SANCO2™ High-Efficiency Heat Pump Water Heater
The Clear Path to Net Zero Energy.
Save Energy with the SANCO2™ Hot Water Heat Pump System
SANCO2 HEat Pump with 43, 83, and 119 Gallon Tanks
5x more efficient than traditional electric water heater
Allows use of off-peak power
Greater first hour rating than all heat pump water heaters
Faster recovery after hot water draw
Hot water production down to -20°F & below
Up to 150°F delivered hot water temperature
Efficient Operation: How the SANCO2 System Works
The SANCO2™ Heat Pump Water Heater is a two-part system consisting of a tank (usually placed indoors) and a heat pump unit (usually placed outdoors, up to 66 ft away from the tank). The heat pump works like a reverse air-conditioner, drawing heat energy from the atmosphere and applying it to water from the tank. This technology is already in wide use in industrial applications as well as residential water heaters in countries like Japan and Australia. These systems were marketed under the Sanden name until 2020 when it moved to the name SANCO2.
The SANCO2™ works just like a conventional heat pump, except that it uses CO2 as a refrigerant. Due to the unique properties of CO2, the SANCO2 operates very efficiently in a wide range of temperatures. It is able to extract heat from the air all the way down to -20°F and beyond in a single heating stage, raising the water temp to 150°F at .3 gallons/minute. The result is a system that requires radically less electricity to heat water when compared to conventional hot water systems and works without a backup coil in a very wide range of climates.
While the SANCO2 system is a perfect choice to replace an existing gas or electric hot water tank in any residential or multifamily application, the ability to work at low exterior temperatures and still supply hot water at 150°F means the same system can be the total solution for today's new low energy homes.
The SANCO2 Uses CO2 As a Refrigerant which is Ozone Friendly & Doesn’t Contribute to Global Warming
A heat pump uses a small amount of energy to move heat from one location to another. In the SANCO2 system heat in the air is absorbed by a natural refrigerant, CO2, which is ozone friendly and does not contribute to global warming.
The warm gaseous refrigerant is circulated in the system via a compressor. As it passes through the compressor, its pressure rises, as does its temperature. This hot refrigerant then passes through a heat exchanger to heat the water, which is then pumped to the storage tank.
The Combi-System : DHW plus Space Conditioning
With a capacity to deliver 15,000 btu/hr, a SANCO2 heat pump hot water heater can be designed into a system that delivers all of the domestic hot water (DHW) as well as heated water for space conditioning. This is accomplished with one circuit feeding a DHW mixing valve to reduce the temps to 120°F, and another supplying a standard heat exchanger supplying hot water radiators or radiant slabs.
For homes with a design temp of 12°F or higher, and a heat load of 8kbtu/hr or less, this can be the entire DHW and space conditioning system. Additional on demand hot water heater systems can be added into a design for homes with larger heat loads or used back up systems to provide added capacity for extreme weather events or large homes where all but the coldest days can be supplied by the default Sanden system. It's important to note that this COMBI technology is still in the development phase. As features are improved and more projects report success, the 8kbtu heat load can be increased, and lower design temps added, based on capacity improvements and project results.
Multifamily DHW Projects and the New 119-gallon Tank
The efficiency of the SANCO2 is attractive for new multifamily projects but the offering of 43 and 83-gallon tanks are tough to fit into a building since space is tight. With a new 119 to 505-gallon tanks, things change. Large building designs have been developed and tested in the last few years that gang together these units into heat pump arrays serving larger primary storage. For more about large buildings, please see WaterDrop.
Ten years of CO2 Heat Pump Success and Counting...
While heat pumps using CO2 as a refrigerant are new to us, Sanden has been producing these systems in their original market of Japan for close to a decade. The culture of Japan still enjoys bathing in a hot water bath as a relaxing and healing experience. As the ability of the Sanden CO2 heat pump (now SANCO2) became known to efficiently deliver a high volume of very hot water, Japan embraced and developed the technology as the preferred method to supply the large amounts of hot water for a "bathing culture".
Success in Japan brought success to the rest of the world with the movement of the majority of European and Asian vending machines and other refrigeration units moving quickly to CO2 heat pumps as the "new way to lower operating costs".
These systems are in stock and available for next day shipment in both our Tumwater, WA and Vancouver BC locations.
SANCO2 Frequently Asked Questions
+ What makes a SANCO2 Heat Pump Water Heater different from other water heaters?
Traditional water heaters use inefficient heating elements (electric resistance) burn fossil fuels (Natural gas/propane) or use high global warming potential refrigerant gases (traditional heat pump water heaters) to produce hot water. The Sanden HPWH uses CO2 as its refrigerant, which allows it to achieve 30-40% greater efficiency and work in a wider temperature range than even the most efficient traditional heat pump water heaters.
