Flooded Cooler Units - Carrier AquaForce 30XA Series Installation Instructions Manual

LEGEND
D — Drain, 3 / -in. NPT
4
D — Drain, / -in. NPT
1
4
E — Expansion Tank Connection,
FS — Flow Switch
PP — Pipe Plug,
PT — Pressure/Temperature Tap
T1 — Leaving Water Thermistor
T2 — Entering Water Thermistor
V — Vent,
1 / -in. NPT
4
*Field-supplied and installed.
†Factory-installed option.
**Required within 10 ft (3 m) of cooler in addition
to suction strainer for open loop systems.
a30-5297
Fig. 43 — Typical Piping Diagram on 30XA Units with Hydronic Package — Dual Pumps (Flooded Cooler)

FLOODED COOLER UNITS

NOTE: It is recommended for units with the hydronic package
that an inlet isolation (shut-off) valve be placed exterior to the unit
to allow removal and service of the entire pump assembly, if nec-
essary. The hydronic package is supplied from the factory with a
combination valve for isolation of leaving water. Also, if the unit
is isolated with valves, a properly sized pressure relief valve is rec-
ommended and should be installed in the piping between the unit
and the valves, following all applicable local codes.
Flooded Cooler Air Separation
For proper system operation, it is essential that water loops be in-
stalled with proper means to manage air in the system. Free air in
the system can cause noise, reduce terminal output, stop flow, or
even cause pump failure due to pump cavitation. For closed sys-
tems, equipment should be provided to eliminate all air from the
system.
The amount of air that water can hold in solution depends on the
pressure and temperature of the water/air mixture. Air is less solu-
ble at higher temperatures and at lower pressures. Therefore, sepa-
ration can best be done at the point of highest water temperature
and lowest pressure. Typically, this point would be on the suction
side of the pump as the water is returning from the system or ter-
minals. This is generally the optimal place to install an air separa-
tor, if possible.
1. Install automatic air vents at all high points in the system. (If
the 30XA unit is located at the high point of the system, a
INSIDE
UNIT
OUTSIDE
UNIT
3 / -in. NPT
4
1 / -in. NPT
4
V
HEATER
D
HYDRONIC PUMP PACKAGE
PT
PT
CHILLED
PT
WATER OUT
CHILLED
WATER IN
Pressure Relief*
Flexible Connections*
Pressure Reducing
Fill Valve*
vent can be installed on the piping leaving the heat exchanger
on the /
1
4
2. Install an air separator in the water loop, at the place where
the water is at higher temperatures and lower pressures —
usually in the chilled water return piping. On a primary-sec-
ondary system, the highest temperature water is normally in
the secondary loop, close to the decoupler. Preference should
be given to that point on the system (see Fig. 44). In-line or
centrifugal air separators are readily available in the field.
If it is not possible to install air separators at the place of the high-
est temperature and lowest pressure, preference should be given to
the points of highest temperature. It is important that the pipe be
sized correctly so that free air can be moved to the point of separa-
tion. Generally, a water velocity of at least 2 feet per second (0.6 m
per second) will keep free air entrained and prevent it from form-
ing air pockets.
Automatic vents should be installed at all physically elevated
points in the system so that air can be eliminated during system
operation. Provisions should also be made for manual venting
during the water loop fill.
Flooded Cooler Units with Hydronic Pump Package
The 30XA090-160 units can be equipped with a factory-installed
hydronic pump package consisting of a suction guide/strainer,
pump, combination valve, internal piping and wiring connected at
the factory.
120
D
D
PT
E PT
D
HEATER
Air Separator with Vent*
Strainer/Suction Guide
Reverse Flow Check
Valve/Service Valve
Service Valve
Pump
Combination Valve
Isolation Valve*
20 Mesh Stainer**
in. NPT female port.)
V
T1 PP
HEATER
FS PP T2
D