ARP Fridge Defend User manual

Fridge Defend® by ARP
v5.x ARP & ARP + Fan Control
User Guide
Please click here for Online ARP Video Operation Manual
User Web Search Engine:
Click Here for Web Search before Contacting ARP Control
WARNING: The operator of the ARP Control is responsible for knowing the status of the
control at all times, including the self-test functions. The ARP Control is designed to turn itself
on if a power interruption occurs. A power interruption can be as simple as using the RV
Master Power Switch to turn off power during storage of the RV. In this situation, when the
power is restored to the RV, the ARP Control will turn itself on incase the operator forgets to
check the control. The operator must perform the Test of ARP Relay described in this manual
before each outing to confirm function of the ARP Control. Also, brown outs and transient on
the RV 12VDC supply can turn off the ARP Control, these power interruption are due to many
factors which go beyond the scope of this document to describe. Due to brown outs and
transients one needs to confirm that the ARP is functioning on a regular basis.
©2020 ARPC L.L.C. All rights reserved.

Terms -- Conditions & Contact Information
TABLE of CONTENTS
This manual is copyrighted © by ARPC L.L.C. 2013-2020. All rights are reserved. This manual may only be reproduced
with permission of ARPC L.L.C.. This manual is furnished for informational use only and is subject to change without
notice. This manual does not imply any commitment on the part of ARPC L.L.C. or its business partners. ARPC L.L.C.
and its business partners assume no responsibility or liability for any error or inaccuracies that may appear in this manual.
By use of this document for installation and operation of the ARP Control (Fridge Defend®), the user is agreeing to the
ARPC L.L.C. terms and conditions found in document ARPC LLC License Agreement.pdf. Also, the end user needs to
understand that the ARP Control can be turned off at any time, thereby removing the ARP Control function and reverting
to the operation of the refrigerator to its previous state. Also, the self-test functions which make the Fridge Defend an
accessory safety control may be turned off by the end user; this will defeat the 24 hour self-test. Power surges can turn off
the ARP Control just the same as any equipment in an RV, thus it is the operators responsibility to insure that the control
is functioning properly. Any ARP Control that is believed to be malfunctioning, the ARP Control must be removed from
operation and returned to ARPC L.L.C. for inspection immediately. Contact ARPC L.L.C. for shipping instructions. The
reason for return must be included in writing with the returned control; shipping is the responsibility of the end user to
and from ARPC L.L.C..
The document "ARPC LLC License Agreement.pdf" can be downloaded at web address
http://www.ARPrv.com
or, please send any request to e-mail address below, ARPC L.L.C. will supply information in a timely manner:
[email protected]
GRAPHICAL REFERENCE .....................................................................................................................1
INTRODUCTION ......................................................................................................................................2
IEC TYPE ACCESSORY SAFETY CONTROL........................................................................................2
FAN CONTROL & NON-FAN CONTROL................................................................................................2
BUTTON FUNCTION ...............................................................................................................................2
ARP FUNCTION.......................................................................................................................................1
1.1 Turn on ARP Control ...............................................................................................................1
1.2 View Boiler Temperature.........................................................................................................1
1.3 View Fan Temperature.............................................................................................................2
1.4 View Fridge Voltage.................................................................................................................2
1.5 Test ARP Relay.........................................................................................................................2
1.6 Test Fan Relay..........................................................................................................................2
1.7 Controller Function Test .........................................................................................................3
1.8 ARP Protection Period (What are the numbers on the display?)........................................3
1.9 Rapidly Flashing *O*F*8..........................................................................................................3
1.10 Excessive Overheat Condition *H*O*8.................................................................................4
1.11 Turn off ARP Control.............................................................................................................4
1.12 Restore Factory Control........................................................................................................4
MODE FUNCTIONS.................................................................................................................................4
2.1 ARP Control Mode ...................................................................................................................4
2.2 No Set-Point Mode...................................................................................................................5
2.3 Auto Tune Mode.......................................................................................................................5
2.4 SetUp Mode ..............................................................................................................................5
CONCLUSION..........................................................................................................................................5
©2020 ARPC L.L.C. All rights reserved.

