Norcold N109X, N109XIM Service Manual

WARNING

Service Manual

Gas/Electric Refrigerators

MODELS

N109XXX

N109XIMXX

DO NOT install this refrigerator in below deck marine applications. Do not

install this refrigerator in xed indoor cabin or other dwelling applications. This

refrigerator must use only NORCOLD designed and approved outside air intake

and exhaust ventilation for correct and safe operation. Any other ventilation
could cause lethal combustion exhaust fumes and or/explosive propane gas
fumes to be in the living area and/or below deck.

© 2004 THETFORD/NORCOLD. All rights reserved.

Publication No. 625352C (06-07-07)

TABLE OF CONTENTS

INTRODUCTION ........................................................... 3

About this Manual ............................................................... 3

Model Identication and Information Label ......................... 3

Cooling Unit Serial Number ................................................ 3

Certication and Code Requirements ................................. 3

About Installation ................................................................ 3

Replacement Parts ............................................................. 3

Technical Assistance ........................................................... 3

SAFETY AWARENESS................................................. 4

Safety Notice ....................................................................... 4

Attention & Safety Statements ............................................ 4

SPECIFICATIONS ......................................................... 5

TROUBLESHOOTING – QUICK REFERENCE GUIDE .... 6

N109X DISPLAYED FAULT CODES ............................ 7

TROUBLESHOOTING FLOWCHARTS ....................... 8

Blank Display – Refrigerator does not turn on .................... 8

no FL Fault Code – Burner failed to ignite or reignite ......... 9

Sr Fault Code – Flame sense circuit failure ...................... 10

dc LO Fault Code – Low dc voltage .................................. 10

dc HI Fault Code – DC voltage high ..................................11

dc rE Fault Code – DC relay stuck closed .........................11

no AC Fault Code – No AC power available ..................... 12

AC rE Fault Code – AC relay stuck closed ....................... 12

AC LO Fault Code – AC voltage low ................................. 13

AC HI Fault Code – AC voltage high ................................. 13

AC HE Fault Code – AC heater failed open ...................... 14

dr Fault Code – Door open for more than 2 minutes ........ 15

Lamp Switch Operation .................................. 15

Lamp Switch Testing Procedure ....................................... 15

N109X Backup Operation ............................... 16

Thermistor Failure Fault – Controls in Backup Operating

System mode .................................................................... 16

Backup Operating System (BOS) ..................................... 16

no co Fault Code – No cooling detected by the controls ......17

Power Board Resetting Procedure ................................... 17

VENTILATION ............................................................. 18

Roof Exhaust Venting ....................................................... 18

Air Intake Vent ................................................................... 18

Roof Exhaust Vent ............................................................ 18

Bafes ............................................................................... 19

Double Sidewall Venting ................................................... 20

LP GAS SYSTEM ....................................................... 23

Pressure Requirements .................................................... 23

Testing for LP Gas Leaks .................................................. 23

Components ...................................................................... 24

Solenoid Gas Valve & Connections .............. 24

Orice ............................................................... 24

Burner & Burner Tube .................................... 24

Flue & Flue Bafe ............................................ 25

Heat Deector .................................................. 25

Flame Appearance ............................................................ 25

Burner Cleaning Procedure .............................................. 26

ELECTRICAL REQUIREMENTS AND COMPONENTS 28

DC Voltage Requirements and Polarity ............................ 28

Power Board DC Fuse .................................... 28

DC Power Wiring Requirements ....................................... 28

AC/DC Converter as Power Source .................................. 28

Lamp Assembly ............................................... 28

Divider Heater .................................................. 28

AC Power Requirements .................................................. 29

AC Heater & AC Heater Circuit Fuse ............. 29

Power Board AC Power Cord ......................... 29

N109X Models

2

Ice Maker AC Power Cord .............................. 30

12 Vdc Ventilation Fan ...................................................... 30

COOLING UNIT .......................................................... 31

Description ........................................................................ 31

