Frequently Asked Questions about the Sanden "Eco®" Hot Water Heat Pump
1 - Is the Sanden "Eco®" Hot Water Heat Pump System an energy efficient hot water system? How does it compare to a conventional electric hot water system?
You can save up to 80% of your conventional electric hot water energy costs! The Sanden "Eco®" Hot Water Heat Pump System uses only 20% of the energy required by an electric storage hot water system
2 - What are the benefits of the Sanden "Eco®" Hot Water Heat Pump System?
Not only does a Sanden "Eco®" Hot Water Heat Pump System help save on energy costs, it also delivers:
(a) The Heat Pump Unit
3 - How does a heat pump hot water system work?
The Sanden "Eco®" Hot Water Heat Pump System operates like a refrigerator in reverse. It contains a fan that forces air through an evaporator that contains a refrigerant. The heat in the air passes through the evaporator and is absorbed by a natural refrigerant, R744 (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 finally pumped to the storage tank
4 - Which hot water system should I choose?
Sanden has 4 hot water systems to choose from, model numbers
Please speak to us about making the best choice for your needs and location.
5 - I don’t understand the use of a CO2 refrigerant by the Sanden "Eco®" Hot Water Heat Pump System. Isn’t CO2 a greenhouse gas and therefore harmful to the environment?
Yes, but CO2 has a Global Warming Potential of 1. Carbon dioxide is the baseline measurement of how it will contribute to global warming for a given mass.
Our system utilizes less than 1 kg of R744 (CO2) as a refrigerant contained in a closed system at the factory. The installer does not need to charge the heat pump on site.
6 - Why does Sanden "Eco®" Hot Water Heat Pump System use CO2 as a refrigerant?
7 - What is the noise level of the Sanden "Eco®" Hot Water Heat Pump System?
The unit is rated at 38dB, which is almost silent. By comparison, a whisper is around 30dB and inside a library is approximately 40dB.
8 - What is the life expectancy of the Sanden "Eco®" Hot Water Heat Pump System?
The Sanden HWHP is designed to last for 15 years. The high quality, weather resistant construction of the "Eco®" Hot Water Heat Pump System outdoor module carries a warranty of 3 years, whereas the high quality, extra long life stainless steel storage tank carries a class leading 15 year warranty
9 - At what temperatures will the Sanden "Eco®" Hot Water Heat Pump System operate effectively?
The Sanden HWHP will operate effectively between minus 10 and plus 43 degrees C, without the need for an electric booster element. It is also fitted with in built freeze protection, making it suitable for all climates
10 - Does the Sanden Eco® Hot Water Heat Pump require the assistance of an electric booster element to heat water, when outside ambient temperatures are very low?
No, unlike other competitor HWHP systems, the Sanden Eco® HWHP system does not require an electric booster element
11 - Can I operate the Sanden "Eco®" Hot Water Heat Pump System on Off-Peak Tariffs?
Yes, please refer to the Installation Manual for details. There are no special settings for off peak connection. Simply ensure that the off peak tariff supplies a minimum of 5 hours continuous power to the Sanden HWHP.
12 - What are RECs and STCs and what are they worth?
The purchase and installation of a Sanden "Eco®" Hot Water Heat Pump System entitles you to Small-scale Technology Certificates (STCs) – formerly known as Renewable Energy Certificates (RECs). For more information: visit www.climatechange.gov.au and www.cleanenergyregulator.gov.au
We can give you or your installer advice on current rebates as these can change.
The Sanden HWHP achieves the highest level of STCs of any hot water heat pump, currently available in Australia, and these are as below:
1 - Is the Sanden "Eco®" Hot Water Heat Pump System an energy efficient hot water system? How does it compare to a conventional electric hot water system?
You can save up to 80% of your conventional electric hot water energy costs! The Sanden "Eco®" Hot Water Heat Pump System uses only 20% of the energy required by an electric storage hot water system
2 - What are the benefits of the Sanden "Eco®" Hot Water Heat Pump System?
