WITHOUT FRIDGE DEFEND YOU ARE NOT PROTECTED
Dometic & Norcold reliability and fire safety, can you live without it?
WITHOUT FRIDGE DEFEND YOU ARE NOT PROTECTED
Dometic & Norcold reliability and fire safety, can you live without it?
Your Dometic fridge does not come from the factory with adequate boiler temperature protection. This page shows the different Dometic wiring schemes along with the recalls enabling one to determine how to wire the Fridge Defend Control.
Around the year 2000 Dometic refrigerators started developing problems that resulted in fridge failure. The majority of these failures were located in the cooling unit boiler area. As as a result, recalls of the refrigerators were mandated. One fact is evident, the recalls were not totally effective because the failures continued. The Fridge Defend addresses one of the root causes of RV fridge failure which can result in a fire, the cooling unit boiler overheating. The Fridge Defend limits the cooling unit boiler temperature when installed, maintained, and operated correctly. To view how the boiler maintains a constant temperature, or overheats, click here to view video.
The following Dometic wiring schemes are provided so that the installer can easily identify the factory wiring scheme. Each wiring scheme is numbered for ease of communication if telephone or e-mail installation assistance is needed.
REQUIRED TO DOWNLOAD INSTALLATION INSTRUCTIONS - WEB PAGES ARE SUPPLEMENTAL - EACH VERSION OF CONTROL HAS INTRICACIES REQUIRING THE WRITTEN INSTRUCTIONS.
Instructions: Some of the models of Dometic fridge are listed on the left, not all. Please scan the wiring schemes, if your fridge is not listed please use the Contact Us form. Click the link to the right to go directly to the wiring drawing for your fridge model.
On some models of Dometic fridge, the fridge can be either a 2-way or a 3-way model, the fridge
model number does not inform the installer which model it is at times,
as a rule of thumb, if the last number is a 3 in the model number, it is
a 3-way fridge.
Please use the image of the Dometic eyebrow boards to determine if your fridge is a 2-way or 3-way model.
Next, select the appropriate wiring scheme below for your type of fridge.
Please note that the image to the right, 'D' is the DC LED, this makes this model a 3-way fridge.
The image to the right also has a DC mode selection button (2), where as the 2-way fridge does not have this button.
This symbol indicates a dashed wire and a circle with cross-out:
• The dashed line/wire is how the fridge was originally wired.
• The circle with cross-out indicates to remove the wire and replace with the shown
Fridge Defend by ARP wiring.
(1) Starting at the RV, the RV delivers power to run the fridge and its controls. Please note that two wires will enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. The ARP must be wired in-line with the +12VDC going from the screw terminal into the Dometic control box. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal (2) on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source coming from the RV battery. Remove the positive lead from the screw terminal and connect it to the ARP red wire. The ARP yellow wire is connected to the screw terminal where the power wire was removed in the last step.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
(5) This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is behind the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Right-Hand ARP Sensor Install Video
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Please look at the difference between this early version of the Domenic control scheme and the late version just below. The difference is the way that the boiler thermal switch is wired, the +12VDC power to the fridge comes through the boiler thermal switch for this drawing.
(1) Starting at the RV, the RV delivers power to run the fridge and its controls. Please note that two wires will enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. The ARP must be wired in-line with the +12VDC going from the screw terminal into the Dometic control box. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal (2) on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source, the screw terminal positive. Remove the positive lead from the screw terminal and connect it to the ARP red wire. The ARP yellow wire is connected to the screw terminal where the power wire was removed in the last step.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
(5) This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is behind the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Right-Hand ARP Sensor Install Video
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Please look at the difference between this late version of the Domenic control scheme and the early version just above. The difference is the way that the boiler thermal switch is wired, this drawing the boiler thermal switch is wired directly to the control box. The +12VDC is run directly to the Dometic controller for this drawing.
(1) Starting at the RV, the RV delivers power to run the fridge and its controls. Please note that two wires will enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. The ARP must be wired in-line with the +12VDC going from the screw terminal into the Dometic control box. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal (2) on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source coming from the RV battery. Remove the positive lead from the screw terminal and connect it to the ARP red wire. The ARP yellow wire is connected to the screw terminal where the power wire was removed in the last step.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
(5) This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is behind the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Right-Hand ARP Sensor Install Video
Please click here to see an alternative to this method.
We would like to begin by stating that we never use our 3-Way, where the 3rd way is the 12VDC heater. The 12VDC heater is not very effective for keeping the fridge cool, and without the ARP Control on the fridge use of the 12VDC heater is a great way to burn up the fridge. Therefore, one may just disconnect the 12VDC heater and wire your ARP Control the same as seen in the 2-way drawings.
