i had used Deka heater DSP1 for 2 months..bought abt RM450.after a week usage the water is not hot.i call up the shop in SS17 SJ and Deka technician came 1 day after.actually the problem is my installer wiring.so the heater trips because of '2P2T'....now enjoying it.not noisy as joven last time.sleek design..simple operation.