What I have to say is absolutely objective and strict, especially after four years, so I can judge very objectively. In northern Greece, in a maisonette by the sea, exposed to salt and frequent bad weather with strong winds and southerlies, there is not a trace of corrosion or rust, absolutely nothing (holiday home). In winter, when we had to do interior work at the end of November, I always had hot water, even at midnight... Yes, really. In contrast to the Elco I bought for my main residence (about a year later) with the motto "Harnessing the Sun," which is ok but absolutely nothing like the Calpak... Definitely Calpak, and I won't risk getting the Mark 5 next time, but again the Mark 4... Incredible... Come Back 14/2/26 and yet it lasted over a decade with only one service during its lifetime in a marine environment, meaning I didn't maintain it well, but still it kept going and hot water even in winter!!!... Don't hesitate, buy without reservations.

This review is being made 22 months after the purchase of the CALPAK Mark 4, which was made in late September 2020 from the company KOKOTAS (the transaction was excellent & thank you very much once again). I delayed the review because I wanted to test the durability, specifications, and quality of this product over time. Well, yes! If I tell you that in 22 months I only turned on the electric water heater once, would you believe me? Even in winter - with 4+ cloudy days - I have hot water. Not naturally hot after 4 days of continuous cloudiness and nighttime temperatures below 8, but I have satisfactorily warm water. As for the summer months? It boils, steams, and fumes... Very hot water!! In conclusion, I am completely satisfied with the purchase and I believe I will have peace of mind for many more years.