Unpacking and Inspection 1

Safety Considerations 1

Placement of System (Tools Required) 2

Spacing Allowances and Dimensions 3

Condensate Drains 4

Mounting Brackets 4

Blower Assembly 4

Supply & Return Air Grilles 5

Ducting 5

Sea Water Pump and Plumbing 6

Electrical Connections, Grounding and Bonding 7

3 Phase Notice 7

Vector Series Wiring Diagrams 8, 9

Passport II Display Panel Installation 10

Installation Checklist (review prior to installation) 11



Operations Checklist 11

Passport II Control 12

Modes of Operation 12, 13

Programming the Passport II 13, 14

Programmable Parameters 14, 15, 16

Troubleshooting Guidelines 17, 18, 19


Sea Water System, Return Air Filters, Winterization 19

Manufacturers Limited Warranty Agreement 20



Congratulations on the purchase of your Marine Air Systems= VECTOR SERIES air conditioner. No matter which of the following features was the reason for your purchase of this air conditioner, we are sure it will meet your needs and will give you many years of efficient and trouble free use. The VECTOR units are self-contained direct expansion air conditioners designed for marine applications incorporating the following features:


$ High efficiency rotary (7-16K), reciprocating (24K), or scroll (24K) compressors

$ Cupronickel condenser coil

$ Raised lance fin designed evaporator coil

$ Polyurethane coated 2@ deep drain pan with multiple condensate drain locations

$ Anti-vibration base pan

$ Pre-charged and pre-wired systems for easy connections

$ Remote mounted electrical box with fire retardant covers for access and service

$ Rotatable, insulated blower assembly

$ Charge Guard7 ensured environmental protection and system integrity

The PASSPORT II microprocessor based digital controller included with this unit offers the most technologically advanced design specifically for the unique requirements of Marine Air Systems= environmental control systems. The controller has been designed with flexibility and the following Auser friendly@ features customers require for their applications:

$ Non-volatile memory

$ Low voltage display panel

$ Face plate air sensor for accurate temperature control

$ LED cabin temperature displayed in Fahrenheit or Celsius

$ Multiple fan speed selections with high and low limits

$ User selected programs for optimum control

$ Optional outside air temperature sensor

$ Compressor pressure protection

$ Compressor start staging delay for multiple a/c systems

$ Moisture mode cycle for humidity control

$ De-Icing feature to prevent evaporator icing

This manual is intended to provide the information necessary to ensure proper installation, operation, and maintenance of the unit. Improper installation or misunderstood operating procedures can result in unsatisfactory performance and/or premature failure of these units, so before proceeding please read this manual completely.


The VECTOR SERIES a/c units are covered under the existing Marine Air Systems= warranty policy contained in this manual. In the interest of product improvement, Marine Air Systems= specifications and design are subject to change without prior notice.




AEffective July 1, 1992, it shall be unlawful for any person, in the course of maintaining, servicing, repairing, or disposing of an appliance or industrial process refrigeration, to knowingly vent or otherwise knowingly release or dispose of any Class I* or Class II** substance used as a refrigerant in such appliance (or industrial process refrigeration) in a manner which permits such substance to enter the environment. De minimis releases associated with good faith attempts to recapture and recycle or safely dispose of any such substances shall not be subject to the prohibition set forth in the proceeding sentence.@

*Class I substances include CFC-12 **Class II substances include HCFC-22




Marine Air Systems (MAS) is a manufacturer of air conditioning and refrigeration equipment for the marine industry. MAS is committed to innovative technology, competitively priced products and market leadership. The MAS team has many years of experience in the design, manufacture, application and support of marine air conditioning and refrigeration. Our practical experience and design capability allows our application engineers and sales representatives to offer optimum solutions for your environmental control requirements. Marine Air Systems, Inc. is A Member of the Taylor Made Group©.





Your self-contained air conditioner consists of four main components and a refrigerant gas circulating through the system. The BLOWER draws warm cabin air across the fins on the EVAPORATOR where the heat from the air is transferred to the refrigerant in the evaporator coil. As the refrigerant evaporates from a liquid into a gas it absorbs the heat from the cabin air. The COMPRESSOR then compresses the refrigerant gas and pumps it through the outer tube in the CONDENSER COIL. The sea water pump circulates cool sea water through the inner tube in the condenser coil, this cools the refrigerant and condenses it into a liquid. The heat from the refrigerant is exchanged to the sea water and discharged overboard. The liquid refrigerant is then passed through the EVAPORATOR COIL and the cycle repeats. Removing heat from the cabin air lowers its temperature. The cooled air is blown through the ducting and out the supply air grille(s). For reverse cycle heating, the refrigerant flows in the opposite direction through the reversing valve. Heat is transferred from the sea water in the condenser coil to the refrigerant and then to the air blowing through the evaporator into the cabin.





When the equipment is received, all items should be carefully checked against the packing list to ensure all cartons have been received. Move units in the normal Aup@ orientation as indicated by the arrows on each carton. Examine cartons for shipping damage, removing the units from the cartons if necessary. If the unit is damaged, the carrier should make the proper notation on the delivery receipt acknowledging the damage.




