Interesting. In five years, we've never once had a frost problem, either in the fridge or freezer, with our Haier CFE633CWE. Model specific perhaps?
We got one of these freezers, the freezer may be frost free but the fridge is always frosty at the back. Tried it on all different settings and makes no difference. They sent us another one which did exactly the same thing, they then sent out an engineer who did nothing and just said it is a common problem. We just put up with it because got sick of the hassle.
As an alternative, there's also this Haier FF available at £239.99 delivered from Co-op Electrical (use £10 off voucher to get this price)... https://www.hotukdeals.com/deals/haier-frost-free-fridge-freezer-245-co-op-electrical-3162556 It's a slightly bigger fridge but a smaller freezer compartment. Importantly it also has a 'door open' alarm (useful if you have a wife like mine who never shuts any door properly!). Had our Haier FF running in our kitchen for the last five years. Makes the occasional gurgling noise but has been fault free throughout. Indeed have just bought another as a 'spare' because £240 is a ludicrously low price for a decent FF! Co-op delivery was super efficient arriving exactly when they said they would.