Preparation For Year-Round; Freeze Protection; Preparation For Winter Shutdown - Carrier AQUASNAP 30RB060-390 Installation Instructions Manual

PREPARATION FOR YEAR ROUND OPERATION If
the unit is in operation year-round, add sufficient suitable
inhibited antifieeze solution such as propylene or ethylene
glycol to chilled water to prevent tieezing under low-ambient
temperature operating conditions. Consult local water treat-
ment specialist on characteristics of water and recommended
inhibitoi:
IMPORTANT: Glycol anti-fieeze solutions are highly ]
recommended since heater tapes provide no protection
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in the event of a power failure.
If the unit is equipped with low ambient temperature head
pressure control, field-thbricated and field-installed wind bat-
tles are required if the wind velocity is anticipated to be reeater
than 5 mph (8 kan/h). Two different baffles are required, one for
the control box end and one for the opposite control box end.
Wind baffles should be constructed with minimum 18-gage
galvanized sheet metal or other suitable corrosion-resistance
material with cross breaks for strength. Use field-supplied
screws to attach baffles to the comer posts of the machine. Be
sure to hem or turn a tlange on all edges to eliminate sharp edg-
es on the baffles.
To avoid possibility of electrical shock, open all discon-
nects before installing or servicing this accessory.
To avoid damage to the retiigerant coils and electrical com-
ponents, use extreme care when drilling scaew holes and
screwing in fasteners.
Mount the smaller height baffle on the control box end. It is
recolrnnended that the upper notches be used tbr mounting the
baffles. This reduces the risk of dmnaging the coil while drill-
ing a mounting hole. Loosen the upper comer post bolts and
slide the baffle under the bolt and washer. Ti_lten the bolt.
Drill holes in the bottom of the tlange of the baffle and mount
with two screws to secure the bottom of the baffle to the comer
post. Repeat the process for the opposite side. See Fig. 47.
FREEZE PROTECTION The 30RB units are provided
with a flow switch to protect against fieezing situations that
occur tiom no water tlow. While the flow switch is helpful in
preventing tieezing during no-riow situations, it does not pro-
tect the chiller in case of power thilure during sub-tieezing
ambient temperatures, or in other cases where water tempera-
ture tails below the tieezing mark. Appropriate concentrations
of inhibited propylene or ethylene glycol or other suitable
inhibited antitieeze solution should be considered tbr chiller
protection where ambient temperatures are expected to tall
below 32 F (0 ° C). Consult local water treatment specialist on
characteristics of the system water and add a recolrnnended
inhibitor to the chilled water. The Carrier warranty does not
cover damage due to tieezing.
1. If the pump will be subjected to freezing temperatuxes,
steps must be taken to prevent fieeze damage. If the pump
will not be used during this thne, it is recolrnnended to
drain the pump and hydronic package and these compo-
nents are back-tlushed with inhibited glycol. Otherwise, a
glycol-water solution should be considered as the heat
transter tluid. INains axe located on the pump(s) and
suction mlide/strainer for units with hydronic kits. Units
without hydronic kits have a drain mounted on the bottom
of the heat exchanger near the leaving water connection of
the heat exchanger.
NOTE: Do not use automobile anti-fieeze, or any other tluid
that is not approved tbr heat exchanger duty. Only use appro-
priately inhibited glycols, concentrated to provide adequate
protection for the temperature considered.
2. Use an electric tape heater for the external piping, if unit
will be exposed to tieezing temperatures.
3. Ensure that power is available to the chiller at all times,
even during the off-season, so that the pump and cooler
heaters have power. Also make sure that the piping tape
heaters have power.
4. On units with pump packages, a heater is supplied with
the hydronic package that will protect this section tiom
tieezing in outdoor-air temperatures down to _0 F
(29 C), except in the case of a power thilure. The Carrier
warranty does not cover damage due to tieezing.
5. Cooler heaters that wilt protect components down to
_0 F (28.9 C) can be ordered as a factory-installed
option. Again, it should be noted that these heaters will
not protect the cooler ti'om tieezing in the event of a
power thilure. The Carrier warranty does not cover
damage due to tieezing.
PREPARATION FOR WINTER SHUTDOWN If the unit
!s not operational during the winter months, at the end of cool-
ing season:
Failure to remove power before draining heater equipped
coolers and hydronic packages can result in heater tape and
insulation damage.
1. If the unit has an optional heater on the cooler and the
cooler will not be drained, do not shut off power discon-
nect during off-season shutdown. It"the unit has an op-
tional heater on the cooler and the cooler will be drained,
open the circuit breaker for the heater, CB-HT or shut off"
power during off-season shutdown.
2. Draining the tluid tiom the system is highly recolrnnend-
ed. If the unit is equipped with a hydronic package, there
are additional drains in the pump housing and strainer
that must be opened to allow for all of the water to drain.
3. Replace the drain plug and add 2 gallons (7.6 liters) of a
suitable corrosion-inhibited anti-tieeze solution such as
propylene glycol to the cooler to prevent freezing of any
remaining water in system. Antitieeze can be added
through the vent on top of cooler. If the unit has a hydron-
ic pump package, the pump must also be treated in the
same manneE
4. Open one of the thermistor connections to allow air to
escape the vessel and the anti-tieeze to enter.
5. At the beginning of the next cooling season, be sure that
there is retiigerant pressure on each circuit before
refilling coolei; add recolmnended inhibitor, and reset the
CB-HT (circuit breaker heater) (if opened) or restore
power.
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