Never install your air conditioner in the bilge or engine room areas. Insure that the selected location is sealed from direct access to bilge and/or engine room vapors. Do not terminate condensate drain line within four (4) feet of any outlet of engine or generator exhaust systems, nor in a compartment housing an engine or generator, nor in a bilge, unless the drain is connected properly to a sealed condensate or shower sump pump.


Installation and servicing of this system can be hazardous due to system pressure and electrical components. When working on this equipment, always observe precautions described in the literature, tags and labels attached to the unit. Follow all safety codes. Wear safety glasses and work gloves and place a fire extinguisher close to the work area. The following is a summary of the labels on the unit:












Selecting a good location for your air conditioner is the most important part of your preparations. Be sure to consider the size of the area you are cooling, the air distribution needs, and the size of the unit you have chosen. Keeping in mind that cool air has a tendency to fall, it is highly recommended that you locate the supply air grille as high as possible in the cabin. See diagram below.


The VECTOR unit should be installed as low as possible, BUT NEVER IN THE BILGE OR ENGINE ROOM AREAS. INSURE THAT THE SELECTED LOCATION IS SEALED FROM DIRECT ACCESS TO BILGE AND/OR ENGINE ROOM VAPORS. Installing the unit as low as possible (such as under a V-berth, dinette seat or bottom of a locker) and ducting the supply air as high as possible, creates an ideal air flow condition. This type of installation will prevent short or premature cycling.


The unit should be positioned on a firm, level surface and the condensate drain line should run aft and downward from the unit to a suitable drain location sealed away from any exhaust or bilge vapors. Plan all connections which must be made prior to starting installation, including ducting, condensate drain, cooling water in and out, electrical power connections, location of control panel, and sea water pump placement and plumbing, to assure easy access for installation and servicing.



The following space allowances should be considered when mounting the unit:

1) Allow a minimum of 6@ around the perimeter of the unit in the area of the sea water and condensate drain piping.

2) Allow a minimum of 3@ of air space in front of the evaporator coil for the return air intake if it is adjacent to a bulkhead.

3) Allow a minimum of 3@ of air space for the electric blower motor ventilation.

4) For flexible ducting connection allow 2@ for the mount ring, 1@ for the duct bend radius and add the diameter of the duct to get the total distance as measured from the blower outlet. Note that the blower and duct ring can be rotated either vertically or horizontally.

The above dimensions are suggested minimums. Enough space should be allocated for installation and serviceability.



The VECTOR condensate drain pan is 2@ high with two drain locations. During conditions of high humidity, condensate may be produced at a rate of approximately 2 gallon per hour. With this in mind, it is important to route condensate drains downward to a sump pump. It is not recommended to route condensate drains to the bilge. After the condensate drain installation is complete, test the installation by pouring a quart of water into the pan and checking for good flow.


For installation of the condensate drain:


    1. Remove the aft facing watertight plug from the base pan of the VECTOR unit.

    3. Slip the solid washer and the liquid-seal washer onto the PVC fitting in that order.

    5. Connect the fitting through the exposed hole in the base pan with the locking nut.

    7. Securely tighten with two (2) wrenches to provide a proper seal.

    9. Attach a 5/8" I.D. reinforced hose to the hose barb and secure with double/reversed stainless steel hose clamps.

    11. Install the condensate drain hose downhill from the unit and aft to a sump.

    13. Two drain fittings may be used and the hoses teed together provided there is a minimum 2" drop form the bottom of the base pan to the tee connection.

Note: Do not terminate condensate drain line within four (4) feet of any outlet of engine exhaust systems, nor in a compartment housing an engine, unless the drain is connected properly to a sealed condensate or shower sump pump.




The VECTOR unit is supplied with a stainless steel base pan which also serves as a condensate pan. Mounting clip brackets (4) are provided to secure the base pan onto a flat, horizontal surface.



With the VECTOR you can achieve multi-directional supply air discharge from a single unit by rotating the blower to the desired location. It is ideal for tight installations, as 130° of rotation are available with which to position the blower. Its advanced design allows the blower to be easily removed for rotating or servicing by releasing a single stainless steel clamp and two (2) mounting ring screws. Rotate the blower to allow the most direct flow of air to the supply air grille.



Install the supply air grille as high as possible in a location that will provide uniform air distribution throughout the cabin, grille louvers should be directed upward. The return air grille should be installed as low and close to the a/c unit as possible to insure direct uninterrupted airflow to the evaporator. The return air grille should have a minimum four inches (4") or clearance in front of it, free from any furniture or other obstructions In no instance should a supply air discharge be directed towards a return air grille as this will cause the system to short cycle. Allow for adequate clearance behind the supply air grille(s) for the transition box and ducting connection. The following table shows minimum grille sizes. See the MAINTENANCE section of this manual for return air filter cleaning instructions.




