Potterton Envoy problem

[boilkermansab]

Recently having problems with my envoy, the condensate was backing up and fllooding the boiler, so i tried cleaning the syphon but it was still the same.
Ended up buying a new one, however it seems to be doing the same and not letting the condense run away. But if i go to undo the drain pipe where it connects to the syphon it begins to run away. Seems as if it causes some sort of air lock??
Anyone else encounted this??
I know this boilers are not the best but we have had it 10 years and its only the 2nd time its let us down

 

[migoplumber]

make sure you havnt created a double syphon, if you have, it wont drain the 1st siphon until the height of water in trap 1 - equals the height of the trap depth in siphon 1 plus trap depth in siphon 2

 

[boilkermansab]

I can see what your getting at but how have i created a double syphon??


I deal with industrial boilers, so househould is not my forte!

 

[boilkermansab]

Anyone else know?
Really need some help

 

[RoryD]

The little black ribbed rubber connection is blocked (sounds like something for the weekend!!). There is more to check internally but seals MUST be replaced.