Heat Absorption .............................................. 31

Leveled Operation .......................................... 31

Gradual Decrease in Cooling Efciency ........................... 31

Cooling Performance Monitoring Control ......................... 31

Resetting the Power Board ............................ 32

Cooling Unit Monitoring Control Operation . 32

"no co" Fault Code ......................................... 32

Cooling Unit Vertical Bafe ............................................... 32

Refrigerant Leakage ......................................................... 32

Disposal of Cooling Unit .................................................... 32

Cooling System Diagnostic Flowchart .............................. 33

Replacing the Cooling Unit ............................................... 35

Removing the Refrigerator from the Enclosure ... 35

Removal of Cooling Unit ................................ 36

Installation of Replacement Cooling Unit ..... 36

Reinstallation of Refrigerator into Enclosure ... 39

ELECTRONIC COMPONENTS .................................. 39

Power Board Removal & Installation ......................... 40

CONTROLS ................................................................ 41

N109X Optical Control Assembly ...................................... 41

Front Box ......................................................... 41

Optical Control Assy Removal & Installation ... 41

Modes of Operation .......................................................... 42

AUTO AC Operation & AUTO LP Operation .... 42

Shift from AUTO LP GAS to AUTO AC .......... 42

No AC Power and No Flame ........................... 42

Troubleshooting No Flame and No AC Faults 42

AC Manual Mode .............................................................. 43

No AC Power or Loss of AC Power ............... 43

AC Power Restored ........................................ 43

Troubleshooting "no AC" Fault .................... 43

LP Manual Mode ............................................................... 43

Flame Fails to Ignite or Flame Goes Out ...... 43

DIAGNOSTIC MODE ................................................. 44

Accessing & exiting Diagnostic Mode ............................... 44

Changing Screens ............................................................ 44

Screens and Diagnostic Segments Information ................ 45

WIRING PICTORIALS AND DIAGRAMS ................... 47

ICE MAKER COMPONENTS AND SERVICE ............ 49

Specications .................................................................... 49

Wire Harness .................................................................... 49

Water Fill Tube & Line ....................................................... 50

12 Vdc Water Line Heater ................................................. 50

Water Valve Replacement Procedure ............................... 51

Water Valve Service .......................................................... 52

Ice Maker Troubleshooting Chart ...................................... 52

Replacing Ice Maker ......................................................... 53

Cycle Testing Ice Maker .................................................... 54

Checking Water Valve Operation ...................................... 54

Water Fill Adjustment ........................................................ 54

Checking Water Valve Solenoid Resistance ..................... 55

Checking Mold Heater Resistance .................................... 55

Checking Voltage to Motor ................................................ 55

Winterization ..................................................................... 55

Refrigerator Service Manual

INTRODUCTION

NORCOLD.

INC.

SIDNEY,

OHIO

pourle GPL, equipped por le propan

TESTED FOR LP GAS: EQUIPPED FOR PROPANE / Teste

4.20 Amps 500 Watts

SUPPLY

alimentati

11 "WC

10.5 "WC

BURNER
bruleur

120VAC
60Hz

12VDC

0.66 LBS

REFRIGERANT/frigorigene
R707

TEST PRESSURE /
D'ESSAI 800 PSI

3.30 Amps 40 Watts

SERIAL # / N de serie

XXXXXXX

MODEL # / N de modele

GROUP CODE / code de

INPUT / puissance

N1095RIM

For recreational vehicle installation
Min. Installation clearance 0" sides, top
bottom, back. Install only with Kit #3
See installation instructions

Pour installation vehicule de plaisance
Degagement minimum pour I'installation
0" cotes, haut,bas, arriere, Installer
uniquement avec latrousse n_3
Voir les instructions d'installation.
618860

30807

1500 BTUH

CSA-1.10-2003

REFRIGERATORS

ANZI Z221.19-2003

REFRIGERATORS

D

E

S

I

G

C

R

E

T

I

F

I

E

D

CERTIFIED

R

R

About this Manual

This service manual provides maintenance, diagnostic, and
repair information for

refrigerators. It is a reference tool designed for technicians
who are knowledgeable in the theory and operation of gas/
electric absorption refrigerators, liqueed petroleum (LP)

Norcold® model N109X gas absorption

About Installation

Refrigerator installation must conform with the N109X
Installation Manual for the Norcold® limited warranty to

be in effect. Installation must also comply with applicable

local codes and standards set by the cognizant

certication agency.

gas–propane–systems, and AC/dc electrical systems as
installed in a variety of recreational vehicles (RV).

