Vaillant ecotec 418 F72 F83 faults

[ianmcd]

try closing it back down just a turn or so and see if it changes anything, are you sure its not set at 80 and you are getting 75 ?

 

[7up1110]

try closing it back down just a turn or so and see if it changes anything, are you sure its not set at 80 and you are getting 75 ?

Thanks I tried it but it didn't really do anything, it seems to want to work after I put it back how it was

and yesterday afternoon fired up with no fault after I'd had to reset it all in the morning but now seems to run for an hour or so get all the rads hot but stops pumping to them before it reaches the demand from the start, the n the boiler temp slowly rises until I get an f20 fault for an over heat let it cool right down and its fine again. I cant feel any heat in any of the bypass pipe work. Would the fact adjusting the bypass has helped suggest the main issue is that valve?

 

[oscar_diy]

Hi did you ever manage to solve this? I'm having the same issue

 

[Johntheo5]

Have you the same circ pump, the Grundfos alpha?, if so, ensure its NOT on Auto.

 

[S987]

Did anyone get to the bottom of this? Same scenario, valiant ecotec plus430 installed only 4 months ago been fine until its got cold now (installed in September, now in Jan) and now it’s repeatedly throwing up f83, f72, f20 faults and requires reset to get going in the mornings.

 

[Stuckinarut]

Have you had anyone in to look at it? Have you had your unvented cylinder serviced?