Sanyo CO2 heat pump system installed at UK medieval priory

Having spent a day in Oban last week helping out moving Sanyo CO2 Eco air source heat pumps around, I thought it might be worth writing a short report on the job. But I've not got photographs yet, so that will have to wait for another day.

Instead, here's a report from that well known website R744.com about a Sanyo CO2 Eco air source heat pump installation down south.

A former priory on the UK coast, now serving as holiday accommodation, has been fitted with a state-of-the-art heating system encompassing Sanyo’s CO2 heat pumps, delivering high performance heating while ensuring low running costs.

Similar to Buckingham palace, the Woodspring Priory on the North Somerset coast is listed as a ‘Grade I’ building "of exceptional interest, sometimes considered to be internationally important" on the UK Statutory List of Buildings of Special Architectural or Historic Interest.

A heating system encompassing 3 Sanyo CO2 heat pumps

The old Liquefied Petroleum Gas (LPG) heating system was replaced by a state-of-the-art heating system encompassing three high efficiency SANYO ECO split system CO2 heat pumps.

At the heart of the CO2 ECO Heating System is SANYO’s innovative rotary two-stage compressor system, a world first in compressor design. The compressor is resistant to high working pressure differentials, has high reliability through load dispersion, low leakage and low vibration. It operates at a quiet 45 dB(A) noise level and, at only 9kg, the compressor is compact and lightweight.

SANYO’s CO2 heat pump can achieve temperatures of 65ºC, ideal for domestic hot water. Moreover, the system controls are intuitive and easy to operate, allowing users to set their preferred hot water temperature and create their ideal indoor environment. A 7-day week programme allows management of the space heating and hot water to match the lifestyle patterns and needs.

“The solution was chosen because the SANYO ECO technology has proven itself in a number of other Landmark projects. It is an excellent product, delivering high performance heating while ensuring low running costs”, said Martin Hook of South West Heat Pumps, the company responsible for the system installation.

Ecocute heat pumps have a number of advantages for use in Scotland namely

1. They are air source heat pumps that dump heat into a water tank that can then interface directly to a conventional wet raidiator heating system typical of most central heating systems. They can therefore act as a direct replacement for a gas or oil fired central heating boiler.
2. They use a natural refrigerant - carbon dioxide (CO2) which has a low Global Warming Potential (GWP). Heat pumps that use hydrofluorocarbon refrigerants (HFC, HCFC) suffer from the fact that a small fraction of the refrigerant included in the system leaks to the environment. The refrigerant R404a for example has a high GWP compared to CO2 - 3,500 times higher. There is a tendancy to merely consider the energy saving offered by heat pumps and disregard the greenhouse gas efffects from leakage of high GWP refrigerant. Unlike heat pumps working with natrual refrigrerants, like the Sanyo CO2 Eco air source heat pump, heat pumps working with high GWP refrigerant may not be as environmentally friendly as previously thought. And that includes most heat pump on the market in the UK today. [Thanks to Sanyo and Shecco in their response to the Renewable Heat Incentive (RHI) consultation for this insight].
3. They reduce CO2 emissions when compared to other forms of heating. The Scottish Government strategy is to decarbonise the electricity supply in Scotland and power everything (including heating and transport) using electricity by 2050. The target for renewable electricity generation in Scotland is 80% by 2020. As heat pumps are driven by electricity, their CO2 emissions reduce as the electricity supply is decarbonised.
4. They maintain heat pump performance down to -26 degrees centigrade. This is in direct contrast to air to water heat pumps that use HFC or HCFC refrigerants where the performance of the heat pump drops with temperature. As the temperature drops below 5 degrees centigrade, HFC or HCFC based air to water heat pumps act more and more like inefficient resitive heating.
5. They produce hot water at a higher temperature than air source heat pumps using HFC or HCFC refrigerants without using inefficient resistive electrical heating to boost temperatures. Typically the output temperature is 65 degrees centigrade, compatible with conventional radiator systems.
6. There is a local installer of the Sanyo CO2 Eco air source heat pump with first hand experience of these systems in different domestic installations.