Waterhouse sells Poor Quality Pumps and won't refund me!

I bought the highest specification pump for my application (at a high cost too) from Chris in late July 2021. It failed in October 2021 and after much email communication, I proved to them that the pump did not run dry, like they imp**** (with pictures of my installation).

Then, instead of giving me a new pump, they offered my a second-hand pump with a shorter cable. I reluctantly agreed and installed this pump. It then failed in late December, whilst they were closed. I took the second pump to Waterhouse on the 18 January 2022, to get my money back as I lost faith in their pumps.

Chelcea had it checked out by their technician and confirmed it was a factory fault. She then offered me a 3rd, now brand new pump from the Waterhouse or Dragonfly brands. I refused to accept the offer, as I don't think either of these pumps are of the quality required for my application. The have similar design and construction materials.

Chelcea refused to refund me, but offered a credit instead, which also does not help me as I don't need spares etc. from them and they are located far away from my home (30km), so it was impractical.

Now I believe its unreasonable for me to accept a 3rd pump from them considering the history of their pumps and I am out of pocket because I bought a European manufactured, replacement pump which is working fine in my application.

I believe I am entitled to a full refund but they won't budge!