillant ecotec plus 831 with S53 persists after heat exchanger swapout

[jortijn]

Hi all,
I got an issue that the boiler goes in S53 mode and the hot water goes cold.
after suggestions here I have swapped out my heat exchanger for an origional vaillant heat exchanger however this has not made any change and the water goes cold after a few minutes.
I checked the diverter valve and removed the motor bit and put it in HW still S53.
I checked the temperature sensors and measured them for resistance that seems all fine as well.
I checked the pump this seems all to be clean.
Central heating is happily working and haven't seen any problems with that.
please let me know if you have any idea's
Many thanks

 

[Agile]

A DIYer should not be opening that model of boiler as the outer cover forms the room sealed part of the design.

You need a competent boiler engineer.

Tony

 

[Dan Robinson]

Another bloody thread on the same boiler problem?