Duratherm geysers and worthless warranty

This is the worst company ever. Their solar geysers are supposed to be guaranteed for 10 years. Mine is 4 years old and burst last week. They are now trying their utmost best to not honor the warranty. Many excuses. They take NO responsibility. They flatly refuse to send an assessor to come and assess the installation and leak. I've sent photos showing the leak and the solar pipes. I also sent email correspondence when the geyser was installed during November 2014. They still refuse to send out someone. Their warranty is thus worthless. The quality of their geysers is ***** in any case. I was supposed to get a booklet when the geyser was installed. That was not supp****. I did not sign any document stating that I understand the warranty and all underlying conditions - there is no advice record with my signature on it. Any warranty or guarantee should have such a record such that the company has proof that they explained everything to the client. This did not happen at all. Do NOT support this company. The warranty is worthless! Which company, in this day and age, is still of the opinion that the client is NOT king? Why don't they want to send someone out? Are they afraid they'll have to honor the warranty?