Product data

Application data (cont)
Vent and drain connections
All vents and drain connections are found in the waterbox
covers. Connection size is
3
⁄ 4 -in. FPT.
Provide high points of the chiller piping system with vents
and the low points with drains. If shut-off valves are pro-
vided in the main water pipes near the unit, a minimum
amount of system water is lost when the heat exchangers
are drained. This reduces the time required for drainage and
saves on the cost of re-treating the system water.
It is recommended that pressure gages be provided at
points of entering and leaving water to measure pressure
drop through the heat exchanger. Gages may be installed
as shown in Pressure Gage Location table shown below.
Pressure gages installed at the vent and drain connections
do not include nozzle pressure losses.
Use a reliable manometer to measure pressure differen-
tial when determining water flow. Regular gages are insen-
sitive and do not provide accurate measurement of flow
conditions.
PRESSURE GAGE LOCATION
NUMBER
OF PASSES
GAGE LOCATION
(Cooler or Condenser)
1, 3 One gage in each waterbox
2 Two gages in waterbox with nozzles
Range of application
The 23XL refrigeration machines are designed for standard
water chilling 60 Hz applications of 150 to 360 tons (530
to 1,270 kW) and 50 Hz applications of 130 to 300 tons
(460 to 1,060 kW) using refrigerant HCFC-22. The Frame
4 heat exchangers are available with HCFC-22 or
HFC-134a.
ASME stamping
All 23XL heat exchangers are constructed in accordance
with American Society of Heating, Refrigeration and Air
Conditioning Engineers (ASHRAE) 15 Safety Code for Me-
chanical Refrigeration (latest edition). This code, in turn,
requires conformance with American Society of Mechani-
cal Engineers (ASME) Code for Unfired Pressure Vessels
wherever applicable.
Relief-valve discharge pipe sizing
The 23XL is equipped with 3 relief valves (1 on the cooler
and 2 on the condenser). One additional relief valve (Frame
1 and 2 chillers) or 2 relief valves (Frame 4 chillers) are pro-
vided on the oil separator when an optional refrigerant iso-
lation package is used.
Relief-valve discharge piping sizing should be calculated
per the current version of the ASHRAE 15, latest edition,
code using the tabulated C factors for each vessel shown
below:
VESSEL
VESSEL
SIZE
RELIEF
VALVE SIZE
(in. FPT)
C FACTOR
(lb air/min) (kg air/s)
Cooler
10, 11
3
⁄ 4 46.6 0.35
20, 21
3
⁄ 4 46.6 0.35
40, 41 1 63.8 0.48
42, 43 1 63.8 0.48
Condenser
10, 11
3
⁄ 4 46.6 0.35
20, 21
3
⁄ 4 46.6 0.35
40, 41 1
1
⁄ 4 111.8 0.84
42, 43 1
1
⁄ 4 111.8 0.84
Oil
Separator*
10, 11
1
⁄ 2 Flare 20.3 0.15
20, 21
40, 41
3
⁄ 4 46.6 0.35
42, 43
3
⁄ 4 46.6 0.35
*Oil separator relief valve provided with optional refrigerant isolation
package.
NOTE: Frame 1 and 2 values are for HCFC-22 refrigerant. Frame 4 val-
ues are for both HCFC-22 and HFC-134a refrigerant.
Carrier further recommends that an oxygen sensor be
installedto protect personnel. Sensor should beableto sense
the depletion or displacement of oxygen in the machine
room below 19.5% volume oxygen per ASHRAE 15, lat-
est edition.
Design pressures
Design and test pressures for 23XL heat exchangers are
listed below.
DESIGN AND TEST PRESSURES
PRESSURES
SHELL SIDE TUBE SIDE
(Refrigerant) (Water)
psi kPa psi kPa
Design 300 2068 150 1034
Hydrostatic Test — — 225 1551
Air Test 375 2586 — —
HEAT EXCHANGER MATERIAL SPECIFICATIONS
ITEM MATERIAL SPECIFICATION
Shell HR Steel ASME SA516 GR .70
Tube Sheet HR Steel ASME SA516 GR .70
Waterbox* Cast Iron ASTM A-48 Class 35
Waterbox Cover† HR Steel ASME SA516 GR .70
Waterbox Shell† HR Steel ASME SA675 GR .60
Tubes Finned Copper ASME SB359
Discharge/Suction Steel ASME SA105/SA106
LEGEND
ASME — American Society of Mechanical Engineers
ASTM — American Society for Testing and Materials
HR — Hot Rolled
*Frame 1 and 2 machines.
†Frame 4 machines.
24