"If the question is 'Can Askews do it?' the answer is a very considered 'Yes'!"
Air Source Heat Pumps / Air to Water Heat Pumps
Why Askews Heat Pump?
Rapid progress in heating technology and improved building insulation allows water temperatures of 55ºC or less to be sufficient nowadays to heat a house thoroughly, even at extremely low outside temperatures. High levels of comfort with the added benefit of lower energy consumption can therefore be achieved due to the smaller temperature differential between the heat emitter and the room itself. Most modern water based heating systems operate at low temperatures, supplying heat via radiators or underfloor heating systems, individually or in combination.
Total solution for year round comfort
In addition to the basic comfort requirements of providing heat, the Askews system can deliver even more. The system is designed to supply your sanitary hot water needs all year round or can be selected to boost or pre-heat the water to 55ºC prior to your existing heating system, thus satisfying your desires for all year round comfort.
Selection of hot water cylinders for use with heat pump water heating systems
Optimised use of Heat Pump technology
Heat pumps are inherently clean and reliable, and traditionally use “water to water” or “air to air” technology. The Askews “air to water” system, however, represents the best of both technologies, combining:
- The accessibility of air as the heat source.
- Low investment cost: no high cost drilling or extensive excavation work is required nor the construction of a chimney. Consequently, the system is ideally suited for inner city applications or where space is limited.
- Emission free operation.
- Easy installation and maintenance, with the comfort of using a water based heating system.
Flexible application, easy installation
The Askews system features a compact outdoor unit which can be located discreetly outside new and existing residential/commercial properties.
| Question | What is a heat pump? |
| Answer | A heat pump extracts low temperature energy from the environment and increases its temperature for heating purposes. Heat pump efficiencies are normally quoted as the coefficient of performance of the system, these are typically in the range 3 to 5. In other words, extracting heat from renewable sources requires just 1kW of electrical input in order to generate 3kW to 5kW of heating output. Heat pump systems therefore, are 3 to 5 times more efficient than fossil fuel boilers and are more than capable of warming a |
How does an Air Source Heat Pump work ?
Heat pumps use the same basic principle as that employed in a refrigerator or freezer but in reverse. An air source heat pump works by extracting low-grade heat from the ambient air. The unit utilises a heat exchanger coupled with a fan. The refrigerator rejects heat from the contents to keep it cool, a heat pump uses this heat to heat water to provide for space heating or sanitary hot water.
Economical use of solar heat: Askews heat pumps
- Four functional units interact to raise the temperature of the heat extracted from the environment to a higher level: evaporator, condenser, expansion valve and compressor.
- Askews Heat pumps transfer the heat absorbed from the environment in an evaporator to a CFC-free working fluid.
- A compressor increases the pressure of the working fluid. The compression causes the temperature of the refrigerant to rise.
- The heat is transferred to the heating water in a heat exchanger.
- The expansion valve expands the refrigerant causing it to become cold again.
System Configuration
The Askews system can be configured in three ways in order to optimise the balance between investment and running costs, and to extend the types of projects for which our system can be used. Professional installers will provide details on how each of these versions can be applied to any particular building. In addition to these three configurations, Askews heat pumps can also be combined with alternative renewable heat sources such as solar panels.
Back up Heater system
The heat pump is sized to provide 90-95% of the annual heating requirement, with the remaining 5-10% supplied by a small electric back up heater. A good practice is to select the heat pump to cover 60% of the heating demand on the coldest day. Using the Askews system in the “Back up” configuration is recommended for the majority of applications because it offers the optimum balance between investment costs and running cost.
The Full Heat pump System
The heat pump is sized to provide 100% of the heating requirement on the coldest day of the year. This solution is recommended for ultra-low energy houses and for moderate climates without severe winters. The initial investment costs may be higher but energy consumption is the lowest of all systems.
The combined system
The Askews combined systems combine two separate heat sources, the heat pump and a fossil fuel boiler. There are two types of combined system: series connected (where the configuration is the same as a back up system but with the back up heater replaced by the boiler) and parallel connected. When series connected the boiler is sized to cover capacity peaks only, in parallel configuration the boiler is sized to cover the full capacity on the coldest day of the year. The parallel combined configuration is recommended where a heating system exists. Adding the Askews heat pump optimises the energy consumption of the system.
Systems available 3KW to 250KW (Call or email for detailed specifications)
For more information about our products and services please contact us direct using the information below:
tel: 01282 863825 fax: 01282 869602 email: sales@askewsltd.com