Hi, I'm not an electrician, but have been following this thread after searching for problems with Solarimmersion. Original problems with delivery, i.e. told it had been delivered, but 2 weeks later had not received it. Paid with MasterCard, so after initial delivery problems, used this to try to get money back. Unit arrived just before MasterCard contacted Solarimmersion, so proceeded with installation. Installed by electrician who recommended it, and had installed in his own home. Worked for 2 days, then stopped diverting to immersion heater, so obviously no hot water. Also, all the buttons would not work, so could not do factory reset, use override, or use any of the functions except set time. Contacted Solarimmersion and asked to return the unit. That was almost 3 weeks ago, and have tried to find out what is happening to it. Customer services are appalling, passed from one person to another, and never receive call-back if no one available. Still have option to get money back via MasterCard. Cost of installation was £80. Cost to uninstall it was £50. Cost of p&p was £20. Cost to reinstall it will be £50-£80, which will eat into payback time. So in light of those on here who have problems with the supplier, and of those who have got one installed and it is working well, is it worth continuing, or should I cut my losses and get unit costs back via MasterCard? Your thoughts and advice would be greatly appreciated.