Bohn MAC4X Installation Manual

MAC Series

Condensing Units

H-IM-67G December, 2003 Part #25006401

Replaces H-IM-67F (12/03)

Installation and Operation Manual

TABLE of CONTENTS

General safety and inspection

Condensing unit specifications................................ 2

Evaporator unit specifications ................................. 3

Evaporator placement ............................................. 4

Refrigerant piping and line sizes .......................... 6-8

Leak detection and evacuation ............................... 9

Field wiring ............................................................ 10

Beacon II Controller

Installation ...........................................................11

Refrigerant line brazing

™

Power supply

Wiring ................................................................. 12

Box temp control settings
Refrigerant charging

Start-up operation .............................................. 13

Initial power on

Operating mode display ..................................... 14

Program & review settings/changes .................. 15-19

Low ambient operation

Pumpdown .................................................... 19-20

Defrost................................................................ 20

Alarms and error indicator LED.......................... 21

Evaporator fans shut down by operators
Power failure
Service mode
Space sensor terminal

Checking sensors............................................... 22

System defaults

Control sensor and piping .................................. 23

Checking operation of exp. valve

Exp. valve motor winding resistance.................. 24

Smart Controller ............................................ 25-36

Operational checkout ......................................... 37

Preventive maintenance................................ 38-40

Diagnostics....................................................... 41-44

Beacon II parts lists.......................................... 45-46

Startup Checklist ..............................................47-48

Wiring diagrams ............................................... 49-51

Warranty information............................................. 52

General Safety Information

General Safety Information

1. Installation and maintenance to be performed only by certified personnel who are familiar with this type of
equipment.

2. Make sure that all field wiring conforms to the requirements of the equipment and all applicable national
and local codes.

3. Avoid contact with sharp edges and coil surfaces. They are a potential injury hazard.

4. Make sure all power sources are disconnected before any service work is done on units.

WARNING: Refrigerant can be harmful if it is inhaled. Refrigerant must be used and recovered

responsibly. Failure to follow this warning may result in personal injury or death.

Inspection

Responsibility should be assigned to a dependable individual at the job site to receive material. Each
shipment should be carefully checked against the bill of lading. The shipping receipt should not be signed
until all items listed on the bill of lading have been accounted for. Check carefully for concealed damage. Any
shortage or damages should be reported to the delivering carrier. Damaged material becomes the delivering
carrier’s responsibility and should not be returned to the manufacturer unless prior approval is given to do so.
When uncrating, care should be taken to prevent damage. Heavy equipment should be left on its shipping
base until it has been moved to the final location.

Condensing Unit Specifications

Figure 1.

Table 1. Condensing Unit Specifications

Model Location Compressor Voltage HP Unit Unit Unit 90% full

MCA MOP kW lbs.

MAC3X
MAC4X
MAC5X

MAC7X
MAC8X

MCA = Minimum Circuit Ampacity MOP = Maximum Overcurrent Protection
Note: Remote circuits internal volume = .10 cu. ft. Approximate unit weight = 825 lbs.

Freezer ZF09K4E 208-230/3/60 1 1/2 9.0

Cooler RS64C1E 208-230/1/60

Freezer ZF13K4E 208-230/3/60 3 9.0

Cooler RS43C1E 208-230/1/60

Freezer ZF15K4E 208-230/3/60 3 1/2 14.0

Cooler RS43C1E 208-230/1/60

Freezer ZF13K4E 208-230/3/60 3 9.0

Cooler CS10K6E 208-230/1/60 1 1/2 9.0

Freezer ZF15K4E 208-230/3/60 3 1/2 14.0

Cooler CS10K6E 208-230/1/60 1 1/2 9.0

3

/4 9.0

1

/2 9.0

1

/2 9.0

26.9 35.0 4.3

28.8 40.0 6.3

36.2 50.0 6.4

33.8 45.0 6.4

41.0 50.0 6.5

2

Receiver

Evaporator Unit Specifications

Table 2. Evaporator Unit Specifications

Evaporator Model Location Cap. No. of Dimensions (in.) Connections (In.) Amps Weight

BTUH Fans A B Suct. ID Liq. OD Mtrs. Htrs. (lbs.)

