PH advice on legal warranty on Composit Door

[Soir]

Had a new composite front door fitted less than 2 years ago. Door is made by solidor, but I bought it through Premier Frames UK.

Solidor happy to replace it but insist they need to go through Premier Frames UK.
Prem Frames was taken over by GAP (General All Purpose Holdings) last year.
Depot Manager at Premier Frames (Now GAP) happy to sort this out for me, but then states that the SEO has told him they do not have any liabilities for guarantees under products sold by previous company and can't/won't do anything now.

Trading Standards agree they not legally liable, but morally manufacturer should replace.

I have a front door which is supposed to last a lifetime and soon it will be unable to close/lock. I have young children and cannot risk leaving it open.

Any idea how I can get this sorted? any tips advice? (I've emailed several board members of GAP, and the SEO phoned me direct to relay the same bull... The manufacturer said will call me back, to no avail..)

[Simpo Two]

Sounds like you're dependent on their goodwill - of which they don't seem to have any.

When one company buys another sometimes the liabilities are taken on, sometimes not. Perhaps you could ask for proof that they were not?

[Soir]

Quick update: manufacturer (Solidor) have agreed to replace the door for free, however they want me to pay for and organise myself;
A joiner to remove all locks/letterplate/knocker, refit onto new door and install the door
A glazer to remove the glass and refit to new door

They essentially want to give me a basic carcass and for me to transfer all the bits over
I'm happy to bay for someone to install the door and move all the bits but having to get a glazer too is taking the Michael

Lock/knocker etc are easy to move but not the glass panels, is that not asking too much?!