Not only does a Sanden "Eco®" Hot Water Heat Pump System help save on energy costs, it also delivers:
(a) The Heat Pump Unit
- Innovative technology -- up to 50% faster heat recovery than currently available Hot Water Heat Pumps.
- Industry leading quality & performance, with the highest level of STC values of currently available Hot Water Heat Pumps.
- Class leading warranties, backed by Sanden’s 30 years of operation in Australia.
- High quality, extra long life duplex stainless steel cylinder.
- Four different capacities available, 160l, 250l, 300l and 315l, all fully insulated for minimal heat loss)
- Fully insulated for extremely low heat loss
- Safety pressure and temperature relief valve
- Mains pressure rated
3 - How does a heat pump hot water system work?
The Sanden "Eco®" Hot Water Heat Pump System operates like a refrigerator in reverse. It contains a fan that forces air through an evaporator that contains a refrigerant. The heat in the air passes through the evaporator and is absorbed by a natural refrigerant, R744 (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 finally pumped to the storage tank
4 - Which hot water system should I choose?
Sanden has 4 hot water systems to choose from, model numbers
- GAUS–160FQS has a tank size of 160L, to suit 2-4 person household, ideal for units & townhouses, (note: continuous tarrif only
- GAUS–250FQS has a tank size of 250L to suit 3-5 person household, (on & off peak tarrifs)
- GAUS-300FQS has a tank size of 300L to suit 4-6 person household (on & off peak tarrifs)
- GAUS-315FQS has a tank size of 315L to suit 4-6 person household (on & off peak tarrifs)
- GAUS-315FQV has a tank size of 315L
Please speak to us about making the best choice for your needs and location.
5 - I don’t understand the use of a CO2 refrigerant by the Sanden "Eco®" Hot Water Heat Pump System. Isn’t CO2 a greenhouse gas and therefore harmful to the environment?
Yes, but CO2 has a Global Warming Potential of 1. Carbon dioxide is the baseline measurement of how it will contribute to global warming for a given mass.
Our system utilizes less than 1 kg of R744 (CO2) as a refrigerant contained in a closed system at the factory. The installer does not need to charge the heat pump on site.
6 - Why does Sanden "Eco®" Hot Water Heat Pump System use CO2 as a refrigerant?
- There is far less environmental impact (i.e. No ozone layer depletion and minimal global warming) than other commonly used refrigerants, should the system leak.
- There is a much higher efficiency, thereby allowing more heat to be transferred to the water, for less energy used (i.e. Excellent thermodynamic ability).
7 - What is the noise level of the Sanden "Eco®" Hot Water Heat Pump System?
The unit is rated at 38dB, which is almost silent. By comparison, a whisper is around 30dB and inside a library is approximately 40dB.
8 - What is the life expectancy of the Sanden "Eco®" Hot Water Heat Pump System?
The Sanden HWHP is designed to last for 15 years. The high quality, weather resistant construction of the "Eco®" Hot Water Heat Pump System outdoor module carries a warranty of 3 years, whereas the high quality, extra long life stainless steel storage tank carries a class leading 15 year warranty
9 - At what temperatures will the Sanden "Eco®" Hot Water Heat Pump System operate effectively?
The Sanden HWHP will operate effectively between minus 10 and plus 43 degrees C, without the need for an electric booster element. It is also fitted with in built freeze protection, making it suitable for all climates
10 - Does the Sanden Eco® Hot Water Heat Pump require the assistance of an electric booster element to heat water, when outside ambient temperatures are very low?
No, unlike other competitor HWHP systems, the Sanden Eco® HWHP system does not require an electric booster element
11 - Can I operate the Sanden "Eco®" Hot Water Heat Pump System on Off-Peak Tariffs?
Yes, please refer to the Installation Manual for details. There are no special settings for off peak connection. Simply ensure that the off peak tariff supplies a minimum of 5 hours continuous power to the Sanden HWHP.
