Here is how I did the test. Set the thermostat to 60 degrees and let it heat until stopped, measure the temp on the kitchen tap. It was 51.5 deg. Cut the power and not to use any hot water for 24 hours. Measured the temp on the same tap again, it was 43.5 deg. Environment temp was around 18 deg, though it will be higher in the closet.
So the 24 hours temp loss is about 8 deg, for 135L of water it is about 1.26KWH. (4.2*8*135*1000*1/3600*1/1000) Considering during normal use the temp will be higher in average, so let's say the normal daily heat loss is 1.5KWH max.
So is that figure normal for a 2001 year model? If I were to add a wrap on that tank, can I expect the heat loss will be cut by half or anything? Cheers.
