Dometic Marine Air Systems Fx-Maxx SDL User manual

Chilled Water Systems
Revised: 4-1-04
L-2337

Fx-Maxx SDL Air Handler Control Operations Manual
L-2337 Page 12
Revision: 07 4-1-04
Contents
BASIC OPERATION ................................................................................................................................... 1
DESCRIPTION OF OPERATION .................................................................................................................... 2
OPERATOR CONTROLS AND DISPLAY PANEL ....................................................................................... 3 & 4
DUAL BUTTON FUNCTIONS ....................................................................................................................... 5
MODES OF OPERATION ...................................................................................................................... 5 & 6
MOISTURE MODE ..................................................................................................................................... 6
FAN MODES ............................................................................................................................................ 6
ENTERING THE PROGRAM MODE ................................................................................................................ 7
DEFAULT PROGRAM TABLE ....................................................................................................................... 8
SPECIFICATIONS ....................................................................................................................................... 9
WIRING D IAGRAM .................................................................................................................................. 10
CONVECTOR APPLICATION ...................................................................................................................... 11
NOTES:
All items labeled COMP should be considered Electric Heater applications.
When the Alternate Air Sensor is required the Outside Air Sensor is not available
Copyright © 2004, All Rights Reserved
No part of this publication may be reproduced, translated, stored in a retrieval system, or transmitted on any form
or by means electronic, mechanical, photocopying, recording or otherwise without prior written consent by
Dometic Corporation.
Every precaution has been taken in the preparation of this manual to insure its accuracy. However, Dometic
Corporation assumes no responsibility for errors and omissions. Neither is any liability assumed for damages
resulting from the use of this product and information contained herein.

Fx-Maxx SDL Air Handler Control Operations Manual
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BASIC OPERATION
POWER BUTTON Press the power button once to toggle the unit
to the on mode. Press the power button again to toggle the unit to the
off mode.
FAN BUTTON Press and release the fan button to advance from
auto to manual fan. Press and release to increase the manual fan
speeds, 1 through 6. Press and release again returns to the auto fan
mode. The selected fan mode is indicated by the Auto and Manual
fan LED's
UP BUTTON Momentarily press and the set point will appear in the temperature display. The set
point increases one degree each time the up button is pressed and released.
DOWN BUTTON Momentarily press and release to display the set point. The set point is
decreased one degree each time the down button is pressed and released.
MODE BUTTON The mode button is used to select one of 4 Operating Modes. Press and release
to advance to the next mode. Continue to press and release until the desired Operating Mode is
reached. The mode selected is indicated by the Mode LED.
TEMP SELECT BUTTON Press and release to view inside air temperature, outside air temperature
or set point. The appropriate LED will be lit indicating the temperature is displayed.
THREE DIGIT DISPLAY The room temperature is displayed whenever the control is turned on. The
display provides a readout of the inside ambient air temperature and the set point.
HEAT MODE LED The heat mode LED is lit when Heating is selected.
COOL MODE LED The cool mode LED is lit when the Cooling is selected.
AUTO LED The auto LED is lit when the Automatic Heating or Cooling Mode is selected. The
control will automatically switch to heating or cooling when this mode is selected.
MOISTURE CONTROL LED The moisture LED is lit when the Moisture Control is selected.
MANUAL FAN LED The manual fan LED is lit when a manual fan speeds is selected.
AUTO FAN LED The auto fan LED is lit when automatic fan speed operation is selected.
FAN SPEED BAR GRAPH There are six [6] individual fan speed LED's. Each LED represents
one [1] fan speed. Low fan [1] is indicated by illuminating the first LED. High fan speed is indicated
by illuminating all six [6] LED's.
WATER VALVE STATUS LED The system operating status [ Water Valve Open or Closed ] is
indicated by turning On the right most decimal point in the 3 Digit Display.

