During the explanation session, I asked the plumber about changing the temperature of the boiler, which he said was impossible. In fact, checking the manual and playing with the controls, I found that it was possible. There are three settings for boiler temperature: high, medium and low. Also, there are three settings for the amount of hot water in the boiler: a full tank (460 litres), 100 l or 50 l.
The plumber didn't actually fit the boiler, so I don't completely blame him (although he shouldn't be telling people things are impossible when he just doesn't know how to do it), but the people who did fit the boiler also put in the underfloor heating, which they switched on to pump hot water throughthe whole time, and did not set the boiler to the maximum temperature, so it was both using expensive day time electricity, and running out on us when it came to bath time. So they didn't know how it worked either!
The idea behind the Eco Cute is basically to use cheap night time electricity, from 24-hour nuclear and gas-fired power stations, and not really anything to do with ecology or saving people money.
People with large households certainly get a good deal with their Eco Cutes, providing they don't run out of hot water. Meanwhile a lot of elderly couples, victimised by silver-tongued salesmen, find that their heating bills go up, on top of the investment of their savings into this new wonder, or worse still having been encouraged to take out a loan to pay for it. Over-dimensioned tanks with insufficient insulation incorrect settings.
The situation in Hokkaido is apparently that so many people are using Eco cutes that there is now a shortage of night time electricity.