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 1
GRAPHICAL REFERENCE
Download Detailed Graphical Info: Ancillary_Graphical_User_Instructions_v4.x.pdf
1: ON/OFF BUTTON
General Install Guide
1.6 ARP Control and your Refrigerator
ARP User Guide
BUTTON FUNCTION – Use this section to understand how to make changes
with the buttons.
1.1 Turn on ARP Control
1.11 Turn off ARP Control
1.12 Restore Factory Control
MODE FUNCTIONS – The ARP must be turned off to enter any of the
startup modes.
2.1 ARP Control Mode – See 2 & 3 below for other startup modes.
2: DISPLAY BUTTON
ARP User Guide
1.2 View Boiler Temperature
1.3 View Fan Temperature
2.2 No Set-Point Mode
3: SETUP BUTTON
General Install Guide
12.1 Testing ARP Install
ARP User Guide
1.5 Test ARP Relay
1.6 Test Fan Relay
1.7 Automated Test
2.3 Auto Tune Mode – This mode is very rarely used.
2.4 Setup Mode
Troubleshooting Guide
SETUP MODE – Be sure to store new settings before exiting SetUp Mode.
2.2 Types of SetUp Mode Variables
4: DISPLAY
ARP User Guide
1.8 ARP Protection Period
1.9 If *O*F*8 is Displayed – 5 Time Trigger Event
1.10 If *H*O*8 is Displayed – Excessive Overheat Condition
Troubleshooting Guide
ARP ERROR MESSAGES

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 2
INTRODUCTION
To control digital equipment such as cell phones, there is a sequence of button selections and
resulting information displayed. The Fridge Defend is no different, thus, as with all digital
equipment a user guide is necessary for proper setup and operation.
The following user guide gives a brief graphical description of how to operate the ARP Control.
This document shall be considered as a cheat sheet because only a brief description of each
function is given. This is not an inclusive operator's manual. The operator of the ARP Control
shall understand all information provided in this guide in addition to the Installation Guide and
the Troubleshooting Guide. Please see aforesaid guides for important safety information.
IEC TYPE ACCESSORY SAFETY CONTROL
Dometic and Norcold absorption refrigerators are driven by a fired boiler. It is considered good
engineering practice to monitor fired boilers for thermal run away conditions with a safety
controller. The patented Fridge Defend is an accessory IEC type safety controller that uses
standards, including applicable ( and practical ) IEC 60730 automatic electrical control checks,
combined with functional self-tests to provide an economical, yet functional, safety control.
__________________________________________________________________________________________
FAN CONTROL & NON-FAN CONTROL
This user manual covers two types of control as follows:
ARP v5.0 is the basic version without fan set-point control. The cooling unit boiler protection
operates the same as all previous controls.
ARP v5.1 is the same as the basic version with the addition of fan set-point control. This
version of control has added function of turning on/off one or more 12VDC fans to help the
cooling unit move heat away from the fridge and defrost/circulate air within fridge.
__________________________________________________________________________________________
BUTTON FUNCTION
The following terms are used in the text to indicate how to make changes to the ARP control
using the push buttons:
Momentarily Press: This indicates that the operator depresses the button and then
immediately releases in order to make a change.
Press and Hold: This indicates that the operator holds the button until a change occurs, once
the change takes effect, release the button.

