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Operation
Unit operations should be controlled with
thermostat, or unit controller, never at the
main power supply, except for emergency,
servicing, or complete shutdown of the unit.
Thermostat Operation
Heating
Thermostat system switch - "Heat"
Thermostat fan switch - "Auto" or "On"
Thermostat temperature set to desired point.
Cooling
Thermostat system switch - "Cool"
Thermostat fan switch - "Auto" or "On"
Thermostat temperature set to desired point.
Air Circulation
Thermostat system switch - "Off"
Thermostat fan switch - "Auto" or "On"
No change of the thermostat temperature.
With these settings, the air handler’s supply
fan will run continuously but the supply air
will not be heated, cooled, or dehumidified.
System Off
Thermostat system switch - "Off"
Thermostat fan switch - "Auto"
No change of the thermostat temperature.
With these settings, the system is shut down,
with the exception of the control system
power (24 VAC), and the crankcase heaters
(about 60 watts/compressor).
Night and Weekend Unoccupied Operation
To reduce the operating time of the unit
when the space is unoccupied, such as nights
and weekends, it is recommended that the
temperature setting be raised about 5°F
while unoccupied during the cooling season
and lowered about 10°F during the heating
season.
Compressor
The compressors must be
off
for a minimum
of 5 minutes and
on
for a minimum of 5
minutes. Short cycling of the compressors
can causes undue stress and wear.
Variable Capacity Compressor
Controller
Units with variable capacity scroll
compressors may include variable capacity
compressor controller. The following is an
explanation of the terminals and
troubleshooting of the alert flash codes on
the controller. For more information on the
compressor controller, see Emerson Climate
Bulletin AE8-1328.
COMPRESSOR CYCLING
5 MINUTE MINIMUM OFF TIME
To
prevent
motor
overheating
compressors must cycle off for a
minimum of 5 minutes.
5 MINUTE MINIMUM ON TIME
To maintain the proper oil level
compressors must cycle on for a
minimum of 5 minutes.
The cycle rate must not exceed 6
starts per hour.
WARNING
Содержание CB-024
Страница 40: ...40 Refrigerant Piping Diagrams Figure 12 A C only piping AHU above CU ...
Страница 41: ...41 Figure 13 A C only piping AHU below CU ...
Страница 42: ...42 Figure 14 Modulating hot gas reheat piping AHU above CU ...
Страница 43: ...43 Figure 15 Modulating hot gas reheat piping AHU below CU ...
Страница 44: ...44 Figure 16 Hot gas bypass piping AHU above CU ...
Страница 45: ...45 Figure 17 Hot gas bypass piping AHU below CU ...
Страница 46: ...46 Figure 18 Modulating hot gas reheat with hot gas bypass piping AHU above CU ...
Страница 47: ...47 Figure 19 Modulating hot gas reheat with hot gas bypass piping AHU below CU ...
Страница 48: ...48 Figure 20 Heat pump piping AHU above CU ...
Страница 49: ...49 Figure 21 Heat pump piping AHU below CU ...
Страница 50: ...50 Figure 22 Heat pump with modulating hot gas reheat piping AHU above CU ...
Страница 51: ...51 Figure 23 Heat pump with modulating hot gas reheat AHU below CU ...