Option / option designation Function
Defroster / bc
Moisten components of the control and regulating system with anti‐
freeze.
Tab. 65 Low temperature equipment options
4.6.4.1 Option bb
Pre-heat the drive engine coolant
The drive engine coolant can be pre-heated in order to attain an improved cold-start behaviour. An
electric pre-heating device has been installed for this purpose. The heating element of the pre-
heating device protrudes directly into the drive engine coolant.
The thermal output from the heating element into the coolant results in a slower circulation of the
coolant. Resulting from the circulation the supplied heat is evenly distributed. The coolant of the
drive engine and its direct surrounding significantly warm up above the local ambient temperature.
A melting protection protects against overheating.
The ideal pre-heating time depends on the outside temperature. Approx. 3 hours of pre-heating
time result in thermal balance. This means that subsequently supplied heat only serves to maintain
the already existing temperature. The rest of the subsequently supplied heat is emitted to the sur‐
roundings.
Damages to the drive engine and electrical pre-heating device are precluded with pre-heating
times lasting longer than 3 hours. However, the unnecessary energy consumption should be
prevented by shutting down the pre-heating device on time!
A flexible power cable has been included with the machine. To commission the pre-heating device
you only need to connect the power cable to the machine’s connection and the user's power sock‐
et.
Further information See Fig. 10 for the position of the device connection.
4.6.4.2 Option bb
Device connection of coolant pre-heating on the machine
Fig. 10 Device connection on the machine
1
Machine
2
Device connection
3
Drive engine
4
Heating element
5
Pre-heating device
4
Design and Function
4.6
Options
No.: 9_9548 22 HCE
Operating Manual Portable Rotary Screw Compressor
MOBILAIR M27 PE
49
Option bb