Air-water heat pumps

We support the industry in its efforts to develop energy-efficient refrigeration systems and heat pumps.

The ILK Dresden has been active in the development and testing of refrigeration and heat pump technology for many years. The development work is carried out individually and in close cooperation with the client. The experiences of the ILK Dresden were and are continuously collected in a multiplicity of research projects.

In recent years, for example, the development of a high-temperature heat pump with operation temperatures above 120 °C has been an important research project.

Within the limits of our flexible accreditation, further measurement tasks can be carried out in accordance with applicable testing standards. Outside accreditation, further services can be offered:

• Performance testing of WP with storage tanks
• dynamic power measurements by means of temperature and power profile
• Investigations of the cooling circuit of the heat pump
• Expert opinions and evaluations of individual components
• Characterisation of the operating behaviour of the heat pump
• Refrigerant and material testing
• Modifications of the systems by qualified refrigeration technicians on site in consultation with the customer

For measurements on (pre-) series devices as well as prototypes an additional air volume flow measurement is possible. A qualified measuring section with a max. air volume flow of approx. 5000 m³/h is available for this purpose. This results in extended evaluation possibilities for the current standard, which can be used for device optimization.

• Source side balancing possible
• Variation air volume
• Simulation of real outdoor installation conditions

The measurements of the heat pumps are carried out in accordance with currently valid guidelines (ErP) and standards DIN EN 14511 or DIN EN 14825. If required, minor deviations are possible due to our flexible accreditation (see below Annexes to accreditation, p. 3)

A multi-zone climate chamber is available for the tests. Measurements of small refrigeration capacities can be also carried out using the calorimeter method with environmental compensation in this climate chamber. The testing of the heating capacity is normally based on the water-enthalpy method. For this, the water mass flow and the temperatures are measured directly at the inlet and outlet of the heat pump. The test points are based on the current guidelines and test standards of certification bodies, quality labels (EHPA guidelines) and current standards.

Heat pumps with fixed-speed compressors and power-controlled heat pumps can be tested. Outside the accreditation of the Testzentrum PLWP, dynamic tests under changing conditions depending on the heat load are also possible. For this purpose, appropriate temperature and heat load profiles can be specified.

The performance data of the test rig are given in the following tables.

Heat source air

A multi-zone climate chamber is available to simulate the air side. Depending on the installation conditions, the heat pump is installed inside or outside the climate chamber. Split heat pumps are installed inside and outside the climate chamber.

¹⁾ max. humidification 10 kg/h

Heat sink water

A water circuit is used as a heat sink, which is adjusted to the test conditions via a mixing station and provides tempered water at the heat pump inlet. The water content of the water circuit used is sufficiently large to prevent thermal feedback.

Electrical power measurement

The electrical power consumption is measured with a precision power analyzer. The mains voltage in the test field is specially stabilised for power measurement.