SECTION 4 – INSTALLATION
FORM QWC3-NM1
ISSUE DATE:11/20/2020
QUANTECH
39
4
Control Transformer Primary Voltage
Tappings
It is important to check that the correct primary tapping
has been used on the control transformer:
• With the supply to the unit isolated remove the lid
to the transformer box.
• Check that the tapping used conforms to the site
supply voltage. The two tappings are 342-424V
and 360-440V.
COMPRESSOR HEATERS
Compressor heaters are standard. If power is OFF
more than two hours, the crankcase heaters must be
energized for 18 to 24 hours prior to restarting a com-
pressor. This will assured that liquid slugging and oil
dilution does not damage the compressors on start.
RELIEF VALVES
Relief valves are located on both the high and low pres-
sure side of the piping. High side relief valve pressure
setting is 560 PSIG.
HIGH PRESSURE CUTOUT
On 60 Hz chillers, a high pressure cutout is installed in
the discharge piping of each system. The cutout opens
at 500 PSI plus or minus 8 PSIG and automatically
closes at 375 PSIG plus or minus 10 PSIG.
On 50Hz chillers, all models will utilize a manual re-
set high pressure cutout of 503 PSIG (34.7 barg). On
chillers with compressors exceeding a swept volume
of 25L/sec, a second tool reset cutout is installed with
a cutout of 532 PSIG (36.7 barg). These cutouts con-
form to relevant requirements of Pressure Equipment
Directive PD 97/23/EC.