Heatcraft Refrigeration Products BEACON II H-IM-79E, Installation And Operation Manual

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17
Defrost Delay Start Time
Example: The system is first powered up at 8:00 AM and
is programmed for 4 defrost per day. The user would like
the first defrost at 10:00 AM. To accomplish this, use the
“PROGRAM REVIEW”
button to scroll to
dFS
. Use the
“SELECTOR” switch to select 2 hours delay start, then
press
“ENTER.”
The 1
st
defrost will now occur at 10:00
AM and then a defrost will occur every 6 hours thereafter.
Time Remaining Until Next Defrost
(On Version 1.8 Boards)
To find out how much time is left until the next defrost is
scheduled, use the
“MONITOR”
button to scroll to
dFS
.
The time displayed will be how much time until the next
scheduled defrost.
Defrost Schedule In Memory
Beacon II does not have a real time clock but it keeps
track of the time that has elapsed in its memory. It also
keeps in memory the number of defrosts scheduled
and how much time has elapsed between defrosts. If a
power failure occurs, when power is restored Beacon
II remembers how many defrosts are scheduled and
it remembers how much time was left until the next
defrost. It will then defrost based on this timing. So, if the
power failure lasted 15 minutes, the defrost schedule will
be off by 15 minutes.
Resetting Defrost Schedule
When a power interruption causes a severe lag in the
defrost schedule, the defrost schedule can be reset in
the following manner. First, press the reset time button
on the board to zero out the internal counters. Then,
program the appropriate defrost delay start time for the
next desired defrost period. The defrost schedule will be
correct until you have another power outage.
Pumpdown / Defrost
Service Mode
A single pole, single throw switch (SPST) is supplied in
each condensing unit for shutting off the system. Closing
the “
SERVICE
” switch in the condensing unit will cause
the system to pumpdown and shut off. “
Ser
” will be
displayed on the Beacon board LED and “
SERVIC
”
is displayed on the Smart Controller LCD display. The
evaporator fan and heaters will be de-energized in the
Service Mode.
The system will not restart until the SPST switch is
placed in the “NORMAL” or “OFF” position.
OR
A remote “
SERVICE
” switch can be added to the
Beacon II board across the “
Ser
” and “
C
” connections of
the terminal block. It will operate in the same manner as
the switch above.
OR
The system can be pumped down by pressing the
“SERVICE”
button twice. To restart the system, press
the
“CLEAR”
button.
OR
The system can be pumpdown for service by closing
the liquid line service valve in the condensing unit, then
closing the suction line service valve when the system
trips on the low pressure switch.
In order for air defrost evaporator fan motors to cycle off
during “
SERVICE
” mode, the fan motors must be wired
through the fan relay on the Beacon II board.
Defrost
Defrost Timing
When power is first applied to the system, its timer
starts counting time. If 4 defrost are programmed, it will
initiate a defrost every 6 hours from when power was
first applied. Beacon II does not have a real time clock.
Beacon II does provide the ability to delay the starting of
the first defrost.