Carrier AQUASNAP 30RAP010-150, Installation Instructions Manual

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3. The pressure at all points in the system must be high
enough to prevent flashing in the piping or cavitation in
the pump.
The pressure created by an operating pump affects system
pressure at all points except one — the connection of the
compression tank to the system. This is the only location in the
system where pump operation will not give erroneous pressure
indications during the fill. Therefore, the best location to install
the fill connection is close to the expansion tank. An air vent
should be installed close by to help eliminate air that enters
during the fill procedure.
Ensure the following when filling the system:
1. Remove temporary bypass piping and cleaning/flushing
equipment.
2. Check to make sure all drain plugs are installed.
3. Open the blow-down valve to flush the strainer.
Normally, a closed system needs to be filled only once. The
actual filling process is generally a fairly simple procedure. All
air should be purged or vented from the system. Thorough
venting at the high points and circulation at room temperature
for several hours is recommended.
NOTE: Local codes concerning backflow devices and other
protection of the city water system should be consulted and
followed to prevent contamination of the public water
supply. This is especially important when antifreeze is used
in the system.
Set Water Flow Rate — Once the system is cleaned, pressur-
ized, and filled, the flow rate through the chiller must be estab-
lished. On units with the hydronic package, this can best be
done using the balancing valve.
In order to adjust the balancing valve, put a differential
pressure gage across the pressure taps on the valve. Make sure
that all system isolation and control valves are open. Use Ta-
bles 4-7 to determine gpm.
1. Measure the pressure drop across the balancing valve. If
the pressure reading is in psig, multiply psig by 2.31 to
convert to feet of water before using Tables 4-8.
2. Go to the row in the chart corresponding to the setting on
the valve, interpolating if necessary.
3. The gpm corresponding to the pressure drop measured is
the flow through the balancing valve.
NOTE: Carrier recommends a differential pressure gage when
measuring pressures across the pumps or balancing valves.
This provides for greater accuracy and reduces error build-up
that often occurs when subtracting pressures made by different
gages.
On primary/secondary systems, it is advisable to set the
30RAP balancing valve to maintain design flow plus 10%
through the chiller.
A rough estimate of water flow can also be obtained from
the pressure gages across the 30RAP heat exchanger.
Figures 24-31 show the relationship between gpm and heat ex-
changer pressure drop. It should be noted that these curves are
for “clean” heat exchangers; they do not apply to heat exchang-
ers with fouling. To read the chart, subtract the readings of the
two pressure gages on the hydronic kit. This number is the
pressure drop across the heat exchanger. Adjust the factory-in-
stalled balancing valve or external balancing valve (units with-
out hydronic package) until the correct pressure drop is ob-
tained for the required gpm. Total unit pressure drop is found in
Appendix A.
Water Treatment — Fill the fluid loop with water (or brine)
and a corrosion-resistant inhibitor suitable for the water of the
area. Consult the local water treatment specialist for character-
istics of system water and a recommended inhibitor for the
cooler fluid loop.
Untreated or improperly treated water may result in corro-
sion, scaling, erosion, or algae. The services of a qualified wa-
ter treatment specialist should be obtained to develop and mon-
itor a treatment program.
x
x
DILUTED
CLEANING
AGENT
S Y S TEM
POT FEEDER AND
TRAN
S FER PUMP
3 0RAP UNIT
TO DRAIN
TEMPORARY
PUMP
TEMPORARY
BYPA
SS
Fig. 22 — Typical Set Up for Cleaning Process
a30-5289
x
x
DILUTED
CLEANING
AGENT
S Y S TEM
S IDE
S TREAM
FILTER
POT FEEDER AND
TRAN
S FER PUMP
3 0RAP UNIT
TO DRAIN
TEMPORARY
PUMP
TEMPORARY
BYPA
SS
Fig. 23 — Cleaning Using a Side Stream Filter
a30-5290
CAUTION
Water must be within design flow limits, clean, and treated
to ensure proper chiller performance and reduce the poten-
tial of tube damage due to corrosion, scaling, erosion, and
algae. Carrier assumes no responsibility for chiller damage
resulting from untreated or improperly treated water.