1. Presentation Heading Air Source Heat Pumps Jordan Jeewood
Heating Technical Executive

2. What is an Air Source Heat Pump?

3. What is an Air Source Heat Pump?
Refrigeration circuit used to heat water – fridge in reverse
Sealed refrigerant unit outputs hot water – outdoor unit
Plate heat exchanger transfers energy from hot refrigerant to water

4. What is an Air Source Heat Pump?
Produces hot water 25-58ºC – heating only
5kW, 8.5kW, 14kW Mitsubishi Electric Ecodan – domestic market
No need for refrigeration qualification to install
Approved Ecodan Installers – plumbers and heating engineers
-5ºC
58ºC

5. What is an Air Source Heat Pump?
R410A refrigerant
Very efficient way to heat water ~ %
For every 1 unit of energy put in, 3 useful units of energy out – high COP

6. Heat pump technology Inverter driven compressor and fan
Weather compensation
These technologies lead to greater efficiencies
Inverter control PCB
Inverter Compressor

7. Inverter Drive Technology
Duty (kW)
Heat load
Fixed speed
Inverter 10 5
Refrigerant 410A offers good efficiency
Inverter drive improves efficiency
Inverter drive improves control
Inverter drive reduces starting torque
Inverter drive reduces stress on the electrical supply
Inverter control system offers sophisticated diagnostics
Time

8. Weather Compensation
Heat load of property reduces as ambient temperature increases

9. Weather Compensation
Reducing flow temperature matches output of boiler to heat load

10. Weather Compensation
Heat pump has to draw less power to output lower flow temperatures
COP increases

11. Weather Compensation Covers first 2.5 weeks in Jan (very cold).
First week sub average outside temp sub zero.
Red and blue line – flow and return temps, demonstrates radiators are fine, space temp (red has been maintained even in these cool temps)
Green = COP, significant increase in COP as outdoor temp rises above zero.
Note average air temp in UK are 9.5. COPs of 3.5 should be easy to achieve in a well designed system.

12. UK Market Size – Domestic Heating
60 million people
26 million homes
1.6 million heating systems replaced / yr
85% gas boilers
4.5 million homes – off gas grid
4.7 million social housing

13. Why now? Cost effective Reliable and maintainable as existing systems
“Scalable” solution that can be easily “adapted” for the whole country
Future proof
Has to be absolutely acceptable to homeowners in terms of space, noise and usability

14. Cost effective
Payback period typically 5-10 years compared to oil, LPG, electricity
Payback period will decrease as:
Fossil fuels increase in price
The Technology becomes more commoditized
Manufacturing costs are decreased through economies of scale
Introduction of Renewable Heat Incentive (2012)

15. Reliability & Maintainability
Proven technology – air conditioning units used for years
Minimal servicing needed – like a fridge
Essentially a visual inspection, heat exchanger to be kept clean
Hot water to clean the coil and brush to remove debris e.g. leaves

16. Scalability
Potentially over 16 million homes are suitable – new build and retrofit
14kW
8.5kW
5kW
Since the 1970’s houses have increased the thermal efficiency quite dramatically.
The heat loads are not the same, the graph shows the percentage decrease.
2 Bed Flat Bed Semi Bed Detached

17. Scalability Geographically and seasonally independent
Manufactured in Scotland
National distribution network – already in place through aircon
Supporting Approved Ecodan Installers all over UK

18. Future proof Grid PV Hot Water Turbine Radiators mCHP Under floor
Heating

19. Acceptable to homeowners
No change in lifestyle or comfort level
Capable of providing both heating and hot water requirements for a property all year round – tank can be heated to 55ºC
Radiators and underfloor heating
Use of standard domestic heating controls
Quiet unit operation – typically 48dBA

20. Applying Air Source Heat Pumps

21. Applying Air Source Heat Pumps
Radiators or underfloor heating can be used
Heating and hot water separate – S Plan plumbing
Integrated like conventional boiler system
Supplies space heating via underfloor or rads
DHW cylinder supplying shower etc.
Heat pump positioned externally

22. Applying Air Source Heat Pumps
S Plan System
All fitting on cylinder package
Zone valves
Pump
Flow setter
Boiler buddy
Pump

23. Principals of Heat Pump Sizing
Heat Loss from Dwellings:
Fabric Heat Loss
Ventilation Heat Loss
Heat pump should be sized on peak heat loss of dwelling

24. Heat Loss of a Dwelling Victorian House Minimum boiler output = 10.8kW
1970’s House
Minimum boiler output = 6.6kW
2006 House
Minimum boiler output = 3.9kW
All 80m2 floor space, similar shape and -3oC outside, 22oC inside

25. Desired Room Temperature = 20oC Mean Water Flow Temperature = 40oC
Emitter Selection
Desired Room Temperature = 20oC
3 Points to consider:
Water flow temperature through emitter
Peak heat loss of room
Space to locate emitter
Mean Water Flow Temperature = 40oC

26. Applying Air Source Heat Pumps
Site survey is required for accurate heat loss calculation

27. Thank you
Discussion