All information, illustrations, and specications contained in

this publication are based on the latest product information
available at the time of publication. Norcold® reserves the
right to make changes at any time without notice.

Replacement Parts

Use only authorized
Generic parts do not meet
for safety, reliability, and performance. The use of
unauthorized aftermarket or generic replacement parts
voids the refrigerator's limited warranty coverage.

Model Identication

Model N109X is a 2-way refrigerator that can operate on AC

power or LP gas. The electronic controls operate on 12 volt DC.

Letter(s) appended to the model number identify factory

installed accessories. For example, an N109XIM is a
2-way refrigerator equipped with an ice maker.

Technical Assistance

If unable to resolve technical issues using the information

provided in this manual, technical support for service technicians
is available through the Norcold® Customer Service Center:

'Telephone: ...................................1-800-444-7210.

7Fax: ..............................................1-937-497-3183.

Certication and Code Requirements

®

Norcold

are certied under the latest edition of ANSI Z21.19B
standards for installation in mobile homes or recreational
vehicles.

refrigerators are also certied with the Canadian
Standards Association, CAN/CGA-1.4-M94.

Electrical components are compliant.

N109X gas/electric absorption refrigerators

®

Norcold

N109X gas/electric absorption

;World Wide Web: ............... www.norcold.com/cda.

This information is required to process technical support
requests:

nModel number.
nSerial number.
nMake, model, and year of recreational vehicle.

Norcold® replacement parts.

Norcold® specications

Information Label

The information label is located in the upper right corner

of the fresh food compartment just below the divider. (Fig.

1). The label provides this information:

nSerial number.
nModel number.
nLP gas (propane) pressure.
nBtu/hr.
nAC voltage and amperage.
nDC voltage and amperage.
nDesign certication.
nVent kit requirement.

Cooling Unit Serial Number

The cooling unit has a separate serial
number that appears on the cooling
unit bar code label. The label is

afxed to the surface of the cooling

unit leveling chamber (Fig. 2).

Figure 1. Refrigerator information label location

Figure 2. Cooling unit bar code label location

N109X ModelsRefrigerator Service Manual

3

SAFETY AWARENESS

WARNING

CAUTION

Safety Notice

It is not possible to anticipate all of the conceivable

ways or conditions under which the refrigerator may be
serviced or to provide cautions as to all of the possible
hazards that may result. Standard and accepted safety

precautions and equipment should be used when
working on electrical circuits and handling toxic or
ammable materials. Safety goggles and other required

protection should be used during any process that can
cause material to become airborne, such as removing a
leaking cooling unit and cleaning components.

Attention Statements

The safety alert symbol followed by the word
WARNING or CAUTION identies potential safety
hazards or conditions.

The safety alert symbol with the appropriate heading

Safety Statements

Do not modify, alter, or equip the refrigerator to the

use of any other fuel (natural gas, butane, etc.). N109X

refrigerators are designed and equipped for the use of

LP gas–propane gas–only.

Incorrect installation, adjustment, alteration, or

maintenance of the refrigerator can cause personal

injury, property damage, or both.

appears on all safety labels posted on the refrigerator
and safety awareness notices presented throughout this
manual.

The above heading identies hazards or conditions,
which if ignored can cause serious injury, death,
and/or extensive property damage.

The above heading identies hazards, which if
ignored can cause injury and/or property damage.

Do not use leak test solutions that contain

ammonia or chlorine. Ammonia and chlorine degrade

copper and brass components.

The cooling unit is a sealed system under

pressure! Do not try to repair or recharge the cooling

unit. Do not bend, drop, weld, drill, puncture, saw, or
strike the cooling unit.

Do not smoke, light res, or create sparks when

working on the propane gas system.

Do not use an open ame for leak testing any of

the propane gas system components. Propane gas is

highly ammable and explosive.

