I am working professionally with a lot of heat pump water heaters (HPWH). It looks like we have a wave of 4th generation HPWH that have hit the market in roughly 2009.
What are your thoughts about the following models? I have added my thoughts, but would like to see if you have installed any of them? Do you have a different opinion/experience?
- Rheem was the first company to come out with the Rheem HP50. The product is so lousy it is not even funny. The noise level is at 68 decibels, vibration from the compressor that is transferred to wall structures through water heater earthquake strapping, and poor recovery once the tank has run through all of its hot water. The manufacturer even had to go back and change the dip tube to prevent the hot water stratification in the tank not to be destroyed. I had to go back on a bunch of jobs and pull them back out and replace them with something else.
- GE Geospring seems to be a good product. The have managed to leave the water inlet and water outlet connections to stay at the top of the tank. This eliminates the need to rework the water supply connections. I like the sound of the water heater....estimated at 55-58 decibels. It is probably the only DIY product out on the market. If I had to guess I would say that 8 out of 10 HPWH installations in the US are made with the Geospring.
- AirGenerate AirTap Hybrid water heaters. The product has won a couple of times the US Department of Energy Solar Decathlon with their add-on A7 HPWH. They have released two full-on integrated HPWHs the AirGenerate ATI50 and ATI66. The ATI66 has won the US DOE solar decathlon hot water contest in 2011. I like the stainless steel tank (should eliminate corrosion), the duct work (allowing for the routing of cold air to the outside), and 48 decibels sound level when it is operating. It is also supposed to work better in colder climates and have a temperature cut-off point of 20 degrees Fahrenheit. Besides reading about it I have not seen one in real life so far.
- Last but not least with have the AO Smith Voltex...I do not know a lot about this one at all. I have not seen an installation. I only heard that it is pretty expensive.