+ What is the operational temperature range?
The SANCO2 HPWH works in temperatures from -20F to 110F
+ When will I make my money back?
Based on an average $0.124/kwh we estimate you will see a return on investment, depending on usage and climate, within 5 years.
+ Are there any rebates available?
Most utility companies in the Pacific Northwest have rebates available, and you can search by zip code at https://hotwatersolutionsnw.org/. For further information, please contact your local utility provider.
+ What unit sizes are available?
The outdoor unit comes in one size, but feeds a varying size tank. We have 43-gallon, 83-gallon, and 119-gallon hot water tanks available.
+ How much hot water can this unit deliver?
The 43 Gallon tanks have a 1st hour hot water delivery rating of 69 gallons, while the 83 gallon tanks deliver 115 gallons in the first hour. The 119 gallon tanks deliver 135 gallons of hot water in the first hour.
+ What is the hot water recovery rate?
The SANCO2 heat pump is able to produce 16 to 23 GPH of 131- to 150-degree Fahrenheit water (depending on heat pump settings).
+ How many BTUs?
The heat pump delivers 15,400 BTU/hr.
+ What are the dimensions for the heat pump and tank?
Please refer to the SANCO2 specifications sheet and be mindful of the hot water tank model numbers.
+ What are the electrical installation requirements for the SANC02?
The heat pump requires a dedicated 15a 208/230v – 1Ph – 60Hz connection. The tank is non-powered. Please refer to the installation manual for further information.
+ What is the coefficient of performance (COP) for the Sanden system?
Dependent on the ambient temperature, it ranges between 2 and above 5. You will see higher efficiencies with warmer weather and colder incoming water.
+ How do we protect the water lines from freezing?
Insulation on the outdoor water lines is required, and a heat trace kit is recommended.
+ Can the SANCO2 be used as a combination domestic hot water and radiant heating system (Combi)?
Certainly. Your heat load must be less than 8,000btu/hr with a design temperature of 12F above, and SANC02 recommends you use at least 20 Gal of domestic hot water per day to maintain tank stratification and efficiency.
+ What are the requirements/limitations in a combination setup?
The requirements and limitations are as follows:
SANCO2 HPWHs are not designed for use in heating-only applications. They must be used as ONLY domestic hot water heaters or combination DHW and heating. Sanden recommends using at least 20 gal of domestic hot water per day maintain hot/cold stratification in the tank. This stratification is required to achieve high COP.
The SANC02 combination system using a single heat pump is not designed to heat spaces requiring more than 8000 btu/hr (around 2500w).
In cases where there is additional load being met by backup or additional heat sources, the system can employ DHW priority through the Taco X Block. This feature will maintain the DHW temperature during periods when the Sanden cannot keep up with the heating demand.
Additionally, two heat pumps can service one 119-gallon tank in a combi-system. This can increase the capacity for heat load to 16,000btu/hr.
SANCO2 requires that the domestic hot water and space heating loops be separated by a heat exchanger, specifically the Taco X Pump Block. A heat source protection sensor is also required to be used between the heat exchanger and the hot water tank.
+ Do you have any recommended installers?
We are currently working on developing our network of recommended installers for the Pacific Northwest. Fortunately, the Sanden has very simple installation requirements and can be done by any licensed plumber.
+ Are the SANCO2 Systems approved?
The SANCO2 systems have both UL and CSA Certification
Small Planet Supply Blog Posts aboud SANCO2 HPWHs
How a SANCO2 System Works in Less Than a Minute
SANC02 Questions? Phone Consultation Appointments are Available
Have some questions about the SANC02 system and want to feel like you’ll have enough time to have them all answered? We’re offering complimentary consultations with one of our specialists. You can schedule it using the button below.
Shop SANCO2 heat pumps and accessories at our Small Planet Supply online store. Click the icon for your country to shop SANCO2 products:
New SANCO2 installation video for simple residential applications.
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SANCO2 Information
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SANC02 - Down Under
Three videos from market development work in Australia: Introducing the concept, saving money, environmental impact of a heat pump using CO2 as the refrigerant.
“As a HVAC service person, these units hands down out perform any other heat pump water heater and the warranty was another reason to buy also. Highly recommended.””
Additional Resource Pages and Specification Links
Learn more about SANCO2 at http://www.eco2waterheater.com
Learn more about our network of advisors and installers
SANCO2 Heat Pump Water Heaters were a paradigm shifter when Small Planet Supply began carrying them in 2017. It seemed incredible that a water heater could achieve a COP of up to five while using a natural refrigerant with a GWP of less than one. The ability of a SANCO2 heat pump to produce an abundance of hot water began to spark the imagination of homeowners, innovators, and mechanical system designers alike. This blog post highlights three ways to utilize a SANCO2 in projects of all sizes, from smallest to biggest.