System information

19
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 energise, outdoor fan will turn off,
compressor will turn off for 30 seconds and then turn back on
to complete defrost. At the start of heating after conclusion of
defrost reversing valve will de-energise, compressor will turn
off for another 30 seconds, and the outdoor fan will stay off for
40 seconds, before starting in the heating mode.
Defrost
The defrost control is a time/temperature control (Fig. 21)
which includes a field-selectable time period (DIP switch 1 and
2 on the board) between defrost cycles of 30, 50 or 90 minutes
(factory set at 30 minutes). To initiate a forced defrost, two
options are available depending on the status of the defrost
thermostat.
If defrost thermostat is closed, speed-up pins (J1) must be
shorted by placing a flat head screw driver in between for 5
seconds and releasing, to observe a complete defrost cycle.
When the Quiet Shift switch is selected, compressor will be
turned off for two 30-second 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 speed-up pins are
shorted (with a flat head screw driver) for 5 seconds 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 second
compressor off period followed by 30 second of defrost with
compressor operation). On return to heating operation, com-
pressor will again turn off for an additional 30 seconds and the
outdoor fan for 40 seconds. When the Quiet Shift is in OFF
position, only a brief 30-second cycle will be observed.
If it is desirable to observe a complete defrost in warmer
weather, the defrost thermostat must be closed as follows.
1. Turn off power to outdoor unit and install lockout tag.
2. Disconnect outdoor fan motor lead from OF2 on control
board (Fig. 21). Tape to prevent grounding.
3. Restart unit in heating mode, allowing frost to accumulate
on outdoor coil.
4. After a few minutes in heating mode, liquid line tempera-
ture should drop below closing point of defrost thermostat
(approximately -1°C).
NOTE: Unit will remain in defrost until defrost thermostat
reopens at approximately 27 ° C coil temperature at liquid line
or remainder of defrost cycle time up to a maximum defrost
time of 10 minutes.
5. Turn off power tag disconnect to outdoor and reconnect
fan motor lead to OF2 on control board after above forced
defrost cycle.
MAINTENANCE
To ensure continuing high performance, and to minimise 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 Trouble-
shooting Chart at the end of these instructions.
NOTE TO EQUIPMENT OWNER: Consult your local dealer
about the availability of a maintenance contract.
WARNING: 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 User Manual.
FAILURE TO HEED THIS WARNING COULD RESULT
IN SERIOUS INJURY OR DEATH AND POSSIBLE
DAMAGE TO THIS EQUIPMENT.
WARNING: Failure to follow these warnings could result in
serious injury or death:
1. Turn off electrical power to the unit and install lockout
tag before performing any maintenance or service on
this unit.
2. Use extreme caution when removing panels and parts.
As with any mechanical equipment, personal injury can
result from sharp edges.
3. Never place anything combustible either on, or in
contact with, the unit.
CAUTION: Errors made when reconnecting wires may cause
improper and dangerous operation. Label all wires prior to
disconnecting when servicing.
The minimum maintenance requirements for this equipment
are as follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary.
2. Inspect indoor coil, drain, and condensate drain line each
cooling season for cleanliness. Clean when necessary.
3. Inspect fan motor and wheel for cleanliness each cooling
season. Clean when necessary.
4. Check electrical connections for tightness and controls for
proper operation each cooling season. Service when
necessary.
Air filter
IMPORTANT: Never operate the unit without a suitable air
filter in the return-air duct system. Always replace the filter
with the same dimensional size and type as originally
installed. See Table 1 for recommended filter sizes.
Inspect air filter(s) at least once each month and replace
(throwaway type) or clean (cleanable type) at least twice during
each cooling season and twice during the heating season, or
whenever the filter becomes clogged with dust and lint.