# Opinions about 2 part heat pump hot water heaters (e.g., Sanco 2, Sanden)

**URL:** <https://boards.straightdope.com/t/opinions-about-2-part-heat-pump-hot-water-heaters-e-g-sanco-2-sanden/999583>\
**Category:** In My Humble Opinion\
**Created:** [March 29, 2024, 8:56pm UTC](https://boards.straightdope.com/t/opinions-about-2-part-heat-pump-hot-water-heaters-e-g-sanco-2-sanden/999583 "2024-03-29T20:56:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jharvey963](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jharvey963](https://boards.straightdope.com/u/jharvey963)\
**Post date:** [March 29, 2024, 8:56pm UTC](https://boards.straightdope.com/t/opinions-about-2-part-heat-pump-hot-water-heaters-e-g-sanco-2-sanden/999583/1 "2024-03-29T20:56:15Z")

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I have wanted a heat pump hot water heater for a while, but the closet it fits in is just too small for any of the existing (1 piece) units.

Just recently, I’ve noticed that there are now 2 piece units: the inside part is only a storage tank, outside is the heat pump unit. Cold water (or cold-ish) flows from the tank into the outside heat pump where it is heated, and returned to the tank as hot water. This design might actually allow me to get a heat pump water heater.

I’ve found 2 companies (that might actually be the same company) that supply these types of units: Sanco and Sanden. Is anyone familiar with these companies or these 2 piece water heaters? The Sanco unit I saw had an “Energy Guide” label saying yearly cost estimate to run is $127, which is excellent. It had a 43 gallon storage tank, and a first hour rating of 69 gallons. The heat pump is rated to work all the way down to -15 degrees. The Youtuber Matt Risinger (who makes home building videos) mentioned that he installed a Sanco unit in his house.

Some of the questions I have:

- How loud is the outside heat pump unit?
- Have you actually used / installed one? What is your experience with it?
- Do other companies provide 2 piece units?
- Are Sanco and Sanden the same company?
- If you have one, how did you order it, and who installed it for you?
- Do you know anyone who has had a bad or a good experience with it?
- What criteria would you use to judge a unit like this?

Thanks for your opinions,  
J.

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<div class="post-metadata">

**Author:** ![jharvey963](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jharvey963](https://boards.straightdope.com/u/jharvey963)\
**Post date:** [March 30, 2024, 4:37am UTC](https://boards.straightdope.com/t/opinions-about-2-part-heat-pump-hot-water-heaters-e-g-sanco-2-sanden/999583/2 "2024-03-30T04:37:06Z")

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I’ve just learned that Sanden is actually the name of the company, and Sanco is the name of their heat pump water heater.

J.