| There isn't much else. The only critical thing is
the NYUMC chill water supplies to our water chiller. While the water
chiller pumps chilled water to R-AXIS, itself needs to be chilled
because its compressor will otherwise get burned. This is why the
chiller is connected to the NYUMC chill water system, of which the
piping configuration is shown in the figure. Check
the house chill water pressure meters frequently. Normal readings
from these meters are:
Meter A (in-water before regulator): around 160 psi.
Meter B (in-water after regulator): between 135 and 145 psi.
Meter C (return water): at least 20 psi below that of meter B.
However, very often Meter A would show readings above
180, even 200, psi, which makes the regulator malfuntioned and thus
Meter B shows readings almost the same as that of Meter C. When
this happens (much more often in the Summer), the chiller will keep
turning on-and-off* every few seconds and the return water becomes
very hot (you can actually feel it by grabbing the return water
pipe). Sometimes this will result in a temperature increase of the
circulating water (separate from the house water) to R-AXIS because
the chiller's compressor is not working normally. There is not much
you can do about it except to call NYUMC house maintenance department
IMMEDIATELY and ask them to lower the in-water pressure. If they
don't respond, keep calling until they do; otherwise, be prepared
for a complete R-AXIS shut down and even flooding in the lab because
the pressure may already be too high for the chiller's hoses to
take.
You should also change the water filter shown in the
drawing as frequently as possible (normally once every couple of
months). When you do so, don't forget to close the valves (not shown
in the picture) on the pipe. Ask MYUNMC maintenance department for
fitlters (two AP110 filters each time).
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*When the in- and out-water pressure difference is less than 20
psi, the chiller says "no water to cool me" and always
shuts down the compressor whenever it's turned on. On the other
hand, the water to chill R-AXIS from the chiller will go up with
its temperature. As soon as the temperature is above the preset
value, i.g. 60oF, the chiller wakes up the compressor to "drag"
down the temperature. These two instructions clash with each other
and that's why the chiller keeps turning on-and-off.
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