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8
BELT DRIVE UNITS
The fan belt and variable pulleys are factory installed and set,
but may need to be adjusted for specific applications. Check
the fan to ensure its rotation is in the proper direction before
adjusting performance. To alter fan performance, adjust the
pulley settings to provide the applications full load design air
flow. Set the indoor fan pulley to the application design point
CFM for heating and cooling so that the CFM is not lower than
the minimum CFM allowed in the product data.
BELT DRIVE UNITS WITH A VFD
The fan belt and variable pulleys are factory installed and set,
but may need to be adjusted for specific applications. Check
the fan to ensure its rotation is in the proper direction before
adjusting performance. To alter fan performance, first adjust
the pulley settings to provide the applications full load design
air flow when running at the Supply Fan Maximum Speed
(
Configuration
UNIT
FS.MX
). The unit operating speeds
can then be adjusted with Fan Speed - Free Cool Lo (
Configu-
ration
I.FAN
FS.E1
), Fan Speed - Mech Cooling (
Config-
uration
I.FAN
FS.CL
), Fan Speed - Reheat 2 (
Configura-
tion
I.FAN
FS.RH
), and Fan Speed — Ventilation (
Con-
figuration
I.FAN
FS.VN
). Set the indoor fan pulley to the
application design point CFM for heating and cooling at 100%
fan speed so that the CFM is not lower than the minimum CFM
allowed in the product data. If the exact CFM cannot be set by
the half turn pulley settings then adjust the Supply Fan Maxi-
mum Speed (
FS.MX
) to fine tune the CFM to the application
requirements. The VFD’s settings should not be used for ad-
justing fan performance. Specific VFD information can be
found in Appendix C.
For belt drive units with a power exhaust option, the controls
require an accurate supply duct CFM at the unit design point
where the indoor fan will run at the Supply Fan Maximum
Speed (
FS.MX
) for proper operation. The supply duct CFM is
configured by the Indoor Fan Max Speed CFM (
Configura-
tion
ECON
IDF.C
). Default values for Indoor Fan Max
Speed CFM (
IDF.C
) are generally set per chassis and should
be changed. It is preferred to use the supply duct CFM from an
air balance report to configure the Indoor Fan Max Speed CFM
(
IDF.C
). If an air balance report is not available, then use the
fan tables to determine Fan Max Speed CFM (
IDF.C
). When
using the fan tables to determine Fan Max Speed CFM (
IDF.C
)
set Economizer Position Test (
Service Test
INDP
ECON
)
to 0 (Economizer Damper Closed) and Indoor Fan Speed Test
(
Service Test
FANS
F.SPD
) equal to Supply Fan Maxi-
mum Speed (
FS.MX
). Measure the supply to return duct static
pressure difference and indoor fan RPM. Make correction to
static pres sure for all options installed in the unit per the acces-
sory pressure drop table. Determine Indoor Fan Max Speed
CFM (
IDF.C
) on the fan table where the corrected static pres-
sure and RPM cross.
Condenser Fans and Motors
Condenser fans and motors are factory set.
Return-Air Filters
Check that correct filters are installed in filter tracks (see Phys-
ical Data table in Installation Instructions). Do not operate unit
without return-air filters.
Outdoor-Air Inlet Screens
Outdoor-air inlet screens must be in place before operating
unit.
Accessory Installation
Check to make sure that all accessories including space ther-
mostats and sensors have been installed and wired as required
by the instructions and unit wiring diagrams.
Orifice Change (48HC)
This unit is factory assembled for heating operation using natu-
ral gas at an elevation from sea level to 2000 ft.
Use accessory high altitude kit when installing this unit at an
elevation of 2000 to 7000 ft. For elevations above 7000 ft, refer
to High Altitude section to identify the correct orifice size for
the elevation. Purchase these orifices from your local Carrier
dealer. Follow instructions in accessory Installation Instruc-
tions to install the correct orifices.
Use accessory LP (liquid propane) gas conversion kit when
converting this unit for use with LP fuel usage for elevations
up to 7000 ft. For elevations above 7000 ft, refer to High Alti-
tude section to identify the correct orifice size for the elevation.
Purchase these orifices from your local Carrier dealer. Follow
instructions in accessory Installation Instructions to install the
correct orifices.
IMPORTANT: The Supply Fan Maximum Speed (
FS.MX
)
RPM must not produce a supply CFM that is lower than the
minimum CFM allowed in the product data for heating and
cooling.
Содержание /50HC 04-28
Страница 61: ...61 Fig 21 Saturated Condensing Temperature Thermistor Location 48 50HC 14 SCT B SCT A CIRCUIT B CIRCUIT A ...
Страница 69: ...69 Fig 24 Typical Control Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Страница 70: ...70 Fig 25 Typical Power Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Страница 71: ...71 Fig 26 Typical Control Diagram for 50HC 04 14 Units 50HC 14 shown ...
Страница 72: ...72 Fig 27 Typical Power Diagram for 50HC 04 14 Units 50HC 14 Non Humidi MiZer shown ...
Страница 73: ...73 Fig 28 Typical Control Diagram 48HC 17 28 Units ...
Страница 74: ...74 Fig 29 Typical Control Diagram 50HC 17 28 Units ...
Страница 75: ...75 Fig 30 Typical Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Страница 76: ...76 Fig 31 Typical Non Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Страница 89: ...89 Fig 42 Modulating ERV Wiring Schematic ...
Страница 90: ...90 Fig 43 EnergyX ERV Control Box Component Layouts ...
Страница 101: ...101 Fig 59 Exhaust Fan Assembly Removal Exhaust Fan Assembly ...
Страница 141: ......