In a another recent thread I noted how I'd corrected the calibration of my immersion thermostat to store more energy using my DIY PV diverter as the factory setting was quite a bit out and switched off the immersion well before reaching the temperature setpoint. It now max's out at 75oC as promised on the dial.   But I'm still very unhappy with the results I'm getting. Evidently due to stratification, the water leaving the top of the cylinder can be as high as 75oC while the point whe