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OVERVIEW
Fx-Maxx SDL is a user friendly, easy to operate, programmable temperature control.
Press the ON/OFF button once to engage the system. The display indicates room temperature when the
system is on and the display is blank when the system is off.
Press and release the Mode Button until the desired Mode LED is illuminated.
Set the room temperature by pressing the up or down button. The set point can be viewed by momentarily
pressing and releasing the up or down button.
Fan speed operation is automatic. The fan speed decreases as room temperature is approached. The fan
will operate at low speed when set point is satisfied. Manual fan speeds can be selected by pressing the
Fan Speed Button and selecting the desired fan speed. The fan will operate at the speed selected and will
not change speeds with room temperature.
The fan can be programmed to cycle on and off with the Heating and Cooling demand. Normally the
automatic fan speed operation is reversed in the heating mode, however, the fan speeds can be
programmed to operate the same as in the cooling mode.
NORMAL HEATING OR COOLING CYCLE
When heating or cooling is called for the water valve switches to the appropriate mode. Four [4]
seconds later the automatic fan control adjusts the fan to the proper speed. When the demand is
satisfied, the water valve cycles off and the fan returns to low speed. If cooling is required, the water
valve will not open unless adequate cooling water is available. The fan will remain in low speed
until adequate cooling water is available. If heating is required the valve will not open unless
adequate heating water is available. The fan remains in low speed until adequate heating water is
available. The water temperature can be viewed by simultaneously pressing the Up and Down
Buttons while in the On Mode. Heat will be supplied when no heating water is available if the
Optional Electric Heater [Electric heating element] has been installed and programmed.
While in a Heating or Cooling Mode the controller will maintain a two degrees Fahrenheit (2 °F)
temperature variation. A four degree swing is required to cause the unit to shift to the opposite mode.
Once in a new mode, Heating or Cooling, Fx-Maxx SDL Air Handler Control will maintain a two degree
differential.
MOISTURE MODE
While in the on mode, press the Mode Button until the Moisture Control LED is lit. The first cycle
will start in 1 minute. Every 4 hours, the fan is started and air circulated for 30 minutes. During this
time the air temperature is sampled and entered into memory. The cooling cycle is started and
continues until the temperature is lowered 2 ° F. The system is allowed a maximum of one hour
running time to reach the desired temperature. Four hours after the temperature is satisfied or the
Cooling Mode times out, the cycle is repeated. During the humidity cycle the Valve LED is lit while
the system is Cooling.
MEMORY
Fx-Maxx SDL Air Handler Control has nonvolatile memory which requires no batteries or any form of
backup power. When power is lost the operating parameters are retained indefinitely. When power is
restored, the control resumes operating as last programmed. All operating and programming parameters
are entered into nonvolatile memory instantly and are retained indefinitely.

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OPERATOR CONTROLS AND DISPLAY PANEL
Refer to figure 1 for the buttons locations and display functions listed on the following pages.
1. POWER BUTTON The power button is used to toggle between the on and off modes. Press the
power button once to toggle the unit to the on mode. Press the power button again to toggle to the
off mode.
2. FAN SPEED BUTTON The fan speed button is used to switch between Auto and Manual Fan
Speeds. Pressing and releasing the Fan Speed Button once toggles the fan mode as indicated by the
Fan LED indicator lamps. Press and release the fan speed button until the desired Automatic [A]
or Manual Fan Speed [1 through 6] is selected.
3. UP BUTTON Momentarily press the up button and the set point will appear in the temperature
display. Press and release the up button to increase the set point one degree. The set point is
increased by one degree each time the up button is pressed and released. The highest set point
allowed is 85 ° F. The up button is used with the down button to display the Water In temperature
when the control is on. The up button is also used to increase program values in the program mode.
4. DOWN BUTTON Momentarily press and release the down button to display the set point. Press
and release the down button to decrease the set point. The set point is decreased one degree each
time the down button is pressed and released. The lowest set point allowed is 55 ° Fahrenheit. The
down button is used in conjunction with the up button to display Water In temperature when the
control is on. The down button is also used to reduce program values in the program mode.