MAC3X

MAC7X

MAC8X

MAC4X

MAC5X

Figure 2.

ADT070BHB2N6MK Cooler 7,000 2 45.50 33.25

LET090BHB2N6MK Freezer 9,000 2 45.50 33.25

ADT104BHB2N6MK Cooler 10,400 2 45.50 33.25

LET120BHB2N6MK Freezer 12,000 3 61.50 49.25

ADT104BHB2N6MK Cooler 10,400 2 45.50 33.25

LET160BHB2N6MK Freezer 16,000 4 77.50 65.25

ADT052BHB2N6MK Cooler 5,200 1 45.50 17.25

LET120BHB2N6MK Freezer 12,000 3 61.50 49.25

ADT052BHB2N6MK Cooler 5,200 1 29.50 17.25

LET160BHB2N6MK Freezer 16,000 4 77.50 65.25

7
7
7
7
7

1 1

5

7

5

1 1

/8
/8
/8
/8
/8

/8

/8

/8

/8

/8

1

/2 1.0 — 45

1

/2 1.0 7.8 48

1

/2 1.0 — 49

1

/2 1.5 11.7 60

1

/2 1.0 — 49

1

/2 2.0 15.7 81

1

/2 0.5 — 31

1

/2 1.5 11.7 60

1

/2 0.5 — 31

1

/2 2.0 15.7 81

© 2002 Heatcraft Refrigeration Products LLC

3

Evaporator Placement

Figure 3. Evaporator Placement In Cooler/Freezer

Loading Door

1

Freezer

Note: Whenever possible always try to position the evaporator to blow towards the walk-in door.

Never position the evaporator over or adjacent to a door opening.

1

Cooler Freezer

Loading Door

or

Cooler

1

1

Evaporator Minimum Unit Clearance

1 1/2 H

Top View

1 1/2 H

1 1/2 H

Side View

H = Total Height of Unit’s Coil Surface

1 1/2 H

H

2 H

4

1/2 W 1/2 W

W

Condensing Unit Placement

Space and Location Requirements

The most important consideration which must be taken into account when deciding upon the location of air­cooled equipment is the provision for a supply of ambient air to the condenser, and removal of heated air from
the condensing unit or remote condenser area. Where this essential requirement is not adhered to, it will
result in higher head pressures, which cause poor operation and potential failure of equipment. Units must
not be located in the vicinity of steam, hot air or fume exhausts. Corrosive atmospheres require custom
designed condensers.

Another consideration which must be taken is that the unit should be mounted away from noise sensitive
spaces and must have adequate support to avoid vibration and noise transmission into the building. Units
should be mounted over corridors, utility areas, rest rooms and other auxiliary areas where high levels of
sound are not an important factor. Sound and structural consultants should be retained for recommendations.
(Refer to actual building plans for unit locations.)

Figure 4.



3 Feet

(minimum)

Clearance =

3 Feet from

Building

Wall







3 Feet

(minimum)

Clearance to

an Open Block

Wall or

Shrubs.



3 Feet

(minimum)

Clearance for

Contractor to
Service Unit.

5

Refrigeration Piping And Line Sizing

Refrigeration Piping And Line Sizing

The system as supplied by Bohn/Heatcraft, was thoroughly cleaned and dehydrated at the factory . Foreign
matter may enter the system by way of the evaporator to condensing unit piping. Therefore, care must be used
during installation of the piping to prevent entrance of foreign matter. Install all refrigeration system components
in accordance with applicable local and national codes and in conformance with good practice required for the
proper operation of the system. The interconnecting pipe size is not necessarily the same size as the stub-out on
the condensing unit or the evaporator.

