York YLPA 0115SE, Инструкция по установке, эксплуатации и обслуживанию

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33
JOHNSON CONTROLS
FORM 150.68-ICOM1
ISSUE DATE: 10/15/2020
Suction pressure limiting in the cooling
mode will not unload a system. Suction
pressure limiting only prevents further
loading.
In the heating mode if the suction pressure falls below
the system actual suction pressure cut-out value then the
lag compressor will stop. On units with 3 compressors
per system, if after 20 seconds the suction pressure
does not rise above the systems actual suction pressure
cut-out value, the next lag compressor will stop. The
system will be allowed to re-load after a delay of 180
seconds and after the suction pressure rises above the
suction limit point.
During defrost suction limiting, both loading
and unloading are disabled.
Models with 3 compressors in a system (Heat Pump
Mode Only)
SYS X MAX LOAD LIMIT
In the heating mode this message indicates that the
leaving hot liquid temperature is low and the number
of compressors allowed to run is restricted to prevent
low suction pressure trips.
If the Leaving Temperature is below 77°F the maximum
number of compressors allowed to run in a system is 2.
As the Leaving Temperature rises 9°F above the limit
temperature the system is be allowed to load.
SYS X LOAD LIMIT XX%
Load limiting is in effect at the percentage shown.
This limiting could be due to a load limit/PWM
input terminals 13 and 20 on -XTBC1 or a remote
communications device sending a load limit command.
MANUAL
OVERRIDE
MANUAL OVERRIDE mode is selected under the
OPTIONS key. In this mode the Daily Schedule
is ignored and the unit will start-up when liquid
temperature allows, and when the flow switch/remote
contacts, unit switch and system switches permit. This
is a priority message and cannot be overridden by other
STATUS messages.
MANUAL OVERRIDE should only be used
in emergencies or for servicing. MANUAL
OVERRIDE mode automatically disables
itself after 30 minutes.
Fault Status Messages
Safeties are divided into two categories - system safeties
and unit safeties. System safeties are faults that cause
the individual system to be shut down. Unit safeties
are faults that cause all running compressors to be shut
down.
System Safeties (Auto Reset)
SYS X DSCH INHIBIT
In the heat pump mode the discharge inhibit protects a
system from operating at low discharge pressure. After
a time override of 20 minutes from system start or the
end of a defrost the discharge pressure must be above
15 bar. If the discharge pressure is below 15 bar, the
system will stop with the above message and be held off
for 30 minutes. This condition will give an alarm and
be recorded in the history.
System Safeties (Three Faults - Lockout)
System safeties are faults that cause individual systems
to be shut down if a safety threshold is exceeded
for 3 seconds. The system will be allowed to restart
automatically after the fault condition is no longer
present. However, if 3 faults on the same system occur
within 90 minutes, that system will be locked out on
the last fault. This condition will require a manual reset
using the system switch (under OPTIONS key). The
switch must be turned off and then back on to clear the
lockout fault.
SYS X HIGH DSCH PRES
The software discharge pressure cut-out is backed-up by
a mechanical high pressure cut-out switch located in
each refrigerant circuit. The software cut-out assures that
the system pressure does not exceed safe working limits.
The system will shutdown when the programmable cut-
out is exceeded and will be allowed to restart when the
discharge pressure falls below the cut-out.
SYS X LOW SUCT PRESS