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5. MODE BUTTON The mode button is used to select one of the four operating modes. Press and
release the mode button and the Fx-Maxx SDL Air Handler Control will advance to the next mode.
Continue to press and release the Mode button until the desired operating mode is reached. The
mode selected is indicated by the Mode LED, i.e., Cool, Heat, Automatic or Moisture Mode.
6. TEMP SELECT BUTTON Press and release the Temp Mode Button to view inside air
temperature, outside air temperature or the set point. The appropriate LED, Inside, Outside or Set
Point will be lit indicating which temperature is being displayed. If no outside air sensor is installed
three [3] dashes will appear in the Three Digit Display.
7. THREE DIGIT SEVEN SEGMENT DISPLAY The inside air temperature is displayed in the
window whenever the control is turned on. The three digit 7 segment display provides a readout of
the inside air temperature.
The display also indicates program information, fault codes and outside air temperature when the
optional outside air sensor is installed.
The display momentarily indicates the set point when the up or down button is pressed.
When the control resumes operation after a power interruption all the display LEDs will turn on for
one second. This is a normal operating condition and is referred to as "Power On Reset".
8. HEAT MODE LED The heat mode LED will be lit when the Heat Mode has been selected. The
heat mode LED is also lit when the optional electric heat is installed and the heat mode is selected.
Electric heater status, on or off, is indicated by the right side decimal point [18].
9. COOL MODE LED The cool mode LED will be lit when the Cooling Mode has been selected
10. AUTO LED The auto LED is lit when the automatic heating or cooling mode has been selected.
The control will automatically switch to heating or cooling when this mode is selected.
11. MOISTURE CONTROL LED The moisture mode LED is lit when the Moisture Control has
been selected. This mode is used to control humidity during periods when the vessel is unoccupied.
12. MANUAL FAN LED The manual fan LED will be lit when one of six manual fan speeds has
been selected.
13. AUTO FAN LED The auto fan LED is illuminated when automatic fan speed operation has
been selected.
14. FAN SPEED BAR GRAPH There are six [6] individual fan speed LED's in the Fan Speed Bar
Graph. Each LED represents one [1] fan speed. Low fan speed [1] is indicated by illuminating the
first LED. High fan speed is indicated by illuminating all six [6] LED's. Any of the six [6] fan speeds
available are displayed by illuminating the appropriate LED's.
15. INSIDE LED The inside LED is lit when the inside air temperature is being displayed.
16. OUTSIDE LED The outside LED is turned on when the outside temperature is displayed.
17. SET POINT LED The set point LED is turned on when the set point is displayed.
18. VALVE LED The system operating status [Water Valve On or Off] is indicated by turning On
the right most decimal point in the 3 Digit Display.

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DUAL BUTTON FUNCTIONS
Up & Down Buttons Simultaneously Press the Up and Down buttons, while in the On Mode, to view
the chill water inlet temperature.
Simultaneously Press the UP & Down Buttons while in the program mode to set new custom
programming defaults.
MODES OF OPERATION
Off Mode
When the Fx-Maxx SDL Air Handler Control is in the off mode, all control outputs are turned off.
Program parameters and user settings are saved in nonvolatile memory. The program mode can only
be accessed from the off mode.
On Mode
When the control is in the on mode, power will be supplied to the appropriate control outputs and
the display will indicate the current state of operation. The operating and program parameters
resume based on those stored the last time the unit was operating.
Cool Only Mode
When Cool LED is on, only the cooling systems are selected and operated as required. When the
temperature drops below the set point, the system will not automatically switch to the heating
mode. Cooling only is available for customers that do not want automatic cooling and heating
operation.
Heating Only Mode
When the Heat LED is on, only the heating systems are selected and operated as required. Should
the temperature rise above the set point, the system will not automatically switch to the cooling
mode. Heating only is supplied for customers that require the system to not automatically switch
from the heating to the cooling mode.
Automatic Mode
When the Automatic LED is on, both heating and cooling are supplied as required. The heat and
cool LEDs will be lit according to the mode required. When the system requires the water valve to
be turned on for heating or cooling the water valve LED will turn on when the valve is on and will
turn off when the valve is off.
Temperature in a given mode will be maintained at two degrees Fahrenheit ( 2 ° F ), however, a four
degree difference is required to allow the control to change modes. Once in a new mode, the
temperature will remain within two degrees Fahrenheit ( 2 ° F ) of the set point.