The following procedures should be followed:
(a) Do not leave dehydrated compressors or filter-driers on condensing units open to the atmosphere any longer

than is absolutely necessary .

(b) Use only refrigeration grade (ACR) copper tubing, properly sealed against contamination.
(c) Suction lines should slope 1/4” per 10 feet towards the compressor (in direction of flow).
(d) Suitable P-type oil traps should be located at the base of each suction riser to enhance oil return to the

compressor.

(e) For desired method of superheat measurement, a pressure tap should be installed in each evaporator

suction line in the proximity of the expansion valve bulb.

(f) When brazing refrigerant lines, an inert gas should be passed through the line at low pressure to prevent

scaling and oxidation inside the tubing. Dry nitrogen is preferred.

(g) Use only a suitable silver solder alloy on suction and liquid lines.
(h) Limit the soldering paste of flux to the minimum required to prevent contamination of the solder joint internally .

Flux only the male portion of the connection, never the female. After brazing, remove excess flux.

(i) Remove temperature sensor attached to suction line on Beacon II systems before brazing of the

solder joint internally . Flux only the male portion of the connection – never the female. After brazing,
remove excess flux.

(j) Wrap expansion valves with wet rags during brazing to the liquid line.

CAUTION: If the temperature gets too high, these components may be damaged. Heat absorbing
compounds or wet rags must be used to protect the expansion valve when brazing to the refrigerant
piping/line connections, and the suction line sensor must be removed per above instructions.

(k) Do not use “bull head” tees. This will cause oil return problems and can cause poor performance.
(l) If isolation valves are installed at the evaporator, full port ball valves should be used.

Table 3. Recommended Line Size In Equivalent Lengths

Model Room Max. Max. Suction Line Liquid Line

Riser 25’ 50’ Plus 50’ 25’ 50’ Plus 50’

MAC3X

MAC4X
MAC5X

MAC7X
MAC8X

Freezer 7/8” 7/8” 7/8” Consult Factory 3/8” 3/8” Consult Factory

Cooler 5/8” 5/8” 5/8” Consult Factory 3/8” 3/8” Consult Factory

Freezer 7/8” 7/8” 7/8” Consult Factory 3/8” 3/8” Consult Factory

Cooler 5/8” 5/8” 5/8” Consult Factory 3/8” 3/8” Consult Factory

Freezer 1 1/8” 7/8” 1 1/8” Consult Factory 3/8” 3/8” Consult Factory

Cooler 5/8” 5/8” 5/8” Consult Factory 3/8” 3/8” Consult Factory

Freezer 7/8” 7/8” 7/8” Consult Factory 3/8” 3/8” Consult Factory

Cooler 7/8” 7/8” 7/8” Consult Factory 3/8” 3/8” Consult Factory

Freezer 1 1/8” 7/8” 1 1/8” Consult Factory 3/8” 3/8” Consult Factory

Cooler 7/8” 7/8” 7/8” Consult Factory 3/8” 3/8” Consult Factory

Remote Precharged Circuits

The remote precharged circuits are provided with a factory holding charge of R-404A. The system charge is
located in the appropriate drink and ice machines. Schrader valve fittings are provided for liquid line charging
at the condensing unit. Consult the appropriate drink and ice machine manufacturers for details on
installation of precharged lines.

6

Refrigeration Piping

Suction Lines

NOTE: If the suction line must rise to the point higher than the suction connection on

the evaporator, a suction line trap at the outlet of the evaporator must be provided.

Horizontal suction lines should slope away from the evaporator toward the compressor at the rate of 1/4’ per
10 feet for good oil return.

Suction lines that are outside of refrigerated space must be insulated. See “Line Insulation” for more
information.

Suction Line Risers

NOTE: To provide proper oil return, a suction trap must be provided at the base of

all suction risers.

