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

PREPARATION FOR YEAR ROUND OPERATION — If
the unit is in operation year-round, add sufficient suitable
inhibited antifreeze solution such as propylene or ethylene
glycol to chilled water and heat reclaim to prevent freezing
under low-ambient temperature operating conditions. Consult
local water treatment specialist on characteristics of water and
recommended inhibitor.
IMPORTANT: Glycol anti-freeze solutions are highly
recommended since heater tapes provide no protection
in the event of a power failure.
If the unit is equipped with low ambient temperature head
pressure control, field-fabricated and field-installed wind baf-
fles are required if the wind velocity is anticipated to be greater
than 5 mph (8 km/h). Two different baffles are required, one for
the control box end and one for the opposite end of the control
box. 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 corner posts of the
machine. Be sure to hem or turn a flange on all edges to elimi-
nate sharp edges on the baffles.
WARNING
Disconnect all power to the unit before performing mainte-
nance or service. Unit may automatically start if power is
not disconnected. Electrical shock and personal injury
could result.
CAUTION
To avoid damage to the refrigerant coils and electrical com-
ponents, use extreme care when drilling screw holes and
screwing in fasteners.
Mount the smaller height baffle on the end of the control
box. It is recommended that the upper notches be used for
mounting the baffles. This reduces the risk of damaging the
coil while drilling a mounting hole. Loosen the upper corner
post bolts and slide the baffle under the bolt and washer. Tight-
en the bolts. Drill holes in the bottom of the flange of the baffle
and mount with two screws to secure the bottom of the baffle to
the corner post. Repeat the process for the opposite side. See
Fig. 57.
FREEZE PROTECTION — The 30RB units are provided
with a flow switch for chilled water to protect against freezing
situations that occur from no water flow. For freeze protection
of the chiller in case of power failure during subfreezing ambi-
ent temperatures, or in other cases where water temperature
falls below the freezing mark, other methods must be used. Ap-
propriate concentrations of inhibited propylene or ethylene gly-
col or other suitable inhibited antifreeze solution should be
considered for chiller protection for both chilled water and heat
reclaim, where ambient temperatures are expected to fall below
32 F (0° C). Consult local water treatment specialist on charac-
teristics of the system water and add a recommended inhibitor
to the chilled water. The Carrier warranty does not cover dam-
age due to freezing.
60
(179.4kPa)
50
(149.5kPa)
40
(119.6kPa)
30
(89.7kPa)
20
(59.8kPa)
10
(29.8kPa)
0
0 100
6.3
Fig. 52 — 30RB060-130
Cooler Pressure Drop Curves
30RB150-190 and 30RB315A,B; 330A,B; 345A,B; 360A,B; 390A,B
60
(179.4kPa)
50
(149.5kPa)
40
(119.6kPa)
30
(89.7kPa)
20
(59.8kPa)
10
(29.8kPa)
0
0 200
0.0 12.6
Fig. 53 — 30RB150-190 and 30RB315A,B; 345A,B;
360A,B; 390A,B Cooler Pressure Drop Curve
70
(209.3kPa)
60
(179.4kPa)
50
(149.5kPa)
40
(119.6kPa)
30
(89.7kPa)
20
(59.8kPa)
10
(29.8kPa)
0
0
200
0.0
12.6
Fig. 54 — 30RB210-300
Cooler Pressure Drop Curve
54
30RB060-130
080, 090, 100
060, 070
110, 120, 130
200 300 400 500 600
GPM
12.6 18.9 25.2 31.5 37.8
L/s
400 600 800
GPM
25.2 37.8 50.5
L/s
30RB210-300
1200
400 600 800 1000
GPM
25.2
37.8 50.5 63.1
L/s
700
44.2
1000
63.1
1400
75.7 88.3