Norcold 2118 | PolarMax | Service Manual Specifications

If you do not have the ARP Control you are not protected. This page shows how to install the ARP Control and gives service manual specifications for troubleshooting and repair of Norcold 2118 PolarMax fridges.

This page is intended to supplement the installation documentation and is not considered to be complete.

Table of Contents


Instructions: Subjects are listed on left. Click the link to the right to go directly to the subject matter on this page.

Norcold 2118 Cooling Unit

Norcold 2118 Cooling Unit Compartment

The first photo is of the ARP Control installed on a 2118 PolarMax in a Montana 5th Wheel trailer. Please note that the Norcold 2118 cooling unit compartment has plenty of room for mounting the ARP. It is desirable to mount the control on the metal plate as seen in this photo. Velcro Industrial tape was used to attach the ARP to the metal plate. The screws that come with the ARP can be use also.

The next photo is a close-up of the 2118 refrigeration controller. The +12VDC power and ground are identified. The wiring procedure is straight forward for this control. The +12VDC power wire will be removed from the Norcold control and connected to the ARP red wire. The ARP should be grounded at the Norcold control ground wire.

Please view the drawing below for the following step by step instructions:

Norcold 2118 Controller

Norcold 2118 - Wiring ARP

The following two photos show how to wire the ARP. The second photo on this page shows the RV power supply wires entering into the cooling unit compartment and going to the Norcold control. The drawing after shows how the ARP will appear after fully wired.

(1) On this RV, the ground wire is white and the +12VDC wire is white with a red stripe. The colors of the wires on your RV are dependent on the manufacture. The first step is to identify the correct wires delivering power to the fridge.

(2) This is the Norcold recall, please see this page for more information on the function of this recall: Norcold Recall Function

2118 Wiring

(3) This shows how the power coming from the RV goes to the ARP red wire, and the ARP yellow wire being connected at the location on the Norcold control where the RV +12VDC was disconnected.

(4) Norcold control box as seen in second photo on this page, with the exception that the power is now coming from the ARP control.

(5) To make the wiring complete the ARP boiler temperature sensor is shown within the boiler housing on the boiler tube. Please see the next section for the installation of the boiler sensor.

2118 Wiring

Norcold 2118 - ARP Boiler Sensor

This photo is of a Norcold 2118 boiler tube with the ARP temperature sensor being clipped on. The sensor needs to be approximately an inch above the heating elements at minimum. The sensor should not be higher than the second from top absorber coil, which is very hard to reach if the fridge is installed in the RV.

Once the ARP sensor is installed correctly, please see installation instructions, the sensor should be insulated with fiberglass insulation so that it only reads the boiler tube temperature.

Often the boiler needs to be insulated where the gap in the factory insulation is. If this gap is open, cool air will enter the boiler housing and reduce the efficiency of your fridge.

Fault / Error Codes 2118 Series

No Display No 12VDC to Fridge. Make sure fridge is on.
Check power and ground at Norcold Control board.
ARP Control detected an overheat situation, check ARP display to see if a count down period tells when control will turn back on fridge.
Check under control board cover Fuse F1.
Check Norcold recall, if LED on, click here for reset.
no AC The shore power is less than 85VAC. This fault only occurs while operating in the AC Mode. If in Auto Mode this code is displayed with other codes such as flashing 'no FL'. Check power cord for shore power and at fridge.
Click here for AC safety and GFI receptacle.
Fuse F2 under Norcold control box cover blown, click here for fuse type.
no FL LP flame did not light. This fault is only present when in the Gas Mode. This fault will be presented with other faults if in the Auto Mode. Remove LP burner cover, check electrode gap, clean burner, check wiring and ground for LP igniter.
Click here for igniter adjustment. Turn off fridge and restart.
Check LP Gas pressure and electrode gap.
Click here for gas valve and igniter check.
FL -- LP flame on when there should not be. This can be from either a stuck open gas (SOV) valve, or the relay in the controller stuck shut and power is activating the SOV.
no AC

no FL
Two faults occurred: The controller sensed the AC input voltage to be less than 85VAC. When above condition was sensed, the controller switched to LP Gas Mode and a flame was not sensed. Please see the combined above faults and use the information there for solutions.
AC HE AC Heater current low. AC heaters failed.
Click here for improved AC heater safety.
Click here for AC heater troubleshooting.
AC rE AC heater relay is stuck closed. Try cycling the fridge on/off. Open cover for power board and tap on AC relay to see if can free up.
oP LI Norcold recall has tripped, caution needs to be exercised. This code requires caution due to the nature of the Norcold recall black box. These black box can false trip, or if they do trip due to overheat, there is a dangerous situation that may need to be addressed.
Click here to understand the need for the ARP Control & why 800F is just too hot for black box trip point.
Click here for reset procedure and testing of cooling unit.
Click to see Norcold 1200 series recall for further info.

Norcold 2118 PolarMax Specification Table

Please note that all of the following specifications are believed to be accurate. If any errors are found, please bring them to our attention as soon as possible. For critical specification please contact Norcold as they make changes to their specifications without notice.

Item Value Units
ARP Control Boiler Temperature See Note 1 Below
2118 Total Volume 18 cu. ft
2118 Freezer Volume 5.9 cu. ft
Off-Level Operating Limit See Note 2 Below
Temp Setting Range 1 - 9 9 = Coldest | See Note 3 Below


Item Value Units
Board 12V Fuse 5A Amp
120VAC See Note 4 Below Amp

DC Power

Item Value Units
Divider, Flaper, Perimeter Heaters 0.967 Amp
Interior Light 0.5 Amp
Gas Valve 0.146 Amp
Ice Maker Heaters 1.875 Amp
Fans 1 Amp
Total Amp Draw 4.342 Amp

AC Power

Item Value Units
Operating Range 108 - 132 VAC
AC Heaters 300 / 2.5 Watts / Amps (per heater)
AC Heaters 46 - 51 Ohms (per heater)
Measurement Conditions 120 VAC

LP Gas

Item Value Units
Gas Pressure 10.5 - 11.5 inch w.c.
Heat Input 3000 BTU/hour
Gas Jet LP22
Burner 8-slot
Electrode to Burner Gap 1/8" to 3/16" inch

2118 NOTES

Note 1: 185-195°C - 365-383°F

Note 2: Dependent on ambient and ARP boiler temp.

Note 3: Also see thermistor location, second fin from right at this link: Thermistor Troubleshooting
If the thermistor has failed, put the fridge control onto the fridge temperature display mode.
If the display flashes, the thermistor may have a bad connection or need to be replaced. Please see thermistor tables below.

Note 4: AGC Series, 8A, Fast Acting.

Norcold 2118 PolarMax Thermistor Table

Temperature (F) Temperature (C) Approximate Resistance (kOhms)
32 0.0 30 - 32
33 0.6 28.5 - 29.5
35 1.7 24.5 - 25.5
40 4.4 22.5 - 23.5
50 10.0 15.5 - 16.5
60 15.6 12.1 - 13
75 23.9 10.1 - 11
80 26.7 9.1 - 10
85 29.4 8.1 - 9