Good air flow is critical for the performance of the entire system. It is highly dependent on the quality of the ducting installation. The ducting should be run as straight, smooth and taut as possible minimizing the number of 90 degree bends (two tight 90 degree bends can reduce airflow by 25%). The following table shows minimum duct diameters and their corresponding supply and return air grille minimum areas in square inches. If a transition box is used, the total area of supply air ducts going out of the box should equal the area of the supply duct feeding the box. To calculate the square inch area of a round duct, multiply the radius by itself (r2) and multiply that number by 3.1416 (p ).









5" dia

5" dia

6" dia

7" dia

8" dia


19.6 sq in

19.6 sq in

28.3 sq in

38.5 sq in

50.3 sq in


88 sq in

98 sq in

140 sq in

168 sq in

280 sq in


40 sq in

50 sq in

70 sq in

84 sq in

140 sq in

The following is a summary of proper ducting connections:

1. Pull back the fiberglass insulation exposing the inner mylar duct hose.

2. Slide the mylar duct hose around the mount ring until it bottoms out.

    1. Screw 3 or 4 stainless steel sheet metal screws through the duct hose into the transition ring. Make sure to catch the wire in the duct hose with the heads of the screws. Do not use band clamps, as the hose will slide off.
    2. Wrap duct tape around the ducting and ring joint to prevent any air leaks.

5. Pull the insulation back up over the mylar to the ring and tape this joint.

6. Remove excess ducting and use the same connection method at the s/a grille.


All ducting should:


    • Be appropriately sized for each application.


    • Run as smoothly and taut as possible.


    • Have as few bends or loops as possible.


    • Be securely fastened to prevent sagging during boat operation.


    • Have all excess ducting lengths trimmed off.


    • Not be flattened or kinked.


    • Insulated when located in high heat load areas (hull side, mechanical compartments, etc.).




Sea water temperature will directly affect the a/c unit’s efficiency. This a/c unit can effectively cool your boat in water temperatures up to 90 F and heat (if reverse cycle option is installed) in water as low as 40 F.

Several guidelines should be followed during the installation of the sea water system. Since the circulation pump is centrifugal and not self-priming, it must be mounted so that it is always at least one foot below the water line regardless of which tack the vessel is on. The pump may be mounted horizontally or vertically, however the discharge must always be above the inlet. The pump head should be rotated toward the direction of water flow. Install the sea water speed scoop intake as far below the water line and as close to the keel as possible in any application, but especially on a sail boat, to keep the intake in the water so that air does not get into the system when the boat heels over. The speed scoop intake must face forward and not be shared with any other pump. A sea cock (shut off valve) must be installed directly on the speed scoop outlet. A sea water strainer is mandatory between the sea cock and pump. Failure to install a sea water strainer will void the pump warranty. The sea water system should be installed with an upward incline from the speed scoop & sea cock, through the strainer, to the inlet of the pump and then up to the inlet of the a/c unit=s condenser coil. The discharge from the a/c unit should then run to the sea water outlet through hull fitting which must be located approximately 18" above the water line. Use only reinforced marine grade hose. All hose connections shall use double/reversed stainless steel hose clamps.

The following is a summary of the sea water system installation:

  1. Install the speed scoop thru-hull inlet as close to the keel and as far below the water line as
  2. possible, facing forward. Bed the scoop with a marine sealant designed for underwater use.

  3. Install a bronze, full flow sea cock on the speed scoop thru-hull inlet.
  4. Install a sea water strainer below the level of the pump with access to filter.
  5. Mount the pump at least one foot below the waterline and above the strainer.
  6. Connect the sea cock, strainer and pump with an uphill run of e" reinforced marine grade hose.
  7. Connect the discharge from the pump uphill to the bottom inlet of the a/c unit=s condenser coil.

Avoid loops, vertical bends (high spots) or the use of 90  elbows with sea water hose. Double clamp all hose connections with stainless steel clamps, reversing the clamps. Use teflon tape on all threaded connections. Connect all metallic parts in contact with sea water to the vessel=s bonding system including

the speed scoop inlet, strainer, pump and the air conditioner.



All a/c units have a terminal strip mounted either inside or outside the electric box. The terminal strip is labeled for proper connections of the electrical supply, ground wires and pump circuits. A wiring diagram is provided in the electrical box and in this manual. The correct size circuit breaker should be used to protect the system as specified on the a/c unit=s data plate label. A minimum of 12 AWG boat cable should be used to supply power to the a/c unit and the sea water pump. All connections shall be made with ring or fork terminals. Turn off a/c power supply circuit breaker before opening electrical box.


Each a/c unit installed requires its own dedicated circuit breaker. If there is only one a/c unit installed, the sea water pump does not require a circuit breaker, the wiring from the sea water pump is connected to the terminal strip at the electrical box. If two or more a/c units use the same sea water pump, the pump wires will be connected to a pump relay panel (PRP) which in turn has its own dedicated circuit breaker. Please see the wiring diagram furnished with the PRP. Connections in the bilge below the waterline should use heat shrink type butt splices.