In order to use the ARP Control with the Dometic 3-way fridge, where 3-way means the fridge can be run off of 12VDC heater, a relay for supplying power to the 12VDC heater is needed on some fridges.
(1) All fridges have two wires delivering the 12VDC power supply from the RV. When there is a 12VDC heater on the fridge, the wiring must be as shown using a relay (4) to power the 12VDC heating element. Note that the +12VDC power supply coming from the RV (1) to the fridge has to split, one line powering the ARP and the other supplies power to terminal 30 of relay (4).
(2) The ARP Control would be wired according to the installation instructions with the exception that the red 12VDC power wire would branch before the ARP Control so that relay (4) would handle the power load required by the 12VDC heater.
(3) Number 3 represents the factory Dometic controller. From the factory the 12VDC heater (5) may be wired directly to controller number 3.
(4)
The load relay shall be wired as follows:
Terminal 30: The power supply entering the
cooling unit compartment will power this terminal, make sure
adequate fusing is on the RV.
Terminal 85: The relay coil will be grounded
through this terminal.
Terminal 86: Preform the next step,
terminal 87 before this step. Once terminal 87 is wired, run a wire
from where you removed the +12VDC electric heater wire on the
factory control (3) to terminal 86 on the relay. This wire will
activate the relay coil and in turn supply power to the 12VDC heater
(5).
Terminal 87: Locate the +12VDC power wire
from the electric heater (5) to the factory control (3), remove it
from the factory control (3) and place this wire on the relay
terminal 87.
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(1) Starting at the RV, the RV delivers power to run the fridge and its controls. Please note that two wires will enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. The ARP will interrupt the power to the RV fridge in order to turn on and off the cooling unit heat source. The ARP must be wired in-line with the +12VDC (smaller red wire) going from the screw terminal into the Dometic control box. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal (2) on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source, the screw terminal positive. The ARP yellow wire is connected to the red wire that supplies power to the Dometic control box.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
(5) This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is behind the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Right-Hand ARP Sensor Install Video
(6) This shows the Dometic 12VDC electric heater relay. All of the wiring that is not necessary for the install of the ARP is not shown in this diagram.
(1) Starting at the RV, the RV delivers power to run the fridge and its controls. Please note that two wires will enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
TERMINAL BLOCK All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. Some Dometic fridge have a 3-wire terminal block with connections identified as follows: (+): +12VDC coming from battery. (-): Ground Connection (GND) D+: Engine Alternator Signal (Activate Door Locks) The ARP must be wired in-line with the +12VDC going from the battery to the screw terminal on the side of the screw terminal that has just one wire. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal (2) on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source coming from the RV battery. Remove the positive lead from the screw terminal and connect it to the ARP red wire. The ARP yellow wire is connected to the screw terminal where the power wire was removed in the last step.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
Dometic Left Hand Boiler This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is in front of the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Left-Hand ARP Sensor Install Video
(6) Note that there are two wires coming out of the one side of the Terminal Block, one wire goes to the Boiler Housing Thermal Switch, and the other goes to relay (6). Do not wire the ARP to only one of these wires, the fridge will not restart properly, this will show up during the post ARP install.
This drawing applies to 1.x, 2.x, & 4.x ARP Controls, see below for v3.x. The difference between this relay drawing and the v.3x below is the position of the relay 87 and 87a wires.
All of the same principles apply to these drawings as above, please use the text in the drawings above for guidance.
Please note that the Relay 87a Buzzer or Alarm is an option which is not necessary unless the end user desires this function.
See drawing directly below for the correct relay part number (P/N).
The 3.x control has an added feature, the logic of the ARP Control can be inverted. Download the Troubleshooting_Guide_v3.x.pdf, go to page 15, section 9.4 to set the Output Mode for the necessary logic setting for this figure that uses the relay 87a Power To Fridge terminal (as opposed to above figure that uses the relay 87 terminal).
The difference between the ARP 1.x or 2.x control and the 3.x is the wiring of relay terminals 87
and 87a.
The Norcold Thermocouple Interrupt adapter controls the LP Gas flame. If the ARP senses a boiler
overheat situation, the ARP relay breaks the signal to the gas safety valve.
Please use this drawing along with the drawings above to wire your ARP Control.
The difference between the ARP 1.x or 2.x control and the 3.x is the wiring of relay terminals 87
and 87a.
The Norcold Thermocouple Interrupt adapter controls the LP Gas flame. If the ARP senses a boiler
overheat situation, the ARP relay breaks the signal to the gas safety valve.
Please use this drawing along with the other Dometic drawings on this page to wire your ARP Control.
In addition, see the Control Logic Setting section in the Troubleshooting Guide to toggle the v3.x control
to the proper control logic for this wiring scheme.