Always use two wrenches to tighten or loosen LP

gas connections. Damaged connections, piping, and
components create the potential for gas leaks.

All electrical connections and repairs to the

refrigerator must comply with all applicable codes. Refer

to the certication and code requirements section of the

N109X Installation Manual for more information.

Do not work on live electrical circuits. Turn off

AC power and DC power sources before attempting

to remove, service, or repair any of the refrigerator's
electrical or electronic components.

Do not modify, bypass, or eliminate any of the

refrigerator's electrical components, electronic circuits,
or propane gas system components.

Do not wet or spray liquids on or near electrical

connections or electronic components. Most liquids,

including leak detection solutions, are electrically
conductive and pose the potential for an electric shock
hazard, short electrical components, damage electronic

circuits, and/or ignite a re.

Handle a leaking cooling unit with extreme

caution! The cooling unit contains ammonia, hydrogen,

and sodium chromate. Ammonia can cause severe
skin and eye burns. Hydrogen is highly ammable,
can ignite, and burns with an intense ame. Certain

chromium compounds, such as sodium chromate, are
carcinogenic.

Do not use extension cords. Do not remove

the grounding prong from the refrigerator AC power

cord. Do not use a two prong adapter to connect the

refrigerator to the AC outlet.

Do not over-fuse electrical circuits. Use specied

fuses and AWG wire sizes. The "Specications" section

of this manual provides fuse size information. Refer to
the N109X Installation Manual for the correct AWG wire

size specications.

Prevent child entrapment! Before disposing of

the refrigerator, remove all doors and fasten all shelves
with retainers.

Some of the refrigerator's metal components have

sharp corners and edges. Wear hand protection, such

as cut resistant gloves, and exercise extreme care when

handling the refrigerator.

Make sure all hardware, such as hinges and

fasteners (retaining screws, etc.), is properly fastened.

4

N109X Models

Refrigerator Service Manual

SPECIFICATIONS

N109X Models

Storage volume

N109X -------------------------------------------------------------------------------------------------------------------------------- 9.5 ft3.

Rough opening dimensions (H x W x D)

N109X ------------------------------------------------------------------------------------------------------- 59

Decorative panels dimensions

Thickness ---------------------------------------------------------------------------------------------------------------------------­ Freezer door (H x W) ----------------------------------------------------------------------------------------- 14
Fresh food compartment door -------------------------------------------------------------------------------- 38

Controls

Type ------------------------------------------------------------------------------------- Electronic with built-in diagnostic function
ON/OFF/MODE/TEMP SET switches -----------------------------------------------------------------Raised pushbutton style

Temperature settings ---------------------------------------------------------------------------------------------- 1=cold, 9=coldest
Temperature sensor -----------------------------------------------------------------------------Thermistor, n mounted (10th n)

7

/8 in. x 23 1/2 in. x 24 in.

3

17

/32 in. x 21 19/32 in.

5

/8 in. x 21 19/32 in.

/16 in.

Off-level operating limits

Side-to-side--------------------------------------------------------------------------------------------------------3 degrees maximum
Front-to-back ------------------------------------------------------------------------------------------------------6 degrees maximum

DC power

Controls operating voltage ----------------------------------------------------------------------------------------- 10.5 to 15.4 Vdc
DC fuse (F1 in power board) ------------------------------------------------------------5 A (tan color), automotive blade type

DC amp draws (at nominal 12 VDC)

Automatic ignition ------------------------------------------------------------------------------------------------------------------ 0.50 A

Divider heater ----------------------------------------------------------------------------------------------------------------------- 0.25 A
Fresh food compartment lamp ------------------------------------------------------------------------------------------------- 0.46 A
Gas valve ---------------------------------------------------------------------------------------------------------------------------0.146 A
Fan ------------------------------------------------------------------------------------------------------------------------------------ 0.36 A

AC power

AC heater operating voltage requirements ----------------------------------------------------------------------108 to 132 VAC

Fuse ac heater circuit (F3 in power board) -------------------------------------- 5 A,

1

/4 in. x 1 1/4 in. AGC type fast acting

AC heater rating ----------------------------------------------------------------- 300 W/2.5 A @ 120 VAC (resistance of 48 Ω)

LP gas (propane)

Operating pressure ----------------------------------------------------------------------------------------------- 10.5 to 11.5 in. w.c.
Heat input ---------------------------------------------------------------------------------------------------- 1500 Btu/h @ 11 in. w.c.
Orice -----------------------------------------------------------------------------------------------------------------------------------LP16
Gas ignition ----------------------------------------------------------------------------------- Automatic with ame sensing circuit

Electrode tip-to-burner air gap ------------------------------------------------------------------------------------------

1

/8 to 3/16 in.