Field wiring must comply with ABYC electrical codes. Power to the unit must be within the operating voltage range indicated on the data plate in the electric box. Properly sized fuses or HACR circuit breakers must be installed for branch circuit protection. See data plate for maximum fuse/circuit breaker size (mfs) and minimum circuit ampacity (mca). All units must be effectively grounded to minimize the hazard of electrical shock and personal injury. The following are to be observed:

1. AC (alternating current) grounding (green wire) must be provided with the AC power conductors and connected to the ground terminal (marked AGRND@) at the AC power input terminal block of the unit(s), per ABYC standard E-8, or equivalent.

2. Connections between the vessel=s AC system grounding conductor (green wire) and the vessel=s DC (Direct Current) negative or bonding system should be made as part of the vessel=s wiring, per ABYC standard E-9, or equivalent.

3. When servicing or replacing existing equipment that contains a chassis-mounted Aground@ stud, the service person or installer must check the vessel=s wiring for the existence of the connection required in item 2 above.

ABYC standards are available from: American Boat and Yacht Council

3069 Solomon=s Island Rd.

Edgewater, MD 21036 Telephone: (410) 956-1050


The a/c unit must be connected to the ship=s bonding system to prevent corrosion due to stray electrical current or voltage. All pumps, metallic valves and fittings in the sea water circuit that are isolated from the a/c unit by PVC or rubber hoses must be individually bonded to the vessels bonding system also. This will help eliminate any possibility of corrosion due to stray current or voltage.






It is extremely important to insure that wiring and phase sequencing of a three phase power source is correct. Marine wiring standards call for power source phases L1, L2, and L3 to be color-coded BLACK, WHITE, and RED, respectively. These must be connected to the unit with the proper sequence, otherwise, it will not operate properly. If the wiring sequence is incorrect, the unit’s compressor (Scroll type only) and pump (if applicable) will run in the reverse direction at a significantly increased noise level.







Before mounting the Passport II digital display panel touch pad, consider the location. The air sensor built into the display panel will provide excellent room air temperature sensing given a proper installation. The display panel should be mounted on an inside wall, slightly higher than mid-height of the cabin, in a location with freely circulating air where it can best sense average temperature. The cut out size for the display panel is 3d" wide by 2:" high. Do not mount the display in direct sunlight, near any heat producing appliances or in a bulkhead where temperatures radiating from behind the panel may affect performance. Do not mount the display in the supply air stream. Do not mount the display above or below a supply or return air grille. Do not mount the display behind a door, in a corner, under a stairwell or any place where there is no freely circulating air. Mount the display within display cable length (custom lengths available) of the air conditioner. Plug the cable into the circuit board in the electrical box and into the back of the display panel. Secure the display panel to a bulkhead with the adhesive strips provided, clean the mounting surface with isopropyl alcohol only prior to placement (test alcohol on hidden portion of surface first). If the adhesive strips cannot be used, use #6 truss head screws to mount the display. The panel has predrilled holes in each corner that can be accessed by peeling back the adhesive strips. Carefully & slowly drill 5/32" holes through the front of the lexan cover lining up with the predrilled holes in back. Do not use a screw gun and do not over-tighten screws when mounting panel. Over-tightening screws will damage the lexan cover. If a proper location for room temperature sensing cannot be found for the display, an optional remote air sensor may be used. Mount the remote air sensor in the return air stream behind the return air grille/opening and plug its cable into socket #J2 on the circuit board (socket nearest the corner of the board). Installing the remote air sensor will normally override the face plate sensor, but it is possible to utilize both sensors alternately, see programmable parameter AU 8@ before mounting panel or sensor. If the remote air sensor cable is not needed for return air temperature sensing, it may be used to monitor outside air temperature. Plug the cable into the other 6-pin socket #J3. Mount the sensor outside but not in direct sunlight. Optional fifteen foot outside air sensor cables are available if needed. Do not staple any cables when mounting.


INSTALLATION CHECKLIST (review prior to installation)


Sea Water cooling system:

G Speed scoop located as far below the water line and as close to the keel as possible

G Shut off valve and speed scoop properly sealed and tight

G Sea water pump at least one foot below water line and securely mounted

G Strainer mounted below pump with access to filter

G Double/reversed stainless steel hose clamps on all hose connections

G Teflon tape on all threaded connections

G Hose runs uphill from speed scoop and sea cock to strainer, pump and a/c unit, then

downhill from a/c unit to overboard discharge

G Water flowing freely from overboard discharge while pump is running


G Not in engine room or bilge areas, must be sealed away from exhaust or fumes

G Proper spacing allowed around unit

G Attached to solid level platform with hold down clips provided

G Condensate drain routed aft and down hill to a sealed sump (not bilge)

G Blower rotated toward supply air grille


G All butt connections on pump wire tightly crimped and heat shrunk

G AC power source installed and grounded/bonded in accordance with ABYC standards

G Control wires connected to terminal strip with fork terminals

G Circuit breakers sized according to specifications on the data plate label

G Passport II display cable is connected at both ends.

