We have four [4] apollo geysers installed on different buildings on our property 2 x 100lt, 1 x 200lt, 1 x 300lt. We have replaced the 300lt for the 3rd time since 2018, the element band thermostat keeps burning out and then eventually the tank bursts. we replaced the current one in December 2025, we rewired it from a different building with a new geyser wise control box, thermostat and titanuim element, we replaced the element and thermostat on 21st January because it burnt out and was shocking at the taps, it worked well until yesterday 15th February, it started shocking at he taps again. the control box is set at 65degrees, but it always boils to 85/90degrees. please assist