Prefabricated wrought copper traps are available, or a trap can be made by using two street ells and one
regular ell. The suction trap must be the same size as the suction line. For long vertical risers, additional
traps may be necessary. Generally, one trap is recommended for each length of pipe (approximately 20 feet)
to insure proper oil movement. See Figure 5 below for methods of constructing proper suction line P-traps.

Figure 5. Suction P-traps

Condensate Drain Lines

Copper drain lines should be used and properly protected from freezing. In running drain lines, provide a
minimum of 4 inches per foot pitch for proper drainage. Drain lines should be at least as large as the
evaporator drain connection. All plumbing connections should be made in accordance with local plumbing
codes. All condensate drain lines must be trapped, and run to an open drain. They must never be connected
directly to the sewer systems. Traps in the drain line must
be located in a warm ambient. See Figure 6. We
recommend a trap on all evaporators. Traps located
outside, or extensive outside runs of drain line must be
wrapped with a drain line heater. The heater should be
connected so that it is continuously on. The drain line must
be insulated to prevent heat loss. A heat input of 20 watts
per lineal foot of drain line for 0ºF (-18°C) room applications
and 30 watts per lineal foot for -20°F (-29°C) rooms is
satisfactory.

Inspect the drain pan periodically to insure free drainage of
condensate. If the drain pan contains standing water, check
for proper installation. The drain pan should be cleaned
regularly with warm soapy water.

WARNING: All power must be disconnected
before cleaning. The drain pan also serves as
cover for hazardous moving parts. Operation
of unit without drain pan constitutes a hazard.

Figure 6. Drain Line

NOTE: Always trap drain lines individually

to prevent vapor migration.

7

Refrigeration Piping

Figure 7. Example of Pipe Support

1. Normally, any straight run of tubing must be supported in at least two locations near each end of the run.
Long runs require additional supports. The refrigerant lines should be supported and fastened properly.
As a guide, 3/8 to 7/8 should be supported every 5 feet, 1-1/8 and 1-3/8 every 7 feet; and 1-5/8 and 2-1/8
every 9 to 10 feet.

2. When changing directions in a run of tubing, no corner should be left unsupported. Supports should be
placed a maximum of 2 feet in each direction from the corner.

3. Piping attached to a vibrating object (such as a compressor or compressor base) must be supported in
such a manner that will not restrict the movement of the vibrating object. Rigid mounting will fatigue the
copper tubing.

4. Do not use short radius ells. Short radius elbows have points of excessive stress concentration and are
subject to breakage at these points.

5. Thoroughly inspect all piping after the equipment is in operation and add supports wherever line vibration
is significantly greater than most of the other piping. Extra supports are relatively inexpensive as
compared to refrigerant loss.

Figure 8.

Mac
Unit

Line Insulation

After the final leak test, refrigerant lines exposed to high or low ambient conditions should be insulated to
reduce heat loss or gain and prevent the formation of flash gas in the liquid lines. Suction lines must be
insulated with 3/4’ wall Armstrong “Armaflex” or equivalent. Liquid lines must be insulated with 1/2-inch wall
insulation or better. The insulation located in outdoor environments should be protected from UV exposure to
prevent deterioration of insulating value.

8

Leak Detection And Evacuation

Leak Detection

After all lines are connected, the entire system must be leak tested. The complete system should be pressurized
to not more than 150 psig with refrigerant and dry nitrogen. The use of an electronic type of leak detector is highly
recommended because of its greater sensitivity to small leaks. As a further check, it is recommended that this
pressure be held for a minimum of 12 hours and then rechecked. For a satisfactory installation, the system must
be leak tight.

Within the last several years, manufacturers have developed fluorescent dye leak detection systems for use with
refrigerants. These dyes mix with the lubricant and, when exposed to an ultraviolet light “fluoresce,” indicate the
location of leaks. Copeland has tested and approved the Rigid “System Safe” dye and found it to be compatible
with the compressor materials in systems.

