Carrier AQUASNAP 30RAP010-150, Руководство по установке

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Minimum Loop Volume — The minimum volume of fluid re-
quired to be in circulation is a function of the number of com-
pressors in the chiller as well as the type of application. The
minimum fluid in circulation must equal or exceed the values
in Table 9.
To achieve this fluid volume, it is often necessary to install a
tank in the loop. The tank should be baffled to ensure there is
no stratification and that water (or brine) entering the tank is
adequately mixed with liquid in the tank. See Fig. 32.
Table 9 — Minimum Fluid Volume In Circulation
LEGEND
The piping between the chiller and the accessory tank can
be done to allow the tank to be on the return side of the chiller
(tank piped to chiller inlet) or the supply side of the chiller
(tank piped to the chiller outlet). For standard compressors, it is
recommended that the tank be piped to the return side of the
chiller to buffer any changes in load to allow more stable chill-
er operation. For digital compressor applications, it is recom-
mended that the tank be piped to the supply side of the chiller
to provide a more stable supply temperature.
A properly baffled storage tank is available from the factory
as an accessory for sizes 010-060 only. These tanks are de-
signed to physically fit beneath the corresponding 30RAP unit,
taking up the same footprint.
• 30RAP010-018
83 gallons (314 liters)
• 30RAP030 119 gallons (450 liters)
• 30RAP035-060 241 gallons (912 liters)
Storage tank weight (water weight included) is as follows:
• 30RAP010-018 1673 lb (759 kg)
• 30RAP030 2193 lb (995 kg)
• 30RAP035-060 4361 lb (1978 kg)
Maximum Loop Volume (Units with Hydronic Package) —
Since the minimum size of the expansion tank is dependent
upon loop volume, units with the integrated hydronic kit must
not exceed the maximum loop volume limits below (see
Table 10). The limits are dependent on the maximum and
minimum temperatures of the water, the maximum and
minimum pressures seen by the expansion tank, and the heat
transfer fluid. Expansion tank and maximum loop volume data
is as follows:
30RAP010-030 30RAP035-060
Volume gal (L) 5.0 (18.9) 10.0 (37.9)
Acceptance Volume gal (L) 2.9 (11.0) 5.5 (20.8)
Pump Modification/Trimming (Units with Factory-Installed
Hydronic Package) — Since the pumps are constant speed,
the only way to obtain greater flow with a given pump/impeller
is to decrease system head. This will allow the pump to “ride”
its curve to the right, resulting in increased flow. If greater flow
is necessary, look at opening the balance valve. Also, verify
that the strainer is clean, and that no unnecessary system resis-
tance is present, such as partially closed isolation valves.
Increasing system resistance by closing the balancing valve
will force the pump to “ride” its curve to the left, resulting in
less flow. Although this does reduce power consumption
slightly, it may not be the desirable method of reducing the
flow, especially if a rather large reduction is needed.
The other method for reducing flow on a constant speed
pump is impeller trimming. The impellers in the pumps provid-
ed in the 30RAP hydronic kit are easily removable for this pur-
pose. Refer to the pump literature packet supplied with the
hydronic package information on Seal Replacement in the
Service Section, and follow its instructions for impeller remov-
al. Trimming should only be done by a qualified machine shop
that has experience in this operation. Contact your local Carrier
representative for a recommended machine shop. After trim-
ming, the impeller MUST be balanced. Failure to balance
trimmed impellers can result in excessive vibration, noise, and
premature bearing failure.
Impeller trimming has the added benefit of maximum bhp
savings. It is very possible for power savings to pay for the
trimming cost very quickly. The 30RAP pump option may be
applied with a field-supplied VFD. When applied with a VFD,
the maximum length of wiring between the drive and the pump
motor is 50 ft (15.2 m). The maximum allowable carrier fre-
quency of the inverter is 12 kHz, with 3 kHz recommended.
Table 10 — Maximum Loop Volume Limits
LEGEND
NOTE: Max loop volume is b ased on typical system of 12 psig
( 8 3 kPa) and 30 psig (207 kPa) of min/max pressures, and 100 F
(37. 8 C) mean temperature. If the volume in the system is greater
than the limits listed, then extra expansion tank volume must b e
added to the system.
30RAP
UNIT
SIZE
NORMAL AIR
CONDITIONING
APPLICATION
gal/ton (L per kW)
PROCESS COOLING OR
LOW AMBIENT
OPERATION APPLICATION
gal/ton (L per kW)
Std Unit HGBP Digital Std Unit HGBP Digital
010,015 12 (13.0) N/A 3 (3.3) 12 (13.0) N/A 6 (6.5)
018-030 6 (6.5) 4 (4.3) 3 (3.3) 10 (10. 8 ) 10 (10. 8 ) 6 (6.5)
035-150 3 (3.3) 3 (3.3) 3 (3.3) 6 (6.5) 6 (6.5) 6 (6.5)
HGBP — Hot Gas Bypass
BAD
BAD
GOOD
GOOD
Fig. 32 — Tank Baffling
CONCENTRATION
30RAP010-030 30RAP035-060
GAL. L GAL. L
PURE WATER 412 1560 1356 5131
10% EG 239 906 795 3009
20% EG 233 88 0 767 2902
30% EG 206 7 8 1 692 2620
40% EG 200 755 655 247 8
10% PG 233 88 0 767 2902
20% PG 200 755 655 247 8
30% PG 170 645 561 2124
40% PG 157 595 514 1947
EG — Ethlyene Glycol
PG — Propylene Glycol