Johnson Controls SABROE DualPAC, Руководство по эксплуатации

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Operating manual – DualPAC with reciprocating compressors
0012201 en 2021.04
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Design and function
Fig. 18: Oil recovery pot
When the oil level in the recovery pot, Fig. 18, is high, the float switch is activated. The switch
turns on the solenoid valve in the oil recovery system. Incoming discharge gas pushes down the
piston, pos. 3, which blocks the oil drain inlet port. Discharge gas is led into the oil reservoir
through the small nozzle, pos. 2. The rising pressure forces the oil back into the suction side of
the compressor.
To ensure proper functioning, a timer delays the off-signal from the float switch for a few seconds.
Note: As shown in Fig. 18, the float ball must be positioned with NO facing upwards.
For further information about the oil recovery pot, see chapter 8. Appendices .
3.2.10 Automatic oil return from oil separator
The oil collected in the oil separator is returned to the compressor by a timer-operated solenoid
valve. The timer can be adjusted in the UniSAB III controller.
3.2.11 By-pass function during start-up
The R717 charge on DualPAC is very low. The DualPAC is therefore equipped with a by-pass from
the bottom of the oil separator to the GHUR intermediate cooler. R717 condensed in the oil sepa-
rator during standstill is led to the GHUR cooler through a timer-operated solenoid valve, which is
open during standstill and for a short start-up period only. The timer can be adjusted in the Uni-
SAB III controller.
3.2.12 WHC circulation system
The SABROE WHC circulation system is designed to maintain optimum cooling water temperature
on heat pumps and refrigeration compressors with water-cooled top and side covers. The system
ensures a constant cooling water temperature thus giving the compressor optimum operating
conditions. The system circulates water (or glycol) during both operation and standstill.
DN2
5
1
NO
NC
2
3
Oil
Oil / R-717
Discharge gas