Grilles and Ducting

G Supply air grille mounted as high as possible

G Return air grille mounted as low and as close to the a/c unit as possible

G Return air grille mounted away from bilge vapors or exhaust fumes

G Ducting is pulled taut, straight, smooth and properly connected with no excess




G Ensure sea water intake ball valve is open.

G Turn on the A/C circuit breaker. If the sea water pump has its own circuit breaker, turn that on too.

G Turn the system on by pressing the POWER button.

G Set the desired cabin temperature (set point) by using the UP or DOWN buttons.

G Check for a steady solid stream of water from the overboard discharge.

G Verify that there is steady airflow out of the supply air grille.

G If the unit does not appear to be operating properly, refer to troubleshooting guidelines.

Note: Do not turn the unit off and immediately turn it back on. Allow at least 30 seconds for refrigerant pressure equalization.



POWER BUTTON: Press and release to turn unit on and off.

NOTE: To Apress and release@ a button, press and hold for one second and then release.

FAN BUTTON: Press and hold until the letter AA@ appears for automatic fan speed or the numbers A1@ (slow) through A6@ (fast) appear for manual fan speed. Fan may be used while a/c is off.


UP & DOWN BUTTONS: Press and hold either button until desired temperature (set point) is displayed. Press either button momentarily to show current set point. Range = 601-851F.


COOL LED: Lights when the compressor is running in cool mode or in automatic mode while cooling.


FAN LED: Lights when fan is on in manual mode.


HEAT LED: Lights when the compressor is running in heat mode, in automatic mode while heating or if optional electric heat is installed and operating.


DISPLAY WINDOW: Shows current cabin temperature. Can show outside air temperature if the optional O.A.T. sensor is installed. Also used in viewing and setting program parameters.


AIR SENSOR: Cabin temperature is detected by the face plate air sensor, located in the bottom edge of the display. A remote air sensor can be installed if needed. Installing the remote air sensor will normally override the face plate sensor, but it is possible to utilize both sensors alternately (see program U 8).


BLANK DISPLAY FOR NIGHT-TIME OPERATION: Press the FAN and DOWN buttons simultaneously to blank the display for night time operation. The appropriate LEDs will remain lit during cooling and heating. When the desired temperature has been achieved, the middle segment of the display window will remain lit to indicate that the system is on. Press any button to return to normal display mode.


OUTSIDE AIR TEMPERATURE: When the optional outside air sensor is installed, press the UP and DOWN buttons simultaneously to display the outside air temperature. The outside air sensor should not be mounted in direct sunlight.




COOL ONLY MODE: When the Passport II is configured for cool only mode, only cooling systems will be operated as required. When the temperature drops below the set point the system will not automatically switch into the heating mode.


HEAT ONLY MODE: When the controller is programmed for heating mode, only the heating system will be selected for operation as required. Should the temperature rise above the set point the system will not switch to the cooling mode automatically.

AUTOMATIC MODE: When the controller is configured for the automatic mode, both heating and cooling will be supplied as required. The heat and cool LED indicators will light according to which mode is operating. Temperature differential in a given mode will be maintained at 2° F, however, a 4° F difference is required to allow the control to change modes.


HUMIDITY MODE: While the system is on, press the POWER and the DOWN buttons simultaneously to enter the humidity or moisture control mode. The characters AII-1@ will appear in the temperature display. Every four hours, the fan is started and air is circulated for thirty minutes. During this time the air temperature is sampled and entered into memory. The cooling cycle is then started and continues until the temperature is lowered 2°F. The compressor is allowed a maximum of one hour running time to reach the desired temperature. Four hours after the temperature is satisfied or the compressor times out, the cycle is repeated. During the cycle, the cool LED will be lit when the compressor is running. Humidity mode is provided to maintain a specific temperature and humidity range when the vessel is unoccupied for extended periods of time.


AUTOMATIC FAN MODE: Press and hold the FAN button until the letter AA@ appears in the display window. Automatic fan mode allows the control to determine fan speeds based on the room temperature. The closer the room temperature is to the set point, the slower the fan will run. This permits a balance between the most efficient temperature control and the slowest (quietest) fan speed. The fan LED will not be lit during automatic fan mode.


MANUAL FAN MODE: Press and hold the FAN button during normal operation to select one of the six manual fan speeds available. Six (6) is the highest and one (1) represents the lowest speed available. When a manual fan speed has been selected the fan LED will be lit.

NOTE: High and low fan speeds can be further tailored to suit the user by adjusting the fan limits. See programming modes AU 2@ and AU 3@.


CIRCULATION MODE (FAN ONLY): With the system off, press and hold the FAN button until the desired fan speed is indicated by the numbers A1@ (slow) through A6@ (fast). To turn the fan off press and hold the FAN button until the number A0@ appears in the display window.




The program mode is used to adjust operating parameters to tailor the system for efficient operation and to allow for user flexibility. Installation variables such as ducting, sensor location and system layout effect the operation of the overall system. Custom programming allows the system to operate as efficiently as possible in any given installation.

