Purchased our heat pump water heater 4 years ago when converting house to solar, unit works great, continuous hot water at any time of day, however in the past 3 years we have had to replace the pressure valve 3 times, and now today 20/11/2018 it looks like it has gone again, has now come to the stage that we will replace it with a off peak model, very disappointing.

Made the expensive move to a heat pump. Initially was happy, although the unit broke down at about the 18 month mark, warranty service just reset switch, without searching for tty h r reason. About 12 months after 5 year tank warranty ended, the unit failed completely (internal gas leak) Too expensive a purchase to only last 6 years.

I am not sure who designs builds and tests these things but after purchasing 3 units they have all failed. Way too noisy when they do work. I have had one unit replaced. a Condensor on another unit and the third unit has now failed twice. Feedback received by other owners confirms mine is not an unusual experience.
energy efficient
Too Noisy

Bought one of these to cut down on power bills. The first unit was delivered and installed OK, power consumption was light initially. After 18 months the power use gradually rose and the unit failed at two years. After inspection (the refrigerant charge had leaked) and Stiebel replaced the heater. Now the second heater is going the same way as the first, power use is rising, triple what it was a few months ago.

Refrigerant charge leaks.

After some communication hurdles, i have to say the Customer Service from Stiebel Eltron was excellent. Thanks to Simon Weatherburn and his team I had my problem resolved within 3 Days. I have a WWK 300 AH Solar hot water system that worked well providing our family with lots of Solar heated hot water. We had a hiccup & Simon and his team were quick to respond and i am one happy customer. I recommend Stiebel Eltron Solar Hot Water to all.
Lots of hot water and low running cost.