Unable to adjust co2 readings vaillant boiler

[Gasssssssss]

Unable to adjust co2 readings on a a vaillant ecotec boiler it’s an lpg model I’m currently getting 0.0004 ratio, can’t get a higher co2 percentage than 8.6% (minimum being 9.7 without cover) and the ppm is around 40

Have tried new gas valve new Venturi and new pcb. I’ve cleaned burner and condensate pot and checked flue integrity which is coming back spot on the gas inlet supply is correct aswell

Have called technical help at vaillant but they are about as much use as a chocolate teapot

 

[Deleted member 120897]

Are you adjusting the correct bit, and giving it time to settle?

 

[Gasssssssss]

Yeah I’ve been trying to adjust it but it won’t go higher it will go lower but The MI say the allowances for co with no cover is 9.7-10.7 for lpg models this is the problem I’m facing

 

[ShaunCorbs]

What’s the temp of the flow and return ?

 

[Deleted member 120897]

Are you doing it in P1, P2 and checking P1 again?