TO ENTER PROGRAM MODE: With the system off, press and hold the POWER button for five seconds until the letter AU@ appears in the display window. Release the button and the first parameter setting appears followed by AU 1@.


TO UNLOCK PROGRAM MODE: After entering the program mode, simultaneously press and release the POWER and DOWN buttons.


TO SELECT PROGRAM PARAMETER: Press and hold the FAN button to scroll through the parameters indicated by the program number. Programs are described in the following table.


TO CHANGE THE PROGRAM PARAMETER: Use the UP and DOWN buttons to select data or set the desired limits. The range of parameter settings is listed in the following table.


TO RESET DEFAULT SETTINGS: With the system off, press and hold the POWER button for ten seconds until the software version number (A##) appears in the display window.


TO LOCK NEW DEFAULT SETTINGS: Once the desired program changes have been made and before exiting the program mode, simultaneously press and release the UP and DOWN buttons. Locking new defaults will render the factory defaults obsolete. Make note of the new defaults in the following chart for future reference.


TO EXIT PROGRAM MODE: Press the POWER button or press no button for sixty seconds. The software version number is displayed for one second prior to exiting the program mode.















U 1


Operating Mode


0 or 1*

0 = Automatic Mode

1 = Cool Only Mode

2 = Heat Only Mode

U 2

High Fan Speed Limit


56 – 85

U 3

Low Fan Speed Limit


30 – 55

U 4

Compressor Staging Time Delay

15 or 135*

5 – 135 Seconds

U 5

Temperature Calibration


± 10° F


U 6

Compressor Fail-Safe Protection

HHH = high freon pressure

PPP = low freon pressure (option)



0 = Fail Safe Protection OFF

1 = Continuous Restarts, No Display

2 = Continuous Restarts, With Display

3 = 3 Failures w/Display, Reset Required

U 7

Fahrenheit or Celsius Temperature Display


0 = ° F

1 = ° C

U 8

Use Alternate Air Sensor

And/or Face Plate Air Sensor


0 = Alternate Sensor Override

1 = Toggle Between Both Sensors

U 9

Reversed Fan Speeds

During Heating


0 = Fan speed decreases as

set point is approached.

1 = Reversed Fan Speeds


Continuous Fan Operation or

Cycle Fan with Compressor


0 = Cycle Fan with Compressor

1 = Continuous Fan Operation


Reverse Cycle or Electric Heat

Option Installed


0 = Reverse Cycle Heat

1 = Electric Heat


Fan Motor Type Selection

Set at


0 = Shaded Pole Fan Motor

1 = Split Capacitor Fan Motor


De-Icing Cycle


0 = Off, 1 = One Minute

2 = Two Minutes, 3 = Three Minutes

* Specific default settings for cool only a/c units (no heat option installed) should not be changed.

** Default parameter settings may be reprogrammed by user, enter new default settings in this column.


U 1 OPERATING MODE: The operating mode is used to select heating, cooling, or automatic modes. Zero (0) selects automatic mode, one (1) selects cooling mode and two (2) selects heating mode. Systems that do not have heating capabilities should be programmed for cooling mode (1). The factory default is zero (0) for automatic mode.


U 2 HIGH FAN SPEED LIMIT: The high fan speed limit can be tailored to suit various motors and operating conditions. The range of values is 56 through 85 in arbitrary units. The factory default is 85.

U 3 LOW FAN SPEED LIMIT: The low fan speed limit determines the lowest output allowed for the low fan speed. The range of values is 30 through 55 in arbitrary units. The factory default is 50.


Both the high and low fan limits may be adjusted as follows: While the system is off, start the fan by pressing and holding the FAN button until the number A1@ appears in the display. Enter the program mode while the fan is running and select AU2@ or AU3@. Raising and lowering the fan limits while the fan is running allows the programmer to experience fan speed changes as they are made. Once the high and low fan speed limits are set, the system will automatically reprogram itself to produce six equally spaced fan speeds between them.


U 4 COMPRESSOR STAGING TIME DELAY: The compressor staging time delay is provided for use where more than one a/c system is being operated from the same power source. Setting the staging delays at different intervals allows for only one compressor to start at a time to lessen the amperage load on the power source. The minimum delay is five (5) seconds and the maximum is one hundred thirty five (135) seconds. The factory default setting is fifteen (15) seconds.


U 5 TEMPERATURE CALIBRATION: Use this feature to calibrate the air sensor within a range of "10°F. The factory default is 0°F.


U 6 COMPRESSOR FAIL-SAFE PROTECTION: This feature is provided to monitor the refrigerant circuit. When a high head pressure condition occurs the display will flash AHHH@, when the refrigerant system is low on pressure APPP@ will flash only if the optional low pressure switch is installed. This display indicates that the system requires maintenance. See the TROUBLESHOOTING GUIDELINES in this manual. The four parameter settings are:

Zero (0): Turns off all protection, no action is taken and no message displayed.