Evacuation

CAUTION: Do not use the refrigeration compressor

It is of the utmost importance that proper system evacuation and leak detection procedures be employed.
Copeland recommends a minimum evacuation to 500 microns. In addition, a vacuum decay test is strongly
recommended to assure there is not a large pressure differential between the system and vacuum pump. Good
evacuation processes include frequent vacuum pump oil changes and large diameter, short hose connections to
both high and low sides of the system preferably using bronze braided hose.

to evacuate the system. Do not start the
compressor while it is in a vacuum.

A good, deep vacuum pump should be connected to both the low and high side evacuation valves with copper
tube or high vacuum hoses (1/4” ID minimum). If the compressor has service valves, they should remain closed.
A deep vacuum gauge capable of registering pressure in microns should be attached to the system for pressure
readings.

A shut-of f valve between the gauge connection and vacuum pump should be provided to allow the system
pressure to be checked after evacuation. Do not turn off vacuum pump when connected to an evacuated system
before closing shut-off valve.

The vacuum pump should be operated until a pressure of 1,500 microns absolute pressure is reached – at which
time the vacuum should be broken with the refrigerant to be used in the system through a drier until the system
pressure rises above “0” psig.

NOTE: Refrigerant used during evacuation can not be vented.

Reclaim all used refrigerant. EP A regulations are constantly

being updated. Ensure your procedures follow correct regulations.
Repeat this operation a second time.
Open the compressor’s service valves and evacuate the entire system to 500 microns absolute pressure.
Raise the pressure to 2 psig with the refrigerant and remove the vacuum pump.

9

Field Wiring

WARNING: All wiring must be done in accordance with applicable codes and local ordinances.

The field wiring should enter the areas as provided on the unit. The wiring diagram for each unit is located on the
inside of the electrical panel door. All field wiring should be done in a professional manner and in accordance with
all governing codes. Before operating the unit, double check all wiring connections, including the factory
terminals. Factory connections can vibrate loose during shipment.

1. The nameplate on the unit is marked with the electrical characteristic for wiring the unit.

2. Consult the wiring diagram in the unit cooler and in the condensing unit for proper connections.

3. Wire type should be of copper conductor only and of the proper size to handle the connected load.

4. The unit must be grounded.

Figure 9. Beacon II Board

Heater

Relay

Fan

Relay

LED

Display

Room

Sensor

Defrost

Sensor

Expansion

Valve

Connection

Selection

Buttons

24 V.

Terminal

Block

Suction

Sensor

Suction

Pressure

10

Beacon II Controller

Installation Tips

• Use a minimum 18 gauge wire for all low voltage connections.

• The Beacon II board get its 24 VAC power supply from a transformer mounted in the electrical end of each

evaporator. On 208-240 volt systems the multi-tap transformer is shipped from our factory wired for 240
volts. If your supply voltage is 208 volt you must change to the 208 volt tap on the transformer.

• Refer to wiring schematic shipped on units for wiring.

• Evaporators are shipped from our factory with a preset box setpoint temperature of 35°F for air defrost and

-10°F for electric defrost. If your box setpoint temperature requirements are different this must be set using
directions outlined under “Room Temperature Control”.

• The suction line temperature sensor MUST be removed from the suction line before brazing the suction

tubing. The sensor MUST then be reinstalled on the suction line after brazing is completed and the tubing
has cooled. Insulate when finished.

• The low pressure switch time delay relay, located in the condensing unit, must be set to one minute.

• Some systems may require the crankcase heater to be energized 24 hours prior to start-up. The Beacon II

should be de-energized for this period by placing it in the SERVICE MODE. This is done by pressing the
“FORCE SERVICE” button twice. To start the system cooling, press the “CLEAR” button.

• Room sensors must be left connected on ALL evaporators.

• A pressure transducer is installed on the evaporator. Do not leak test system above 150 PSI or damage to

transducer could occur.

