Heat recovery

The energy released during the cooling process is supplied to the water by the Lister-heat recovery system via a heat exchanger. If the water temperature of about 55-60 ° C is reached, a pressure switch will switch the cooling system to normal operation. It is guaranteed that the cooling system continues to operate under normal conditions.

The amount of hot water and the heat recovery basically depend on the quantity of milk. From 100 liters of milk to be cooled from about 35 ° C. to 4 ° C. about 70 liters of water can be heated from about 12 ° C  to 55 ° C. The heated water can be used to clean the milking machine, the milk cooling tank, to heat the milk for calves, as well as for kitchen and bathroom.

If desired, the heat recovery system can be fitted with an additional heating of 2kW / 230V or 4kW / 400V. This additional heating is used to bridge periods of low milk or reheat the existing hot water from about 55-60 ° C up to 80 ° C.

Type: WRG separate design C

WEG separate design C Boiler capacity
100 560 1040
150 660 1040
200 660 1280
300 660 1800
400 800 1500
500 800 1800
Larger boilers on request


  • The WRG, design separately "C" is intended for retrofitting of existing cooling systems.
  • Inner boiler for all models of stainless steel (1.4571)
  • Outer panelling:
    "C" = Plastic case
  • The WRG is operated without a sacrificial anode. Nevertheless no corrosion occurs in the boilers. This means no maintenance required for a long life.
  • Internal copper-fin tube-heat exchanger
  • Temperature display

Type: WRG with external plate heat exchanger

for compact and separate storage

Compact solutions extend the scope of use.

WRG with external plate heat exchanger TypePower, cooling unit
LPT 10 1.7 - 2.7
LPT 20 3.5 - 4.5
LPT 30 6.3 - 8.0
LPT 40 9.0 - 12.0
LPT 50 14.0


  • After a short running time of the cooling unit (approx 8 min.) hot water of about 55 ° C is already available
  • The water in the boiler is stacked from top to bottom, without any mixing of hot and cold water. The discharged water always has a constant temperature.
  • Also for retrofitting of milk cooling systems and WRG's of all makes.


  • Compact brazed plate heat exchanger made of profiled
  • stainless steel panels
  • (1.4401 W)
  • refrigerant pressure actuated, water regulating valve
  • water circulation pump
  • shut-off device
  • exhaust valve

Back to the milk cooling plants