Waranty claim rejected for no good reason

My Solartherm 300 l geyser burst after 4 years. It had a 10 year warranty. WE Geysers rejected the claim because there were no covers over the vacuum breakers. According to them, \the vacuum breakers on the installation does not have lids/covers. According to the manufacturer this makes the installation non-compliant as the geyser will not drain the way it is suppose too."<br> <br> The plumber employed by the insurance company has expressed the opinion that the covers played no part in the operation of the geysers. I have had a look myself and there can be no link between the lack of these plastic covers and the geyser bursting.<br> <br> So beware"