• Refer to the Beacon II Smart Controller Installation Manual, shipped with the Beacon II Smart Controller,

for installation, programming and monitoring information.

Condensing Unit

The condensing unit control panel contains the relays, contactors, and a terminal block which is appropriately
marked to match the low voltage wiring connections. A sensor for outdoor air temperature measurement is
installed on the condensing unit.

Condensing unit must be installed using proper refrigeration practices and codes. Make sure there is good
airflow and good clearances around unit. See Figure 4, page 5.

Evaporator Unit

The evaporator contains the BEACON II controller(s), electric expansion valve(s), pressure transducer,
distributor(s), orifice(s), transformer and three sensors. These components are all factory mounted and wired.
The three sensors are factory mounted and provide input to the controller from the following: defrost temp.,
suction temp., room temp.

Each evaporator unit must be installed using proper refrigeration practices and codes. Make sure the piping is
correctly sized and properly routed. Liquid and suction lines MUST be insulated. There must also be good
clearance around the unit. See Figure 3, page 4.

11

Beacon II Controller

Refrigerant Line Brazing (

The electric expansion valve and the suction temperature sensor on the suction line are factory installed.
Care must be taken when brazing these lines at the evaporator.

components. Heat absorbing compounds or “wet rags” must be used when brazing the refrigerant
line connections. The suction line sensor should be removed before brazing.

CAUTION

)

Too high a temperature may destroy these

Power Supply

The Beacon II board gets its 24 VAC power supply from a transformer mounted in the electrical end of each
evaporator. On 208-240 volt systems the multi-tap transformer is shipped from our factory wired for 240 volts.
If your supply voltage is 208 volt you must change to the 208 volt tap on the transformer.

VERY IMPORTANT: If the supply voltage to the evaporator is 208 volts, the primary tap of the transformer
must be moved to the 208 volt tap.

If the 24 VAC power supply falls below 18 VAC the system may power down and shut off. When the power
supply is corrected to 24 VAC the system will restart after the four minute hold-off period and resume normal
operation.

This must be done for all the evaporators on that system.

Wiring

Wiring between the condensing unit and the unit cooler(s) will be as follows (see attached wiring diagrams):

• High voltage – There may be high voltage on the defrost heater relay and the fan relay. See unit cooler
spec. plate for ampacity.

• Low voltage – 24V Class II control circuit. A total of five low voltage leads are required to connect the
condensing unit to the evaporator (see wiring diagram). Two of these leads are for connecting the outdoor
temperature sensor. The other three leads are for connecting the compressor relay, service relay and 24V
Common inputs.

• Number of wires in low voltage wiring bundles:

MAC to cooler evaporator - 5
MAC to freezer evaporator - 5
Cooler evaporator to Smart Controller - 6
Freezer evaporator to Smart Controller - 4

• Low voltage wiring must be 18 gauge minimum. For low voltage wiring, maximum distances are:

Condensing unit to evaporator 500 ft.
Smart Controller to evaporator 1,000 ft.

• Alarm circuit – The onboard alarm is a dry set of NC contacts which closes to indicate an alarm. The type
and wiring for the alarm is customer specified. Note that the alarm circuit does not distinguish or indicate
what has caused the alarm.

• All wiring must comply with all applicable codes and ordinances.

All 24 volt wiring must be run separate from the line voltage wiring.

12

Beacon II Controller

Box Temperature Control Settings

• There is an on board room thermostat on the Beacon II board which can be adjusted to the desired
room temperature. The temperature differential is 2°F.

Temperature Differential
When a system is in the cooling mode and the box setpoint is 35°F, the system will continue to cool until
the box temperature gets to 34°F. At this point the compressor will pumpdown and shut off. The system
will restart cooling when the box temperature has risen to 36°F.