One (1): No message displayed with 90 seconds between continuous restarts.

Two (2): Message displayed with 90 seconds between continuous restarts.

Three (3): Message displayed with three 90 second restarts, manual reset is required.

The factory default is three (3).


U 7 FAHRENHEIT OR CELSIUS TEMPERATURE DISPLAY: The PASSPORT II can display temperature in either degrees Fahrenheit (° F) or degrees Celsius (° C). Setting to zero (0) displays ° F and setting to one (1) displays ° C. The factory default is zero (0).


U 8 ALTERNATE AIR SENSOR OPERATION: Installing an alternate remote air sensor will override the face plate (digital display panel touch pad) air sensor unless this program parameter is set to one (1). This program is utilized only if the a/c unit is used to supply air to two different locations, i.e., salon and aft cabin, and if it is desired to control the temperature from these locations at different times of the day, i.e., day and night. The remote air sensor should be installed in the return air stream behind the return air grille. In this case, the display panel would be in a different room than the a/c unit. If the a/c unit and display panel are in the same room, mount the remote air sensor in the other room using the same guide lines for locating the display panel as stated in APassport II Display Panel Installation@ in this manual. To activate program, set parameter to one (1). To toggle from sensor to sensor, simultaneously press the fan and up buttons while a/c unit is on. When the alternate air sensor is operating, the letter AA@ will appear in the display window while viewing the set point. To view set point press either up or down button. The factory default is zero (0).

U 9 REVERSED FAN SPEEDS DURING HEATING: During normal operation in the cooling mode with the fan speed set to AA@ (automatic), the fan speed is reduced as the set point temperature is approached. During heating, this is not always the preferred method of operation. When this parameter is set to one (1), the fan speed will increase as the set point is approached during heating. This will reduce head pressure by increasing air flow across the coil as the set point is approached. As the ambient cabin temperature rises, the fan speed will slow which will increase head pressure making the air seem warmer. Setting the parameter to zero (0) will cause the fan speed to decrease as the set point is approached during heating, as it does in the cooling mode. The factory default is one (1).


U10 CONTINUOUS FAN OPERATION OR CYCLE FAN WITH COMPRESSOR: The fan can be programmed to run continuously while the system is on, or can be allowed to cycle with the compressor. When cycled with the compressor, the fan will only operate when cooling or reverse cycle heating is called for. To cycle the fan with the compressor, select zero (0). To operate the fan continuously, select one (1). The factory default is one (1).


U11 REVERSE CYCLE OR ELECTRIC HEAT: Units not equipped with reverse cycle heating, or reverse cycle units operating in sea water temperatures below 401F, may need to have electric heaters added. IMPORTANT: the Passport II circuit board reversing valve output is use to control the optional electric heater. The valve output relay can only carry 6 amps, therefore, a heavy duty contactor must be installed to carry the electric heater current. Select one (1) for the electric heat option, select zero (0) for reverse cycle heating. The factory default is zero (0).


U12 FAN MOTOR TYPE SELECTION: This feature allows the controller to be programmed for the type of motor on the unit’s fan. Zero (0) selects a shaded pole motor, which is used on most Vector units. Select one (1) for units having AHV@ or AEBM@ in their model number, these units have a split capacitor motor. The controller has been factory programmed for the appropriate motor type.


U15 DE-ICING CYCLE: Under certain extreme conditions ice may build up on the evaporator coil. Running the a/c at a low set point with the hatches and doors open on a hot humid day would be an example of this. If the a/c runs for an hour in cool mode and during that time the ambient temperature does not change by more than one degree, the de-icing cycle will activate turning the unit into reverse cycle heat for one to three minutes depending on the setting. The programmable parameter may be set at zero (0), one (1), two (2), or three (3) minutes. If the evaporator coil is still iced up after three minutes, see the trouble shooting section of this manual. The factory default is zero (0), which is off.







Will not start.

A/C circuit breaker is off.

Turn circuit breaker on at ship=s panel.



Wrong wiring at terminal strip.

Check wiring diagram; correct if necessary.



Input line voltage is insufficient.

Check power source (shore/generator) for proper voltage. Check wiring and terminals for proper sizes and connections.

Passport II display panel is not lit.

8-pin display cable plugs are not making contact (unplugged, dirt, bent, or broken pins).

With POWER OFF at the circuit breaker, remove connector and inspect. If damaged, replace connector or entire display cable.

No cooling or heating.

Temperature set point is above (in cooling) or below (in heating) ambient temperature.

Lower or raise set point.



Passport programmed for heat or cool only.

Reprogram parameter U1 for appropriate mode: cooling, heating or auto.



Low sea water temperature (in heating).

Reverse cycle operation is affected by the temperature of the sea water, as the water temperature is reduced so is the capacity of the output of the warm air. If electric heat is installed, reprogram parameter U11.



Obstructed sea water flow.

Clean sea water strainer. Check for obstructions at speed scoop thru-hull inlet. Check for a good steady flow from the overboard discharge.



