Description Of Each Control Operation - York DCPM Technical Manual

923180-UTG-A-1112
36K Indoor Heat Pumps
DESCRIPTION OF EACH CONTROL
OPERATION
Temperature & Current Parameters
• Indoor preset temperature (T
• Indoor ambient temperature (T
• Evaporator coil temperature (T
• Condenser coil temperature (T
• Defrost compensation temperature (T
• Outdoor ambient temperature (T
• Measured temperature of outdoor condensing coil under
cooling mode and measured temperature of indoor evapo-
rator coil under heating mode (T
• Indoor ambient temperature (T
Basic Functions
Once energized, the compressor should never be restarted
within less than 3 minutes. In a situation where memory func-
tion is available when energized for the first time, if the com-
pressor is at stop before de-energized, it will re-start without a
3-minute lag. If it has been in operation before de- energized,
the compressor will start with a 3-minute lag. Once started, the
compressor will not be stopped within 6 minutes regardless of
changes in room temperature.
Cooling Mode
1. Cooling Mode Operation
T
• When T , cooling mode is activated. The indoor
amb preset
fan, outdoor fan and the compressor will operate simulta-
neously. The indoor fan will run at preset speed.
T
• When T - 3.6,°F the compressor will stop, the
amb preset
outdoor fan will stop with a time lag of 60 seconds, and the
indoor fan will run at preset speed.
• When T - 3.6°F < T
preset
remain at its previous state.
In cooling mode, the four-way valve will be de-energized and
temperature can be set within a range from 61 to 86°F. If the
compressor stops running, the indoor fan and the swing device
will operate at original state.
28
)
preset
.)
amb
)
evap
)
outdoor pipe
)
compensation
)
outdoor amb
).
tube
indoor amb)
. < T + 1.8°F, the unit will
amb preset
T
amb.
T
preset
+3.6 ºF
T
preset
6 minutes 3 minutes
C o m p e r s sor
Outdoor fan
Indoor fan Preset fan speed
Run
2. Protection – Cooling Mode
• Antifreeze protection - In cooling and dehumidification
mode, antifreeze protection is activated 6 minutes after the
compressor has started if one of followings occur:
35.6 °F, the compressor will operate at reduced
 T
evap
frequency.
30.2 °F is detected for a duration of 3 minutes,
 T
evap
the compressor will stop and after 60 seconds, the out-
door fan will stop. In cooling mode, the indoor fan and the
swing motor will remain at the original state.
.  42.8 °F and the compressor has remained in
 T
evap
OFF mode for at least 3 minutes, the compressor will
resume its original operation state.
• Total current up and frequency down protection if the fol-
lowings occur:
 16A, the compressor frequency will start to
 I
total
increase
17A, the compressor frequency will not increase
 I
total
18A, the compressor will run at reduced frequency
 I
total
20A, the compressor will immediately stop and the
 I
total
outdoor fan will stop after 60 seconds
Start cooling
Original working state
Stop cooling
6 minutes
Stop
Johnson Controls Unitary Products