Presentation Heading Air Source Heat Pumps Jordan Jeewood Heating Technical Executive

What is an Air Source Heat Pump?

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

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 Air @ -5ºC Water @ 58ºC

What is an Air Source Heat Pump? R410A refrigerant Very efficient way to heat water ~ 300-400% For every 1 unit of energy put in, 3 useful units of energy out – high COP

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

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

Weather Compensation Heat load of property reduces as ambient temperature increases

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

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

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.

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

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

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)

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

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 3 Bed Semi 4 Bed Detached

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

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

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

Applying Air Source Heat Pumps

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

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

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

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

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

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

Thank you Discussion