Sea water pump may be air-locked.

Remove hose from pump discharge to purge air from line.



Electric heat option not operating properly.

The Passport board has a 6 amp relay for reverse cycle, if electric heat is installed, a contactor must be used to carry the heater current. Check wiring and see programmable parameter U11.



Fan is not running.

See below



Coil is iced (in cooling).

See below



AHHH@ is displayed on panel.

See below



APPP@ is displayed on panel.

See below

Fan is not running.

Passport II is programmed for fan cycling with compressor.

Reprogram parameter U10.

No air flow.


Air flow is blocked.

Locate obstructions, clean return air filter and grille.






No air flow.

Coil is iced.

See below

Unit switches to heat while in cool mode.

De-icing feature enabled due to coil icing up.

See below

Coil is iced.

Thermostat set point is too low.

Raise set point.*



Improper air flow.

Clean return air filter or remove obstructions from return air stream. Check for crushed or restricted ducting, ducting must be as straight and taut as possible. If problem persists program low fan speed parameter U3 for maximum value (55).*



Supply air is short-cycling.

Redirect supply air so that it is not blowing into the return air stream.*



Humidity level too high.

Close hatches and doors*.





* Read programmable parameter U15 and reset. If de-icing cycle does not melt ice, switch a/c to heat until ice melts or use hair dryer to melt ice.

AHHH@ is displayed on Passport panel.

High pressure switch is open (in cooling) due to improper sea water flow.

Strainer or intake may be plugged, sea cock may be closed, check sea water hose for kinks or collapses. Verify pump operation, check pump circuit breaker if applicable.



High pressure switch open (in heating) due to improper air flow.

Clean return air filter or remove obstructions from return air stream. Check for crushed or restricted ducting, ducting must be as straight and taut as possible. If problem persists program low fan speed parameter U3 for maximum value (55). Reprogram parameter U9 for A1@ to reverse fan speeds.

APPP@ is displayed on Passport panel.

Low pressure switch is open due to low sea water and/or low return air temperatures.

Try restarting the a/c unit, the optional low pressure switch has a ten minute time delay that may be in effect.



Low pressure switch is open due to loss of refrigerant.

Check a/c unit for refrigerant oil leakage, call service technician (see back of manual).

System runs continuously. (continued)

Improper Passport air sensor location.

Verify display head location with criteria found in this manual. Install alternate air sensor if necessary.






System runs continuously.

Set point temp. is improperly programmed, too low for cooling or too high for heating.

Raise or lower set point.



Port hole or hatch open.

Close all port holes and hatches.




Sea Water Strainer

Insure that your pump receives adequate sea water flow by regularly cleaning the strainer basket. Periodically check the overboard discharge for a steady stream of water. Check sea water intake speed scoop for obstructions. Make sure hoses are not looped, kinked or crushed.


Sea Water Pump

If the capacity of your air conditioning system is greater than or equal to 48,000 BTU/hr, the sea water pump is most likely air cooled and will need occasional oiling. See manufacturer’s labeling on the pump for maintenance instructions.


Condenser Coil Cleaning

Coils can become fouled over a period of time due to marine growth or scale build-up. This both obstructs water flow and prohibits proper heat transfer. To clean coils, flush with a 5% muriatic or hydrochloric acid and fresh water solution. Disconnect system hoses from coil and pump solution through until clean. Rinse with fresh water and reconnect hoses. Follow manufacturer’s safety guidelines for all cleaning solutions.


Return Air Filters

Check the return air filter about once a month and clean as necessary. To clean the filter, remove it from the unit/grille, rinse with water, air dry and reinstall.



There are several methods of winterization, some of which work better than others. The four various methods employed using a 50/50 non-polluting biodegradable anti-freeze/water solution are:


  1. Pumping of anti-freeze solution into the overboard thru-hull fitting, and discharging through the intake thru-hull fitting.

  3. Use of the sea water pump to pump anti-freeze solution through the system and discharging through the overboard thru-hull fitting. Close sea cock, remove hose from strainer discharge, raise hose above pump (so pump does not lose its prime) and pour in anti-freeze solution. Pump solution through system. The strainer and hose to sea cock will also need to be drained of water.

  5. Use of pressurized air injected at the overboard discharge fitting and the water being discharged through the sea water intake fitting.

  7. Use of pressurized air to force water from the intake through the overboard discharge.

Any method which causes the anti-freeze solution to flow downward is the method of choice. By this means, the anti-freeze solution will displace any water trapped and eliminate the possibility of freezing in hidden areas. In addition, since the sea water pump utilizes a magnetically driven impeller, the impeller should be removed from the wet end assembly, wiped with an alcohol solution, and stored in a warm, dry area until commissioning takes place.

Note: Collect all discharged liquids and recycle or dispose of in a proper manner.



Every precaution has been taken in the preparation of this manual to insure its accuracy. However, Marine Air Systems assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of this product and information contained herein.

Copyright© 1998 Marine Air Systems, All Rights Reserved