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 1
ARP FUNCTION
1.1 Turn on ARP Control
Momentarily press the On/Off button to start the control
in the ARP mode.
A display check is preformed by turning on all
segments of the LED. Following the display will show
ArP for 3 seconds. If there are any errors detected
during startup, these errors will be displayed at this
time. If no errors are displayed, the control immediately
enters the ARP mode.
Note: Every time the ARP has 12VDC applied to the
red wire, the control will turn on.
In ARP mode, fan control is active for the v5.1 control.
The ARP control will turn on/off the fan when the fan
temperature sensor reaches the fan set-point. Please
see the Troubleshooting Guide, Ancillary Graphical,
or online Video Operation Manual to change fan control
temperature.
If the left dot flashes on startup, you have a control that
is made previous to the v4.x, this guide does not apply.
If an error was detected that prevents the ARP from
functioning, an error message will be displayed.
Please see Troubleshooting Guide for expiation of
displayed errors.
If no errors are detected during startup, the center dot
will flash every 4 seconds on the v5.xand newer. The
center dot must be flashing when in the ARP control
mode for the controller to protect your refrigerator. It is
a good idea to check to make sure the center dot is
flashing to insure protection.
1.2 View Boiler Temperature
Press and hold the center Display button till the
present boiler temperature is displayed and then
release the button. This may take 2 seconds. The
boiler temperature will display every other second till
you press and hold the Display button again. If you
have the v5.0 control, jump ahead to section 1.4. For
the v5.1 control, see next section.

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 2
1.3 View Fan Temperature
If the control is a v5.1 control, after viewing the boiler
temperature, press and hold the center Display button
to view the fan sensor temperature.
The fan temperature is only displayed in °F. The fan
sensor temperature will display every other second.
Press and hold the center Display button again to read
the fridge voltage.
The fan sensor measures in the range of 35°F & 155°F.
The display will show OR (Out of Range) if not within
the above temperature range. See Troubleshooting
Guide for fan on/off temperature settings.
1.4 View Fridge Voltage
The voltage on the yellow ARP wire is displayed. This
example shows 13.7 volts supplied to the fridge by the
ARP. The fridge voltage is an extremely useful
troubleshooting parameter. Please see the
Troubleshooting Guide for more info using this
parameter.
Press and hold the center Display button again, the
display will return to flashing the center dot.
1.5 Test ARP Relay
The next 3 modes of operation will override all ARP
functions. Make sure to return the ARP Control to the
desired mode of operation when tests are completed.
Press and hold the SetUp button to test the ARP relay.
Your fridge must shut off during this test. The display
will flash OFF every other second until the SetUp
button is held down again to go to the next test.
This test should be preformed in both the gas and
electric modes to confirm that the ARP will turn off the
refrigerator for protection.
1.6 Test Fan Relay
Hold the SetUp button again to test the fan relay if you
have a v5.1 control. Your fan should turn on; also your
fridge will be turned back on from the previous test.
The display will flash FAn every other second.
Hold the SetUp button again to turn off the fan and
proceed to the automated control function test.

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 3
1.7 Controller Function Test
This is an automated test, when tSt is displayed the
test is being preformed. To meet IEC Design standards,
the v5.1 control has an alarm that alerts the operator
that there is a critical system failure, the alarm will
sound during this test (v5.0 omits this function for
economy). The operator must hear the audible alarm
during this test for the v5.1. When the test finishes, one
of two events will occur:
If the test passes, PAS will display, use the SetUp
button to exit the test. The center dot will resume
flashing to indicate that the control is returned to the
ARP Control mode.
If either the F4 or F5 error message is displayed,
contact ARP & discontinue use of controller.
On/Off Display SetUp
1.8 ARP Protection Period (What are the
numbers on the display?)
When the ARP Control detects an overheat situation,
the control turns off the refrigerator and starts a
countdown period. The countdown period is the time
until the ARP attempts a safe restart of the refrigerator.
WARNING: Please do not turn off the ARP
Control during this protection period. Allow the Fridge
Defend to do its job, otherwise damage may occur.
On/Off Display SetUp
One of three events will occur at the end of the
countdown period:
1) If the boiler has cooled enough, the control will
restart the refrigerator & center dot will resume flashing.
2) If the temperature is still too high to restart the fridge,
000 will flash until it is safe to restart the fridge.
1.9 Rapidly Flashing *O*F*8
If the control turns off the refrigerator 5 times in a row,
the ARP will turn off the refrigerator and rapidly flash
*O*F*8 until the operator resets the control by turning
off the ARP. For the v5.1 control, an audible alarm will
sound alerting the operator that the fridge has an error.
Please consult an RV repair facility to restart your
fridge if this event occurs. Please see next 2 sections
and Troubleshooting Guide for further details.

