Table of Contents
Advertisement
A properly baffled storage tank is available from the factory as an
accessory for sizes 010-060 only. These tanks are designed to
physically fit beneath the corresponding 30RC unit, taking up the
same footprint.
•
30RC010, 015
•
30RC030
•
30RC035-060
Storage tank weight (water weight included) is as follows:
•
30RC010, 015
1673 lb (759 kg)
•
30RC030
2193 lb (995 kg)
•
30RC035-060
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 ex-
ceed the maximum loop volume limits (see Table 17). The limits
are dependent on the maximum and minimum temperatures of the
water, the maximum and minimum pressures seen by the expan-
sion tank, and the heat transfer fluid. Expansion tank and maxi-
mum loop volume data is as follows:
30RC010-030
Volume gal. (L)
5.0 (18.9)
Acceptance Volume gal. (L) 2.9 (11.0)
Table 17 — Maximum Loop Volume
30RC010-030
CONCENTRATION
GAL.
PURE WATER
230
10% EG
132
20% EG
123
30% EG
114
40% EG
107
10% PG
124
20% PG
106
30% PG
93
40% PG
83
LEGEND
EG —
Ethlyene Glycol
PG —
Propylene Glycol
NOTE:
1. Maximum loop volume is based on typical system of 12 psig (83 kPa) and
30 psig (207 kPa) of min/max pressures, and 38°F (3.3°C) and 100°F
(37.8°C) min/max water temperature.
2. If the volume in the system is greater than the limits listed, then extra expan-
sion tank volume must be added to the system.
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 in-
creased flow. If greater flow is necessary, look at opening the bal-
ance valve. Also, verify that the strainer is clean, and that no un-
necessary system resistance is present, such as partially closed iso-
lation 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 provided in the
30RC hydronic kit are easily removable for this purpose. Refer
to the pump literature packet supplied with the hydronic package
information on Seal Replacement in the Service Section, and fol-
low its instructions for impeller removal. Trimming should only
be done by a qualified machine shop that has experience in this
operation. Contact your local Carrier representative for a
83 gallons (314 liters)
119 gallons (450 liters)
241 gallons (912 liters)
30RC035-060
10.0 (37.9)
5.5 (20.8)
30RC035-060
L
GAL.
871
738
500
425
466
394
431
366
405
342
469
399
401
339
352
298
314
267
recommended machine shop. After trimming, the impeller
MUST be balanced. Failure to balance trimmed impellers can
result in excessive vibration, noise, and premature bearing fail-
ure. Impeller trimming has the added benefit of maximum bhp
savings.
PREPARATION FOR YEAR-ROUND OPERATION
If the unit is in operation year-round, add sufficient suitable inhib-
ited antifreeze solution such as propylene or ethylene glycol to
chilled water to prevent freezing under low-ambient temperature
operating conditions. Consult a local water treatment specialist on
characteristics of water and recommended inhibitor.
IMPORTANT: Glycol antifreeze solutions are highly rec-
ommended since heater tapes provide no protection in the
event of a power failure.
High efficiency variable condenser fans are required if ambient
temperatures are below 45°F (7°C) on size 020-030 units, and
32°F (0°C) on size 035-060 units.
Accessory wind baffles are required with high-efficiency variable
condenser fans if the wind velocity is anticipated to be greater than
5 mph (8 km/h). Unit sizes 010-030 require one baffle and unit
sizes 035-060 require two baffles. See Table 18.
Table 18 — Wind Baffle Accessory Quantities
ACCESSORY
PART NO.
30RA-900---
L
2793
064
1609
065
1491
066
1385
1294
1510
1283
To avoid damage to refrigerant coils and electronic
1128
components, use extreme care when drilling screw holes and
1011
attaching fasteners.
FREEZE PROTECTION
The 30RC units are provided with a water strainer and a flow
switch to protect against freezing situations that occur from no wa-
ter flow. While the flow switch (thermal dispersion) is helpful in
preventing freezing during no-flow situations, it does not protect
the chiller in case of power failure, or in other cases where water
temperature falls below the freezing mark. Appropriate concentra-
tions of inhibited glycol or other suitable inhibited antifreeze solu-
tion should be considered for chiller protection where ambient
temperatures are expected to fall below 32°F (0.0°C). Consult lo-
cal water treatment specialist on characteristics of the system wa-
ter and add a recommended inhibitor to the chilled water.
Do not circulate water through unit without strainer in place.
Failure to use the strainer represents abuse and may impair or
otherwise negatively affect the Carrier product warranty.
1.
If the pump will be subjected to freezing temperatures, steps
must be taken to prevent freeze damage. If the pump will not
be used during this time, it is recommended to drain the pump
and hydronic package and back-flush these components with
inhibited glycol. Otherwise, a glycol-water solution should be
considered as the heat transfer fluid. Units have a drain
mounted on the piping leaving the heat exchanger. Drains are
located on the sheet metal base of all units.
NOTE: Do not use automobile antifreeze, or any other fluid
that is not approved for heat exchanger duty. Use only
35
UNIT SIZE 30RC
010,
025,
035,
020
015
030
040
1
—
—
—
—
1
—
2
—
—
1
—
CAUTION
CAUTION
045-060
—
—
2
Advertisement
Table of Contents
