Don't bother buying from them, geyser burst and they want me to pay for installation

Had a heat tech geyser installed as a replacement +- 18 months ago, no end of problems with it, all repairs being for my personal account. Geyser bursts and when installer arrives they refuse to install as it needs to be installed via the roof. No comms from the supplier up front, similarly not sure why i must pay additional costs to install a burst geyser when the issue was created by the installer. I was told that i should "read the terms and conditions" in the document from when the product was installed. No focus on customer service whatsoever.