Eco Max pro heat only

[flesi]

Having a bit of an issue with above boiler. Boiler fires up till reaches 40-50 degrees then it just stops, no fault code. Seems like it's not modulating. Turned it off and on again and it does the same thing. Can anyone shed any light? Cheers

 

[jtsplumbing]

Poss faulty thermistor one on flow one on return, not sure what résistance readings you should get just ring Vaillant for information

 

[flesi]

Yeah possibly, I will check the reading. Cheers

 

[ambrosia]

try swapping the thermistors over, could be return thermistor is reading hotter than the flow

 

[flesi]

So far I tried adjusting the gas valve, tried new fan and electrodes. PCB is been changed by another engineer. No fault code. Am I missing smth? Usually vaillant are easy to fault find. Could have fit new boiler by now.

 

[Rabbitman]

First thing to check is that it's configured correctly it should only require doing if the display PCB has been changed (code no 23 to 26) but they have been known to wander off by themselves lol........ Then access the status codes to see what there set to, if it's a circulation problem I'd expect to see f24/25/26 although you could check the deltaT accross the fl & rt to confirm, hope this helps

 

[jonnyswamp]

You've varified all external controls working fine and keep calling for heat after boiler appears satisfied ?