AIBU to want them to replace it?

[Doowninthedumps]

Fridge freezer cost £180 new (basic model, all I could afford), freezer broke less than a year later and entire freezer full of food defrosted and needing thrown out. Repair man says non-fixable fault.

They have offered me £87 worth of refund, AIBU for thinking they should offer a full refund or replacement. AIBVU to think this is a crap offer since I'll have to replace the entire unit since a separate freezer will not fit in my tiny kitchen (and not to mention the cost of food thrown out)?

Should I wind my neck in?

Keep pushing them. Keep any evidence such as anything you sent them before the year expired as proof that you were trying to make contact with them for days before they actually replied. If it broke within a year you are entitled to have it repaired or replaced (but that's at the seller's discretion not yours), no question.

Trading standards can advise. The year warranty aside, things are meant to be fit for purpose and you would expect a fridge / freezer etc to have a life expectancy of more than 12 months.
Do you know what the fault is? If so, Google the cause. Send a signed for letter to head office stating that you will contact trading standards as the fault is X and not repairable, and the life expectancy of equivalent goods is (check online for answer).
Tell them you are disappointed with service received and ask them to resolve by replacing.