Case studies

Project: Chilling the brewing water for Brauhaus Tegernsee

Main components:

Chilling of 190 hl brewing water from +16°C to +2°C in 2.5 hours / Implemented in 2010 / Witt liquid chilling unit with separator and evaporator in gravity circulation, together with an air-cooled condenser unit


Ammonia (NH3)/secondary refrigerant: glycol

System start-up:


Prior to the alterations, wort chilling (4 brews per day) was carried out with the classic ice bank method. The brewery's plans to increase output to 9 brews per day necessitated a new refrigeration solution. The task comprised planning a system operating at practically constant capacity all day long. In addition, it should include scope for possibly integrating a heat pump in the system at a later point in time to supply heat to the adjoining buildings ("Braustüberl", grammar school etc.).


Planning of an indirect refrigeration system capable of chilling 190 hl brewing water from +16°C to +2°C in 2.5 hours. In addition, the cooling water consumption for the condensers should be reduced or avoided.


An NH>3 system was installed with separator and plate evaporator as a gravity unit. The redundant concept also included two reciprocating compressors. To dispense completely with cooling water, an air-cooled condenser was chosen for refrigerant condensation.

This system cools a glycol circuit to -2°C. A secondary plate heat exchanger (glycol/brewing water) with outlet temperature control then brings the brewing water to the required temperature (+2°C) which is stored in an isolated tank.

Technical data:

Type of facility:

Indirect cooling system (ammonia/glycol)



Refrigerant volume:

100 kg

Secondary refrigerant:

Propylene glycol 32%

Evaporation temperature

-8 °C

Condensation temperature:


Refrigerating capacity:

124 kW

Main components:

Reciprocating compressor unit

Special features/Comments:

The system is prepared for subsequent integration of an NH3 heat pump


TH. WITT Kältemaschinenfabrik GmbH

Lukasstraße 32

52070 Aachen, Germany