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Moisture Mode
While in the on mode, press the Mode Button until the Moisture Mode LED is illuminated. The first cycle
will start in 1 minute. Every 4 hours, the fan is started and air circulated for 30 minutes. During this time
the air temperature is sampled and entered into memory. The cooling cycle is started and continues until
the temperature is lowered 2 ° F. The system is allowed a maximum of one hour running time to reach the
desired temperature. Four (4) hours after the temperature is satisfied or the one hour timer runs out the cycle
is repeated. During the humidity cycle the Water Valve LED is lit while the water valve is turned on and
the system is cooling.
FAN MODES
Automatic Fan Speeds
Fx-Maxx SDL has six automatic fan speeds available. Speed six is high, three is
medium and one is low or the slowest speed. Automatic fan mode allows the Fx-
Maxx SDL to determine the required fan speed based on 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 slower,
quieter fan speeds. Automatic fan operation is the factory default, however,
manual fan speed control is available.
Manual Fan Speeds
Six (6) is the fastest and one (1) represents the slowest fan speed. Manual fan
mode allows the user to select and maintain the desired fan speed manually. When
a manual fan speed has been selected, the fan speed bar graph will indicate the
speed selected by the number of LED's lit. Select speed 3, for example, and the
first 3 LEDs in the fan bar graph will turn on. Manual Fan Mode is sometimes
preferred when room temperature is constantly changing due to varying heat
loads.
PROGRAM MODE
Program Mode Overview
The program mode is used to adjust the systems operating
parameters to suit the particular needs of individual users. The
program mode is also used to tailor the air-conditioning system
for the most efficient operation within an installation. Installa-
tion variables such as, ducting, sensor location and system
layout effect the perceived operation of the overall system. The
program mode allows the system to operate as efficiently as
possible under all conditions. Fx-Maxx SDL Air Handler
Control is shipped with factory default settings which are
stored in permanent memory and can be recalled at any time.

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Warning
Severe electrical disturbances can sometimes upset the Fx-Maxx SDL operating sequences. Operator
confusion related to program parameters can also cause, what seem to be, operational problems.
Whenever there is any doubt as to the proper operation of the controller, Factory Default Parameters
should be Re-initialized.
ENTERING PROGRAM MODE
The program mode can only be entered from the Off Mode. From the Off Mode and in the
following order, press the Select, Up, Down and the Select buttons [ "SUDS" ]. These
buttons have to be pressed and released in the order given. The numerals "85" which represent
the high fan limit, appears in the display. The "85" is followed by the characters "P 1" followed
again by the parameter setting [ "85" ]. P 1 represents the first programmable parameter. The
Fx-Maxx SDL Air Handler Control is now in the program mode. Exit the program mode, to
the off mode, by pressing and releasing the power button.
NOTE: The control will exit the program mode and return to the Off Mode if no
programming is attempted for one (1) minute.
Restore Memorized Default Settings
IMPORTANT ! The memorized default settings can be restored by entering the program
mode and setting P-16 to rSt. Exit the program mode and the software version number
appears in the display. The memorized default settings are restored and the Fx-Maxx SDL
Air Handler Control returns to the off mode. The software version number is always
displayed when you exit the program mode.
USING THE PROGRAM MODE
Increment from one program parameter to the next by pressing the Mode Button while in the program
mode. Press and release the Mode Button to advance to the desired parameter. Use the up and down
buttons to change the program parameter values. The programmable parameters range from P-1
through P-18.
Up and Down Buttons
The up and down buttons are used to select the data or set the desired limits for the parameter being
programmed. This method is followed throughout the program mode, however, special instructions
are included for individual functions as require them.
Exiting the Program Mode
There are two methods to exit the program mode. Press the power button and the Fx-Maxx SDL Air
Handler Controlwill return to the off mode. Not pressing any buttons or attempting any program
changes for sixty (60) seconds will allow the control to exit the program mode to the off mode. Any
programming changes that were made while in the program mode will be memorized and put into
operation when the program mode is exited and the control is returned to the on mode.

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Programmable Parameters
There are eighteen (18) programmable parameter locations with their Factory Default Settings
listed in this section. The table below indicates what these parameters are, along with the permitted values
and the original Factory Default Settings.
Should any programming problems or confusion occur, reset the Memorized Default Settings by
entering the program mode and setting P-16 to rSt.
Program
Number
Description
Default
Range
P- 1 High Fan Speed Limit (arbitrary units) 85 56 - 85
P-2 Low Fan Speed Limit (arbitrary units) 50 30 - 55
P-3 Unused --- Reserved for future options N/A N/A
P-4 Temperature Sensor Calibration
Ambient Ambient ± 10° F
P-5 Unused --- Reserved for future options N/A N/A
P-6
Unused --- Reserved for future options N/A N/A
P-7
Unused --- Reserved for future options N/A N/A
P-8 Unused --- Reserved for future options N/A N/A
P- 9 Display Brightness Control
10
4 = Low
13 = Max imum
P- 10 Display ° Fahrenheit or ° Celsius °F °F = Fahrenheit Displayed
°C = C e lsius Disp layed
P-11
Outside Air Temp Sensor Only
When Alt Air Sensor in Not Required
OFF OFF =
Alt Air Available
On = OAT Sensor Only
P- 12 Reverse Fan Speeds During Heating Mode rEF = Reversed nor = Normal Fan Operation
rEF = Reversed Fan In Heating
P-13 Continous Fan or Cycle Fan with
Demand
con = Continuous
Fan Operation
CYC = Cycle
Fan On Deman d
con = Continuous Fan Operation
P-14 Chill Water Heating or Electric Heat no r = C hill Water
Heat Only
nor = C hill Water Heat Only
ELE = Electric Heater Installed
P-15 Fan motor type selection… Shaded pole
or split capacitor. SP = Shaded Pole SP = Shaded Pole Fan Motor
SC = Split Cap. Fan Motor
P-16 Reset
Memorized Programming Defaults nor = Normal rSt = Reset Defaults
P-17 Water Valve Forced Open 4 Hours to
Bleed the Chillwater System
nor = Normal
Operation
nor = Normal Operation
OPn = Valve Forced Open
P-18 Ambient Air to Chill Water
Temperature Differential 15°F 5°F to 25° Fahrenheit