It is important to note that Beacon II has a minimum 2-minute “ON” time and a minimum 4-minute “OFF”
time. This means that the system will run in the cooling mode a minimum of 2 minutes even if the setpoint
temperature is met. In applications where the system is grossly oversized, the box temperature could go
below the differential temperature before the system cycles off.

In the “OFF” cycle, the system will be off for a minimum of 4 minutes even if the box temperature goes
above the differential temperature before cooling will be restarted.

• The on board room thermostat is factory set at 35°F for air defrost systems and -10°F for electric defrost
systems.

Refrigerant Charging

The cooler and freezer systems utilize refrigerant side head pressure control. Charge each system by adding
an initial charge of 5 lbs. of R-404a refrigerant to the liquid side of the receiver. This initial charge will allow the
system to start. With the system running, continue to add refrigerant to the system until the sight glass is
clear. Operate system until the cooler/freezer box achieves the desired temperature. The sight glass should
be clear with no bubbles or flashing of refrigerant. Now the additional charge for the flooded condenser is to
be weighed into each system in the amount as shown in Table 4.

Table 4.

MAC3X MAC4X MAC5X MAC7X MAC8X

Ambient Freezer Cooler Freezer Cooler Freezer Cooler Freezer Cooler Freezer Cooler

°F. ZF09 RS64 ZF13 RS43 ZF15 RS43 ZF13 CS10 ZF15 CS10

80 3.0 4.0 3.0 4.0 6.0 4.0 3.0 4.0 6.0 4.0
70 2.0 3.0 2.0 3.0 5.0 3.0 2.0 3.0 5.0 3.0
60 1.0 3.0 1.0 3.0 3.0 3.0 1.0 3.0 3.0 3.0
50 1.0 2.0 1.0 2.0 2.0 2.0 1.0 2.0 2.0 2.0

40 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
30 0.5 1.0 0.5 1.0 1.0 1.0 0.5 1.0 1.0 1.0
20 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
10 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

Start-Up Operation

• Check all wiring connections to be sure they are correct and tight.

• On condensing unit:

- Check the setting of Time Delay relay. It should be set a one minute (the second marker).

- Check the Low Pressure switch setting on freezer units. It must be set to 0 PSIG cutout, 10 PSIG
cut-in to allow positive start and operation, especially in cold ambients. This can be changed to a
higher value in warmer climates. On cooler units, the Low Pressure switch has a fixed setting and
cannot be adjusted.

13

Beacon II Controller

Initial Power On

At the initial application of power to the system, the compressor and the evaporator fans will be in a 4-minute
hold-off cycle and will not start immediately. When there is a call for COOLING, the expansion valve (EEV)
opens, then the compressor is started. The compressor will then run for a minimum of 2 minutes in the “hold­on” cycle. (This means that the compressor will run for a minimum of 2 minutes before shutting off even if the
box temperature is met).

The LED alternately displays
show while the expansion valve is opening. After the compressor starts, the LED will alternately display

TEMPERATURE

When the room thermostat setting is satisfied, and if the compressor ran for at least 2 minutes, the EEV will
close and the compressor will pumpdown and shut off. The evaporator fans will continue to run. The LED will
alternately display

When the room sensor detects a rise in temperature of approximately 2°F, and the compressor has been off
for at least 4 minutes, the EEV will open to its last position then the compressor will start. The valve is then
adjusted as necessary to obtain the setpoint superheat setting. During this time, the compressor will run for a
minimum 2 minutes “hold-on” cycle.

The 4 minute “hold-off” can be bypassed and the system started immediately by pressing the “Reset” button
on the Beacon II board.

and

oFF

Coo

BOX TEMPERATURE

.

and

BOX TEMPERATURE

and

.

MODE

of operation. On a call for cooling,

dLY

will

BOX

Figure 10. Operating Mode Display

oFF

–Off

Coo

– Cooling

Pdn

– Pumpdown

dEF

– Defrost

drn

– Draining

dLY

– Delay

tSt

– Test

SEr

– Service

14

Beacon II Controller

Programming And Reviewing Settings/Changes

The Program Review button is used to program, review and change all program settings for the system.
Press “PROGRAM REVIEW” button. The Setpoint item will appear on the LED. After a few seconds delay

the Setpoint value will display. Each time the button is pressed a different setpoint item is displayed.

