1. Thermosyphon - Free Cooling
Smardt Chiller
with Thermosyphon

2. Definition
Free Cooling = chilled water production without compressor by low ambient temperature
Smardt-OPK Thermosyphon free cooling
Oil free turbo compressor + flooded
evaporator + air-cooled condenser +
Smardt-OPK know-how
Smardt Chiller Group | 2013 | Philipp Ampferl
Page 2

3. Compressor mode Condenser Com-pres-sor Expansion valve Evaporator
Refrigerant liquid
Refrigerant gas
Expansion valve
expansionvalve
Coolant outlet
Coolant inlet
Evaporator
Evaporator
Smardt Chiller Group | 2013 | Philipp Ampferl
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4. Thermosyphon - free cooling mode
Thermosyphon free cooling = chilled water without compressor - one
refrigerant circuit  „either or“ function
Condenser
Free- cooling valve
Com-pressor
Refrigerant liquid
Refrigerant gas
Coolant outlet
Coolant inlet
Evaporator
Smardt Chiller Group | 2013 | Philipp Ampferl
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5. Compressor vs Thermosyphon mode
Compressor mode
Thermosyphon free cooling mode
Condenser
Condenser
Condenser
Free- cooling valve
Expansion valve
Com-pressor
Com-pressor
Refrigerant liquid
Refrigerant gas
Refrigerant liquid
Refrigerant gas
Coolant outlet
Coolant inlet
Coolant outlet
Coolant inlet
Evaporator
Evaporator
Evaporator
Smardt Chiller Group | 2013 | Philipp Ampferl
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6. Compressor operation Two refrigerant circuits  „and“ function
Compressor mode
Compressor mode
Condenser
Condenser
Exp. valve
Compressor
Exp. valve
Refrigerant liquid
Refrigerant gas
Refrigerant liquid
Refrigerant gas ON
AUS ON
Evaporator
Coolant inlet
Coolant outlet
Smardt Chiller Group | 2013 | Philipp Ampferl
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7. Parallel operation Thermosyphon Compressor mode ON OFF Condenser
Freecooling valve
Exp. valve
Compressor
Refriger. liquid
Refrigerant gas
Refrigerant liquid
Refrigerant gas
AUS ON
OFF
Evaporator
Coolant inlet
Coolant outlet
Smardt Chiller Group | 2013 | Philipp Ampferl
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8. Thermosyphon free cooling
Condenser
Condenser
Free- cooling valve
Compressor
Free-cooling valve
AUS
OFF
OFF
Evaporator
Coolant inlet
Coolant outlet
Smardt Chiller Group | 2013 | Philipp Ampferl
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9. Thermosyphon free cooling
Condenser
Condenser
Free- cooling valve
Compressor
OFF
AUS
OFF
Evaporator
Coolant inlet
Coolant outlet
Smardt Chiller Group | 2013 | Philipp Ampferl
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10. Advantages of Thermosyphon
Lower investment
No separate dry cooler system
No additional water pipes and pumps needed
Smaller footprint
Reduced power consumption/
Environment-friendly
No loss of efficiency by heat transfer (heat exchanger glycol/water)
No additional free cooling pumps
Lower sound pressure
Smardt Chiller Group | 2013 | Philipp Ampferl
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11. Ambient air temperature of Stuttgart according to DIN 4710
Example Stuttgart
Ambient air temperature of Stuttgart according to DIN 4710
Hours per year
Ambient air temperature
Smardt Chiller Group | 2013 | Philipp Ampferl
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12. Example Stuttgart Percentage Thermosyphon free cooling mode Load
Compressor mode
Thermosyphon mode
Load
Chilled water outlet temp.
For a ∆T of 10°C between Evaporator outlet temp. and ambient temp.
Smardt Chiller Group | 2013 | Philipp Ampferl
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13. Energy consumption compressor
Energy consumption without Thermosyphon
Energy consumption with Thermosyphon
compressor work p. a/ cooling work p.a.
Evaporator outlet temperature
Smardt Chiller Group | 2013 | Philipp Ampferl
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14. Thermosyphon models Air-cooled Smardt-Chiller Split Smardt-Chiller
Smardt Chiller Group | 2013 | Philipp Ampferl
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15. Thank you for your attention!
Smardt Chiller Group | 2013 | Philipp Ampferl
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