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Products  |  Thermal Engineering and HVAC  |  Refrigeration and Air Conditioning Technology  |  ET 900
ET 900 Introduction to Refrigeration Show data sheet (pdf file) Print page
Technical Description

  With simple and clear experiments this equipment is intended mainly as a basic introduction to refrigeration.
  ET 900 enables familiarisation with the operation and handling of a refrigeration system. The experimental unit includes all the necessary components for a fully operational refrigeration circuit, such as compressor, condenser, evaporator and a capillary tube as expansion element. Other components complement the scope of the equipment: display and control panel, pressure switches and pressure display to protect the compressor against excessive pressure and a flow meter and sight glass with filter/drier. Condenser and evaporator are each present twice: as air/refrigerant heat exchanger and as water/refrigerant heat exchanger. This allows for different component combinations.
  The components are mounted on plates and form installation-ready modules. 6 of the 8 modules are positioned in the frame at any one time and connected via hoses and supply cables. This allows for the construction of different simple compression refrigeration systems. For filling the system the refrigerant filling and evacuation equipment ET 150.01 is recommended.
  In experiments the processes in the equipment and the changes in the refrigerant state are initially demonstrated. Continued experiments allow the use of the equipment as a refrigeration system and as a heat pump. Pressures, flow rates and rated input of the compressor are displayed as important characteristic variables of refrigeration circuits. The temperature is measured by interlaboratory thermometers.

  The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.


Learning Objectives / Experiments

Fundamentals of a simple refrigeration circuit
- Detect and understand the cyclic process
- Changes of state of the refrigerant
- Represent the refrigeration circuit in the process

- Representation of the cyclic process in the

  log p-h diagram
- Estimate key figures, refrigeration capacity and heat

Different operating modes
- Cool air
- Generate cold water
- Heat pump (generate hot water)
Practical exercises
- Drain and fill refrigeration system (with ET 150.01)
- Fault finding

* Training system with interchangeable modules1
* Components mounted on plates1
* Rapid connection via hoses
Available accessories
ET 150.01 -- Refrigerant Filling and Evacuation Equipment
ET 150.02 -- Tool Set
Alternative products
ET 910 -- Refrigeration Training System, Base Unit
ET 900 Introduction to Refrigeration
[1] Set-up of simple refrigeration circuits with different components
[2] 8 self-contained operational modules mounted on a plate each
[3] Light-weight aluminium frame to arrange 6 modules
[4] Evaporator and condenser each available as air/refrigerant heat exchanger (finned tube heat exchanger) and as water/refrigerant heat exchanger (with pipe coil)
[5] Modules fitted with manual valves
[6] Components connected via hoses
[7] CFC-free refrigerant R134a
Technical Data
Hermetic refrigerant compressor
- power consumption: 67W at -10/32C
- refrigeration capacity: 151W at 5/32C
Tank content
- water tank, evaporator: 2L
- water tank, condenser: 3L
Pressure switch activation pressure
- LP: 1bar
- HP: 14bar
- intake pressure: 1...10bar
- delivery pressure: 1...30bar
Rotameter: 0.4...7.4L/h 
Dimensions and Weight
l x w x h: 1300x700x900mm
l x w: 370x340mm (component plates)
Weight: approx. 30kg
Required for Operation
230V, 50/60Hz, 1 phase or 120V, 60Hz/CSA, 1 phase
Scope of Delivery
1 frame
8 components on plates
1 set of hoses
1 set of cables
1 set of instructional material
Order Details

061.90000  ET 900  Introduction to Refrigeration

© 2005 G.U.N.T. Gerätebau GmbH