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 4
1.10 Excessive Overheat Condition *H*O*8
If the control turns off the refrigerator 5 times in a row,
and your boiler temperature has reached 250°C
(482°F), the ARP will turn off the refrigerator and
rapidly flash *H*O*8 until the operator resets the control
by turning off the ARP. For the v5.1 control, an audible
alarm will sound alerting the operator that the fridge
has an error. Please consult an RV repair facility to
restart your fridge if this event occurs. Please see next
section and Troubleshooting Guide for further details.
1.11 Turn off ARP Control
The ARP Control can be turned off by pressing and
holding the On/Off button. The display will show the
following characters in sequence.
After OFF is displayed, and the display goes blank, the
ARP Control is turned off. The process takes about 3
seconds.
DANGER: This action returns the control of the
fridge to the factory safety devices. This action
effectively bypasses or removes the Fridge Defend
safety control for troubleshooting and testing of the
fridge.
On/Off Display SetUp
1.12 Restore Factory Control
When the ARP Control is turned off, there is no
information on the display, and your fridge functions as
it came from the factory.
This feature was implemented due to customer
request. The operator of the ARP has full discretion to
control their fridge. Seek professional help from a
qualified RV repair person if in doubt.
MODE FUNCTIONS
The ARP Control has 3 modes of operation that are initiated upon startup of the control.
Restated, turn off the ARP Control (see 1.10) before attempting to enter into different startup
mode functions. The following discussion assumes the control has been turned off, and the
operator has waited 4 seconds before restarting the control in the desired mode.
2.1 ARP Control Mode
Activation of the ARP Control mode is described above, see 1.1 Turn on ARP Control.

ARP Control v5.x User Manual 04/20/2020 ©ARPC L.L.C. All rights reserved. 5
On/Off Display SetUp
2.2 No Set-Point Mode
Press and hold the center Display button while
momentarily pressing the On/Off button. Wait until SP0
is displayed to release the Display button. The left and
center dot will flash to tell the operator that the control
is in the SP0 mode.
This mode is for diagnostics only, the ARP Control will
not turn off the fridge if the boiler over heats when in
the SP0 startup mode. This mode is for advanced
users only! Please see the Troubleshooting Guide for
further information.
On/Off Display SetUp
2.3 Auto Tune Mode
Auto Tune is only necessary if the standard 3 ARP
Control settings do not work. 98% of fridges will
work with the standard settings: C-H, PID, C-L control
modes. Please read the Auto Tune section of the
Troubleshooting Guide before running Auto Tune!
To start Auto Tune, hold down both the right SetUp
and the center Display buttons. Then momentarily
press the On/Off button. Wait until At is displayed to
release the Display and SetUp buttons.
2.4 SetUp Mode
Hold down the right SetUp button and then
momentarily press the On/Off button, when AtO
displays, release the SetUp button.
AtO and its value will alternatively display.
Please see both the Troubleshooting Guide &
Ancillary Graphical User Instructions for further
information concerning the Setup Mode functions and
adjustment for both ARP and the optional fan control.
CONCLUSION
The ARP Control will protect your fridge by limiting the boiler temperature. The control has a
number of functions that allow the operator to test the operation of the control. Please see the
Installation Guide, Troubleshooting Guide, &Ancillary Graphical User Instructions for
further information on how to install and setup the control if the default programming does not
work for your installation. Further modes of operation are defined in the aforesaid documents.
Please check for updated documents online.

This manual has been provided courtesy of
My RV Works, Inc.
www.myrvworks.com
You can find more RV service manuals here:
www.myrvworks.com/manuals
Over the years of running a mobile RV repair service, having a dedicated place
to access service manuals for all the different appliances and components
found on RVs was something that I always had a desire to create.
I hope this resource makes your RV repairs easier, as it has mine, but please
be careful and follow proper safety practices when attempting to repair
your own RV.
If in doubt, please consult with a professional RV technician!
All service manuals provided on www.myrvworks.com are believed to be
released for distribution and/or in the public domain.
DARREN KOEPP - OWNER, MY RV WORKS, INC.