That's right Kevin. There are two ways to make the sealed unit "Hot Melt and "Cold Melt"
The Company who fitted mine bleated on about how the Hot Melt was the best way " Yeah Right" He made the sealed units himself and bought the frames from a Supplier.
Nothing wrong with the frames they still look good. But on inspection now, most of the drain holes on the frames were blocked by architrave or upvc bead/trim fitted around the frame. Hence, Bad fitting & Crap Sealed Units. Without a lie every single unit has blown. I will get around to re-fitting the units but will also need to refit most if not all of trim around the frames.
The other factor in units blowing is the type of frame. Woodgrain are more suspect to blowing if they are exposed to the sun for long periods e.g "South Facing Windows". Some advice I was given was to go with white as obviously white disperse the heat better. Not sure if there is any substance to this but is does sound plausible.
I have a custy at the moment who has asked me to stop cleaning two of her windows as she wants them to dry out. I know she suspects WFP. All Woodgrain Frames, two at the front are South Facing. :
These units had already gone before I started cleaning them but failed to mention it when I quoted.
I do point out now when quoting any units that have blown. I tell them they can go at anytime and tell them of my own experience. Hopefully to quell any potential claims
It does sound like this is going to be an ongoing accusation against WFP and maybe one day some scientific proof might come to light and prove WFP to be a cause. If it does, them ebay will be full of S/H WFP systems for sale. Going very cheap
Wayne