International comfort products PHN524, Руководство по установке

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17
FIGURE 15
Typical Heat Pump Operation -- Heating Mode
COMPRESSOR
ACCUMULA
TO
R
OUTDOOR COIL
INDOOR COIL
LCS
LEGEND
HPS – High Pressure Switch
LCS – Loss of Charge Switch
Accurater
®
Metering Device
Arrow indicates direction of flow
Bypass
Position
Metering
Position
HPS
Metering Device
Step 3 — Defrost Control
Quiet Shift
Quiet Shift is a field--selectable defrost mode, which will
eliminate occasional noise that could be heard at the start
of defrost cycle and restarting of heating cycle. It is
selected by placing DIP switch 3 (on defrost board) in ON
position.
When Quiet Shift switch is placed in ON position, and a
defrost is initiated, the following sequence of operation
will occur. Reversing valve will energize, outdoor fan will
turn off, compressor will turn off for 30 sec and then turn
back on to complete defrost. At the start of heating after
conclusion of defrost reversing valve will de--energize,
compressor will turn off for another 30 sec, and the
outdoor fan will stay off for 40 sec, before starting in the
Heating mode.
Defrost
The defrost control is a time/temperature control which
includes a field--selectable time period (DIP switch 1 and
2 on the board) between defrost cycles of 30, 60, 90, or
120 minutes. Factory settings are show below. To initiate
a forced defrost, two options are available depending on
the status of the defrost thermostat.
Factory--Set Defrost Times
2 Ton 3 Ton 4 Ton 5 Ton
120 min 90 min 60 min 90 min
If defrost thermostat is closed, speed--up pins (J1) must
be shorted by placing a flat head screw driver in between
for 5 sec and releasing, to observe a complete defrost
cycle. When the Quiet Shift switch is selected,
compressor will be turned off for two 30 sec intervals
during this complete defrost cycle, as explained
previously. When Quiet Shift switch is in factory default
OFF position, a normal and complete defrost cycle will be
observed.
If defrost thermostat is in open position, and speedup
pins are shorted (with a flat head screw driver) for 5 sec
and released, a short defrost cycle will be observed
(actual length is dependent upon the selected Quiet Shift
position). When Quiet Shift switch is in ON position, the
length of defrost is 1 minute (30 sec compressor off
period followed by 30 sec of defrost with compressor
operation). On return to heating operation, compressor
will again turn off for an additional 30 sec and the outdoor
fan for 40 sec. When the Quiet Shift is in OFF position,
only a brief 30 sec. cycle will be observed.
NOTE :Unit will remain in defrost until defrost thermostat
reopens at approximately 65
_
F (18
_
C) coil temperature
at liquid line or remainder of defrost cycle time.
MAINTENANCE
To ensure continuing high performance, and to minimize
the possibility of premature equipment failure, periodic
maintenance must be performed on this equipment. This
heat pump unit should be inspected at least once each
year by a qualified service person. To troubleshoot unit,
refer to Table 8.
NOTE :TO EQUIPMENT OWNER: Consult your local
dealer about the availability of a maintenance contract.
PERSONAL INJURY AND UNIT DAMAGE HAZARD
Failure to follow this warning could result in personal injury
or death and unit component damage.
The ability to properly perform maintenance on this
equipment requires certain expertise, mechanical skills,
tools and equipment. If you do not possess these, do not
attempt to perform any maintenance on this equipment,
other than those procedures recommended in the Owner’s
Manual.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow these warnings could result in personal
injury or death:
1.
Turn off electrical power to the unit and install a
lockout tag before performing any maintenance or
service on this unit.
2.
Use extreme caution when removing panels and
parts.
3.
Never place anything combustible either on or in
contact with the unit.
!
WARNING