8
Fig. 14 — Tightening Locking Collar
STAGED AIR VOLUME CONTROL — 2 SPEED
FAN WITH VARIABLE FREQUENCY DRIVE
(VFD)
Staged Air Volume (SAV™) Indoor Fan Speed
System
The Staged Air Volume (SAV) system utilizes a Fan Speed
control board and Variable Frequency Drive (VFD) to automat-
ically adjust the indoor fan motor speed in sequence with the
unit’s ventilation, cooling and heating operation. Per ASHRAE
(American Society of Heating, Refrigerating, and Air-Condi-
tioning Engineers) 90.1-2016 standard section 6.4.3.10.b,
during the first stage of cooling operation the SAV system will
adjust the fan motor to provide two-thirds (
2
/
3
) of the design
airflow rate for the unit. When the call for the second stage of
cooling is required, the SAV system will allow the design air-
flow rate for the unit established (100%). During the heating
mode, the SAV system will allow total design airflow rate
(100%) operation. During ventilation mode, the SAV system
will operate the fan motor at
2
/
3
speed.
Identifying Factory Option
This supplement only applies to units that meet the criteria de-
tailed in Table 3. If the unit does not meet that criteria, discard
this document.
Table 3 — Model-Size / VFD Option Indicator
See Appendix A for an example of model number nomenclature.
Unit Installation with SAV Option
50HC ROOFTOP
Refer to the base unit installation instructions for standard re-
quired operating and service clearances.
See “Variable Frequency Drive (VFD) Installation, Setup and
Troubleshooting Supplement” for wiring schematics, perfor-
mance charts, and configuration.
See Fig. 15-17 for locations of the variable frequency drive
(VFD) as mounted on the various 50HC models.
Fig. 15 — VFD Location for Sizes 07-09
Fig. 16 — VFD Location for Size 12
Fig. 17 — VFD Location for Size 14
ADDITIONAL VARIABLE FREQUENCY DRIVE
(VFD) INSTALLATION
AND TROUBLESHOOTING
Additional installation, wiring, and troubleshooting informa-
tion for the Variable Frequency Drive can be found in the fol-
lowing manual: “Variable Frequency Drive (VFD) Installation,
Setup and Troubleshooting Supplement.”
MODEL / SIZES
POSITION IN
MODEL NUMBER
VFD FIOP
INDICATOR
50HC / 07-28
17
G, J
IMPORTANT: The remote VFD keypad is a field-installed
option. It is not included as part of the factory-installed VFD
option.
T --- 25 TORX SOCKET
HEAD CAP SCREW
LOCKING COLLAR
VARIABLE
FREQUENCY
DRIVE (VFD)
VARIABLE
FREQUENCY
DRIVE (VFD)
VARIABLE
FREQUENCY
DRIVE (VFD)
Summary of Contents for WeatherMaster 50HC04
Page 32: ...32 Fig 63 RTU Open Overlay for Economizer Wiring ...
Page 33: ...33 Fig 64 VFD Overlay for W2770 Controller Wiring ...
Page 86: ...86 Fig C 50HC A07 PAC Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 91: ...91 Fig H 50HC D12 PAC Control Diagram 208 230 3 60 460 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 93: ...93 Fig J 50HC A04 A06 PAC Power Diagram 208 230 1 60 APPENDIX D WIRING DIAGRAMS ...
Page 95: ...95 Fig L 50HC A07 PAC Power Diagram 208 230 3 60 460 3 60 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 100: ...100 Fig Q 50HC D11 PAC Power Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 101: ...101 Fig R 50HC D11 PAC Power Diagram 460 3 60 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 103: ...103 Fig T 50HC D14 PAC Power Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 104: ...104 Fig U 50HC D14 PAC Power Diagram 460 3 60 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 124: ...124 Fig AO PremierLink System A04 A06 Wiring Diagram APPENDIX D WIRING DIAGRAMS ...
Page 125: ...125 Fig AP RTU Open System Control A04 A06 Wiring Diagram APPENDIX D WIRING DIAGRAMS ...
Page 126: ...126 Fig AQ PremierLink System A07 D14 Wiring Diagram APPENDIX D WIRING DIAGRAMS ...
Page 127: ...127 Fig AR RTU Open A07 D14 Wiring Diagram APPENDIX D WIRING DIAGRAMS ...