Beading wont bite with new DGU

[Teddy_Amok]

Hello, i hope u r all well. I received my new double glazing unit for upvc window yesterday. The old unit had failed. The new unit is the same dimensions as old unit but twice as heavy as it is toughened glass*2.

Whilst i found putting the beading back on the old unit (needed to measure) easy, I spent all day yesterday trying to put the beading back on once i installed the new unit.
The top left and bottom right corner beadings wont bite bit although the rest of the beading for top and bottom does. Ive tried fairy liquid, ive read every article on google i can get my hands on.

The upvc windows are about 10 years old. I can only guess that the depth of the new unit is slighly bigger in those 2 corners.
As far as i can see i have heeled and toed it correctly.

As i said, 50% of top and bottom do bite so along with the packers its solid enough to stay in place for a short time.

I bought the tools for completing this task so am annoyed at the prospect at the thought of calling a glazier to fit the beeding tomorrow. Also, tomorrow is my only day off for 2 weeks so would not be happy leaving the unit in as is for a long period.
As the unit is so heavy I want it to be secured properly.

Any help or advice would be greatly appreciated folks.

Kind regards,
Ted

 

[Notch7]

Why would the new unit be heavier?

Toughened glass is the same weight as annealed glass.

Do you mean your new glass is laminated 6.3mm instead of 4mm tough float glass?

I would start by checking the dg unit thickness, in a few places and see if its the correct thickness

 

[Teddy_Amok]

Well, when the people installed our windows and door, they told us that because the livingroom window and bedroom window is knee height they need to be toughened. I knew nothing about windows really but when the gentleman delivered the new unit yesterday I could tell straight away that the original window was not toughened glass. me and the wife had always thought that there was not a huge difference when we got original double glazing installed compared to single.

I was worried yesterday that because of the weight of the new unit (30kg) there would be an issue. I was worried in case there was a weight limit on our upvc window frames. Its something I had never heard of or considered.

I took some pics.

 

[Teddy_Amok]

Sorry about the marks on the upvc btw. Hand was bleeding

 

[God]

looks like a 4/20/4 unit. have you got a pic of the label.was your old unit 4/16/4

 

[ronniecabers]

Can't quite see the safety mark in your second picture ... bottom corner , circular mark, if its toughened it should say BSEN 12150. Can't remember the number for laminate off the top of my head. Looks , to me , like it could be the ' packers ' ( the plastic bits you toe and heeled it with ) are stopping that beading going back, if it was the thickness of the unit the bead wouldn't go in at all, unleews just the corners of the units are wider where the sealant has seeped under the glass, happens when toughened glass is bowed when its manufactured, just double check various widths down the unit, 1mm should be taken up by the rubber on the beading , but any more than that ....