all Wooster green style boilers have facility to fit the flu externally without the need to work outside on a scaffold this simply involves pushing the flu through the wall and pulling it back to the wall to create an airtight seal this reduces the need again for the work in the Heights regulations I'm now going to demonstrate how easy it is to perform this simple routine first part the job is to measure from the outer wall to the centerline of the flow this will then determine how far we need to extend the flew out to get the collar to see it against the wall now we've got the dimension we require we get the flu extend it out to maximum distance taking our tape measure close the flue back up until we get the center of the flue in line with our maximum measurement required I now fix the two halves that flew together I've installed the inner sealing ring for the flue I'm now gonna apply this aluminum tape which helps to seal the flue up and make it easy to slide the flu through the cavity of the wall I'm installing it once we take the flow what we're going to do his story's outer ring here on to the edge of the flue there was a look at the top that needs to locate in that notch here what we need to make sure is that the the ridge here in this flue seal lines up with this Ridge here in the actual flow when they're lined up correctly is perfectly positioned to reseal the flue to the building when installing the flew from inside it's important to make sure the hole you drill is 150 millimeters when installing on a single brick wall cutting the flue down isn't always necessary the flue simply slides apart we then remove these two screws here and here I removed this section once we remove the screws simply take out this section here and replace it with the end turret section we then put the screws back in holding this piece to the turret if you want to flew sideways we are going through a very large wall and this short float isn't long enough we also do another option on flues this flew here is still telescopic and goes from five hundred and seventy millimeters of de maximum of seven hundred and ninety millimeters which ever flew option you use all three of these variants can be used internally pushing the flew ring through the wall without a need to use it scaffolding