PROGRAM

REVIEW

Next, use the “SELECT” knob to change value of Setpoint Item.

SELECT

Next, when the desired value is selected, press the “ENTER” button to place it in program memory. If the
“ENTER” button is not pressed, the value will not be stored in the memory and thus will not be changed.

ENTER

“PROGRAM REVIEW” ITEMS

A-E
rEF
bot
SUP
SLA
dFn
dFF
dFt
dFS
ALH
ALL
ALt
F-C

– Set Defrost Type (
– Set Refrigerant Type (R22, R404A or R507)
– Set Box Temperature (-30°F to +70°F)
– Set Superheat (4°F to 20°F)
– Set Board as a Slave (Yes or No)
– Set Number of Defrosts Per Day (1, 2, 3, 4, 5, 6, 8, 10 or 12 per day)
– Set Defrost Fail-safe Time (10 to 200 minutes)
– Set Defrost End Temperature (40°F to 100°F)
– Set Defrost Delay Start Time (0.5 Hours to 23.5 Hours)
– Set Alarm High Temperature (-40°F to 90°F)
– Set Alarm Low Temperature (-40°F to 90°F)
– Set Alarm Time (2 to 120 minutes)
– Set Fahrenheit/Celsius Temperature Units (°F / °C)

Air

or

ELE

)

15

Beacon II Controller

Programming And Reviewing Settings/Changes (continued)

Use the “PROGRAM REVIEW” button to select these items:

PROGRAM

• Defrost Type –
the system factory defaults for air defrost and electric defrost. (See default settings). Please note that the
refrigerant type
factory default settings.

• Refrigerant Type –

“A-E”

– Selection is made for air defrost or electric defrost coil. This will automatically set

default

for air defrost is R22 and for electric defrost it is R404A. All units are shipped with

“rEF”

– Selection for type of refrigerant – R22, R404A or R507.

Default: Air defrost is R22 and for electric defrost is R404A.

• Box Temperature –

“bot”

– Select box temperature setpoint. Selection range is -30°F to +70-°F.

Default: Electric defrost -10°F and air defrost +35°F.

• Superheat –
measures the evaporator saturation suction temperature and the suction pressure to determine the
superheat. The superheat value at the evaporator can be changed to ensure a 20°F to 30°F superheat at
the compressor.

“SUP”

– Evaporator superheat is controlled by the board on each evaporator. Each board

Default: 8°F.

• Evaporator Board: SLAVE –
programmed to be a MASTER or a SLAVE. Each board is shipped from our factory set as a MASTER.
You must make this change to each SLAVE evaporator. A selection of “YES” is made for this setting.

“SLA”

– On multiple evaporator systems, each evaporator board has to be

Default: MASTER on each board. For a single evaporator system, no change is required.

• Number of Defrosts Per Day –
day – 1, 2, 3, 4, 5, 6, 8, 10 or 12 per day. If no selection is made:

“dFn”

– A selection must be made for the number of defrosts cycles per

Default: Electric defrost is 4 per day and air defrost is 2 per day.

• Defrost fail-safe –
terminated if the defrost end temperature is not attained when this time has expired.

“dFF”

– This is the maximum time allowed for a coil to remain in defrost. Defrost will be

Default: Electric defrost is 30 minutes and air defrost is 40 minutes.

• Defrost End Temperature –

Default: Electric defrost is +60°F and air defrost is +45°F.

• Defrost Delay Start Time –

Default: 0.5 hours to 23.5 hours.

“dFt”

– This is the temperature at which the defrost will be terminated.

“dFS”

– This allows the delay of the start of the defrost.

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