Carrier AQUAZONE 50PSH, Инструкция по установке, запуску и обслуживанию

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This connection must be in conformance with local plumbing
codes. A trap must be installed in the condensate line to ensure
free condensate flow. (Heat Pumps are not internally trapped). A
vertical air vent is sometimes required to avoid air pockets. See
Fig. 8. The length of the trap depends on the amount of positive
or negative pressure on the drain pan. A second trap must not be
included.
Fig. 8 — Condensate Trapping
The horizontal unit should be pitched approximately 1⁄4 in.
towards the drain in both directions, to facilitate condensate
removal. See Fig. 9.
Fig. 9 — Sloped Horizontal Unit Installation
Step 7 — Pipe Connections
Depending on the application, there are 3 types of WSHP piping
systems to choose from: water loop, ground-water and ground
loop. Refer to Piping Section of Carrier System Design Manual
for additional information.
All WSHP units use low temperature soldered female pipe thread
fittings for water connections to prevent annealing and out-of-
round leak problems which are typically associated with high tem -
perature brazed connections. Refer to Table 1 for connection sizes.
When making piping connections, consider the following:
• Use a backup wrench when making screw connections to
unit to prevent internal damage to piping.
• Insulation may be required on piping to avoid condensa -
tion in the case where fluid in loop piping operates at tem -
peratures below dew point of adjacent air.
• Piping systems that contain steel pipes or fittings may be
subject to galvanic corrosion. Dielectric fittings may be
used to isolate the steel parts of the system to avoid gal -
vanic corrosion.
WATER LOOP APPLICATIONS
Water loop applications usually include a number of units
plumbed to a common piping system. Maintenance to any of these
units can introduce air into the piping system. Therefore, air elimi -
nation equipment comprises a major portion of the mechanical
room plumbing.
The flow rate is usually set between 2.25 and 3.5 gpm per ton of
cooling capacity. For proper maintenance and servicing, pressure-
temperature (P/T) ports are necessary for temperature and flow
verification.
Cooling tower/boiler systems typically utilize a common loop
maintained at 50 to 100°F. The use of a closed circuit evapora -
tive cooling tower with a secondary heat exchange between the
tower and the water loop is recommended. If an open type cool -
ing tower is used continuously, chemical treatment and filtering
will be necessary.
In addition to complying with any applicable codes, consider the
following for system piping:
• Piping systems using water temperatures below 50°F re -
quire 1⁄2-in. closed cell insulation on all piping surfaces to
eliminate condensation.
• Avoid all plastic to metal threaded fittings due to the po -
tential to leak. Use a flange fitted substitute.
• Teflon tape thread sealant is recommended to minimize in -
ternal fouling of the heat exchanger.
• Use backup wrench. Do not overtighten connections.
• Route piping to avoid service access areas to unit.
• Flush the piping system prior to operation to remove dirt
and foreign materials from the system.
GROUND-WATER APPLICATIONS
Typical ground-water piping is shown in Fig. 10. In addition to
complying with any applicable codes, consider the following for
system piping:
• Install shut-off valves for servicing.
• Install pressure-temperature plugs to measure flow and
temperature.
• Connect boiler drains and other valves using a “T” connec -
tor to allow acid flushing for the heat exchanger.
• Do not overtighten connections.
• Route piping to avoid service access areas to unit.
• Use PVC SCH80 or copper piping material.
NOTE: PVC SCH40 should
not
be used due to system high pres -
sure and temperature extremes.
Water Supply and Quantity
Check water supply. Water supply should be plentiful and of good
quality. See Table 2 for water quality guidelines.
In all applications, the quality of the water circulated through the
heat exchanger must be within the ranges listed in the Water Qual -
ity Guidelines. Consult a local water firm, independent testing fa -
cility, or local water authority for specific recommendations to
maintain water quality within the published limits.
Condensate Drain
Connection
Vent (Optional)
Slope Down
Min. 1/8"
Per Foot
Trap Down
2" Min.
Elev
ation Line
When Mounted Level
1/4"
IMPORTANT: Failure to comply with the above required water
quality and quantity limitations and the closed-system
application design requirements may cause damage to the tube-
in-tube heat exchanger. This damage is not the responsibility of
the manufacturer.