12 - What are RECs and STCs and what are they worth?
The purchase and installation of a Sanden "Eco®" Hot Water Heat Pump System entitles you to Small-scale Technology Certificates (STCs) – formerly known as Renewable Energy Certificates (RECs). For more information: visit www.climatechange.gov.au and www.cleanenergyregulator.gov.au
We can give you or your installer advice on current rebates as these can change.
The Sanden HWHP achieves the highest level of STCs of any hot water heat pump, currently available in Australia, and these are as below:
Model |
Tank Size |
Zone 1 |
Zone 2 |
Zone 3 |
Zone 4 |
Zone 5 |
GAUS-160FQS |
160 Litre |
23 |
23 |
27 |
30 |
29 |
GAUS-250FQS |
250 Litre |
23 |
22 |
27 |
30 |
28 |
GAUS-300FQS |
300 Litre |
23 |
22 |
28 |
30 |
28 |
GAUS-315FQS |
315 Litre |
23 |
22 |
28 |
30 |
28 |
GAUS-315FQV |
315 Litre |
23 |
22 |
28 |
30 |
27 |
13 - Is water quality an important consideration for the Sanden "Eco®" Hot Water Heat Pump System?
Yes. Please refer to the Installation Manual for details. Importantly, no warranty applies to the heat pump unit and the storage tank, where the chloride level exceeds 200 mg/litre and the pH is less than 6.0. If in doubt, it is recommended that water chemistry information be sought from your local council or water supplier.
14. What do I do if the Sanden "Eco®" Hot Water Heat Pump System has a problem?
Firstly, review the Trouble Shooting Guide in the Installation Manual. If still unresolved, please Contact Us or the plumber you purchased your unit from. If you are unable to reach your Dealer/Installer, then please call Sanden on (02) 9791 0999
15 - If I go away from the house, can I turn the hot water heat pump off?
Yes you can. Turning off will not affect the unit. Just switch the power back on when you get back.
16 - Do I need to register my warranty?
Yes. For efficient processing of warranty claims, should they arise, please register your Sanden "Eco®" Hot Water Heat Pump System here.
17. What sizes are the Sanden "Eco®" Hot Water Heat Pump System available in?
The unit is available in four sizes as follows:
Yes. Please refer to the Installation Manual for details. Importantly, no warranty applies to the heat pump unit and the storage tank, where the chloride level exceeds 200 mg/litre and the pH is less than 6.0. If in doubt, it is recommended that water chemistry information be sought from your local council or water supplier.
14. What do I do if the Sanden "Eco®" Hot Water Heat Pump System has a problem?
Firstly, review the Trouble Shooting Guide in the Installation Manual. If still unresolved, please Contact Us or the plumber you purchased your unit from. If you are unable to reach your Dealer/Installer, then please call Sanden on (02) 9791 0999
15 - If I go away from the house, can I turn the hot water heat pump off?
Yes you can. Turning off will not affect the unit. Just switch the power back on when you get back.
16 - Do I need to register my warranty?
Yes. For efficient processing of warranty claims, should they arise, please register your Sanden "Eco®" Hot Water Heat Pump System here.
17. What sizes are the Sanden "Eco®" Hot Water Heat Pump System available in?
The unit is available in four sizes as follows:
Tank Size |
No of persons |
Typical dwelling |
Off peak / Continuous? |
STC Rebates available? |
160 Litre |
1-2 |
Unit / Town House |
Continuous only |
Yes |
250 Litre |
2 - 4 |
Residential |
Both |
Yes |
315 Litre (tall) |
3 - 6 |
Residential |
Both |
Yes |
315 Litre (short) |
3 - 6 |
Residential |
Both |
Yes |
Copyright© 2022 SANDEN International (Australia) Pty Ltd. All Rights Reserved. Reproduced with permission. E&OE. Please note: materials and specifications are subject to change without notice.