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SPECIFICATIONS
SET POINT OPERATING RANGE .......................................................................................... 55 ° F TO 85 ° F
AMBIENT TEMPERATURE OPERATING RANGE DISPLAYED ..................................................... 55 ° F TO 85 ° F
SENSOR A CCURACY ......................................................................................................... ± 2 ° F AT 77 ° F
LOW VOLTAGE LIMIT 115 VOLT UNITS ........................................................................................... 75 VAC
LOW VOLTAGE LIMIT 220 VOLT UNITS ......................................................................................... 175 VAC
LOW VOLTAGE P ROCESSOR R ESET .................................................................................................. 65 VAC
LINE VOLTAGE ..................................................................................................... 115 THROUGH 230 VAC
FREQUENCY ............................................................................................................................ 50 OR 60 HZ
FAN OUTPUT ............................................................................................................ 6 AMPS @ 115 VAC
FAN OUTPUT ............................................................................................................ 6 AMPS @ 230 VAC
VALVE OUTPUT ..................................................................................................... 1/4 AMP @ 115 VAC
VALVE OUTPUT ..................................................................................................... 1/4 AMP @ 230 VAC
PUMP OUTPUT .......................................................................................................... 6 AMPS @ 115 VAC
PUMP OUTPUT .......................................................................................................... 6 AMPS @ 230 VAC
HEATER OUTPUT ......................................................................................................... 1 HP @ 115 VAC
HEATER OUTPUT ........................................................................................................... 2 HP @ 230 VAC
MINIMUM OPERATING TEMPERATURE ...................................................................................................0 ° F
MAXIMUM OPERATING TEMPERATURE ..............................................................................................180 ° F
MAXIMUM RHCONDITIONS ..................................................................................... 99 % NON CONDENSING
POWER CONSUMPTION ................................................................................................. LESS THAN 5 WATTS
DIMENSIONS
DISPLAY PANEL ............................................................................................................... 5.30" X 4.125"
PANEL CUT OUT .............................................................................................................. 4.20" X 3.375"
CABLE LENGTHS
DISPLAY ............................................................................................................................... 15' STANDARD
AIR SENSOR ......................................................................................................................... 7' STANDARD
WATER SENSOR .................................................................................................................... 7' STANDARD
SYSTEM INPUTS
1 ..................................................................................................... AMBIENT OR INSIDE AIR TEMPERATURE
1 ........................................................................................................WATER INLET TEMPERATURE SENSOR
1 ................................................................................ ALTERNATE AIR TEMPERATURE SENSOR [ OPTIONAL ]
NOTES: Maximum display cable length is 50 feet. Sensor cable lengths should also be limited to
50 feet. The water inlet sensor is plugged into the outside air sensor jack.

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WIRING DIAGRAM

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CONVECTOR APPLICATION

L-2337 Revision: 4-1-04
DometicCorporation
EnvironmentalSystems
2000 North Andrews Avenue Ext. • Pompano Beach • FL 33069-1497 USA
Phone: [phone] • Fax: [phone] • [e-mail] • www.marineair.com
Service Hot Line: 954-633-3150 • Service Fax: [phone]
Fleets Industrial Estate • 26 Willis Way • Poole, Dorset BH15 3SU, England
Phone: [phone] • Facsimile: [phone]