This drawing shows the typical Dometic manual control assembly. Please take note to item (7), this is the 'gas safety valve'. (7) points to the screw connection between the 'flame sensor' (thermocouple) and the actual 'safety valve' that is underneath the identifier (10). Unscrew the thermocouple from the safety valve and insert the 'Thermocouple Interrupt' (Norcold P/N: 621737) and wire according to the drawings above.
This photo shows the late style Dometic control found on the RM2352, RM2353, RM2452, 2453, RM2552, and RM2553 to mention a few. Please note that the thermocouple comes to the top of the fridge, it screws into the back of the gas lighting pushbutton. The thermocouple interrupt adapter is seen wired to the ARP Control relay.
(1) Starting at the RV, the RV delivers power to run the fridge and the NDR1292 or NDR1492 controls. 1492 Note: See next wiring scheme for NDR 1492 without thermal sensor. Find the two wires that enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. Some Dometic fridge have a 3-wire terminal block with connections identified as follows: (+): +12VDC coming from battery. (-): Ground Connection (GND) D+: Engine Alternator Signal (Activate Door Locks) The ARP must be wired in-line with the +12VDC going from the battery to the screw terminal. This drawing does not show the 3rd terminal, if you have the 3-terminal block, please see the RM1350 drawing. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source coming from the RV battery. Remove the positive lead from the screw terminal and connect it to the ARP red wire. The ARP yellow wire is connected to the screw terminal where the power wire was removed in the last step.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
Dometic Left Hand Boiler This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is in front of the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Left-Hand ARP Sensor Install Video
(1) Starting at the RV, the RV delivers power to run the fridge and the RM7030, RM7132, or other 7000 series or controls. RM1492 Note: Please see above wiring scheme for NDR 1492 with thermal sensor. Find the two wires that enter the cooling unit compartment, one power and the other ground. Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) All Dometic fridge have a screw terminal where the power and ground wires are routed from the RV battery to the fridge control. Some Dometic fridge have a 3-wire terminal block with connections identified as follows: (+): +12VDC coming from battery. (-): Ground Connection (GND) D+: Engine Alternator Signal (Activate Door Locks) The ARP must be wired in-line with the +12VDC going from the battery to the screw terminal. This drawing does not show the 3rd terminal, if you have the 3-terminal block, please see the RM1350 drawing. Click for Further Reading on ARP Function
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug next to the screw terminal on the sheet metal plate that the control box is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source coming from the RV battery. Remove the positive lead from the screw terminal and connect it to the ARP red wire. The ARP yellow wire is connected to the screw terminal where the power wire was removed in the last step.
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
(5) This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is in front of the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Left-Hand ARP Sensor Install Video
(1) Starting at the RV, the RV delivers power to run the fridge and its controls. Please note that two wires will enter the cooling unit compartment, one power and the other ground, these wires go to the terminal block (2). Because the color of the power wires vary by RV manufacture it is up to the installer to determine the correct wire color for the power and ground.
(2) The ARP will interrupt the power to the RV fridge in order to turn on and off the cooling unit heat source. The ARP must be wired in-line with the +12VDC (smaller violet wire) going from the screw terminal (upper figure) or the thermal switch (lower figure), which goes to the Dometic control box (4). Click for Further Reading on ARP Function
The terminals are identified as follows:
(1) Negative/Ground 12 Volt connector for electronics (black wire).
(2) Positive 12 Volt connector for electronics (violet wire).
(3) D+ alternator signal - optional (black wire).
(4) S+ solar panel signal - optional (white wire).
(5) -12VDC heater (white wire).
(6) +12VDC heater - 16A fused (red wire).
(3) Always start wiring by disconnecting the power to the fridge, this can be done by removing the fuse. The next step is to connect the ARP ground. The ARP ground is the green wire, the green wire may be connected either to the screw terminal, or the ground lug on the sheet metal plate that the igniter is mounted on. The ARP is shown spliced into the power wire, where the ARP red wire is connected to the power source, the screw terminal positive. The ARP yellow wire is connected to the violet wire that supplies power to the Dometic control box (eyebrow board).
(4) This is the Dometic control box, see (3) for wiring. Also, it is a good idea to either use an in-line fuse or an ARP Circuit Breaker in-line with the power supply to the control box.
(5) This is a simplified drawing of the tubes inside the boiler housing. Please note that the boiler tube (black) is behind the flue tube (red). The ARP Boiler Sensor is clipped onto the boiler tube (black), orient the clip so that it snaps around the back of the tube. Move the sensor away from the flue tube (red) and pack fiberglass insulation between the flue tube and the ARP Boiler sensor. Use caution routing the wires out of the boiler housing, the wires must not be cut by the boiler housing sheet metal, wrap fiberglass insulation around the Boiler Sensor wires to protect them. Click to see the Dometic Right-Hand ARP Sensor Install Video