N109X ModelsRefrigerator Service Manual

5

TROUBLESHOOTING – QUICK REFERENCE GUIDE

Problem Possible Cause Checks/Reference

Ventilation restricted or obstructed.
Cooling unit problem.

No AC power to refrigerator.
F3 fuse in the power board open.
AC heater failed open.

Check LP gas supply and valves.
See page 8.
See page 8.
See page 9.

See page 7.
Check 12 volt DC connections.
Check fuse F1 (5 amp) in power board.

No 12 volt DC power to refrigerator.
Faulty/loose 12 volt DC connections.
F1 fuse in power board open.

See page 11.
Check fuse F3.
See page 13.

Ventilation obstructed.
AC voltage low.

Check enclosure for airflow obstructions.
See page 12.

No LP gas.
Incorrect electrode tip-to-burner gap.
Faulty spark/sense electrode assembly.
Flame sensing circuit failure.

Ventilation restricted or obstructed.
Incorrect LP gas pressure.
Dirty burner.
Missing flue baffle.
Heat deflector blocked.

Check enclosure for obstructed airflow.
See page 8.
See page 8.
See page 24.
See page 24.

The refrigerator does not turn ON.

The refrigerator does not cool on
ac power.

The refrigerator does not cool
efficiently on ac power.

The refrigerator does not operate
on LP gas.

The refrigerator does not cool on
any of the power sources.

The refrigerator does not
cool efficiently on LP gas.

Check enclosure for obstructed airflow.
See pages 16 and 30.

N109X Models

6

Refrigerator Service Manual

N109X DISPLAYED FAULT CODES

See page 15.

Flashing

Temp

Setting

Backup operating system in operation.

D

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p

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a

y

A

l

t

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r

n

a

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g

See pages 16
and 30.

Audible

Alarm

No cooling detected by the controls.

See page 14.

Audible

Alarm

Fresh food compartment door open more than 2 minutes.
Lamp reed relay switch faulty.

A

l

t

e

r

n

a

t

i

n

g

D

i

s

p

l

a

y

See page 13.

Audible

Alarm

AC heater failed open.

D

i

s

p

l

a

y

A

l

t

e

r

n

a

t

i

n

g

See page 12.

AC voltage high.

D

i

s

p

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a

y

A

l

t

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r

n

a

t

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g

See page 12.

AC voltage low.

A

l

t

e

r

n

a

t

i

n

g

See page 11.

D

i

s

p

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a

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Audible

Alarm

AC relay stuck closed.

D

i

s

p

l

a

y

A

l

t

e

r

n

a

t

i

n

g

See page 11.

Audible

Alarm

No ac power available to refrigerator.
AC cord not plugged into power board.
F3 fuse open.

D

i

s

p

l

a

y

A

l

t

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r

n

a

t

i

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g

See page 10.

DC voltage high.

Code

Probable Cause Reference

See page 7.

Blank

Display

Screen

Refrigerator turned off.
No 12 Vdc to refrigerator.
F1 fuse open.

D

i

s

p

l

a

y

A

l

t

e

r

n

a

t

i

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g

See page 8.

Audible

Alarm

The burner failed to ignite or reignite.

See page 9.

Audible

Alarm

Flame sense circuit failure.

D

i

s

p

l

a

y

A

l

t

e

r

n

a

t

i

n

g

See page 9.

DC voltage low.

N109X ModelsRefrigerator Service Manual

7

TROUBLESHOOTING FLOWCHARTS

Before beginning this procedure make sure:

■

The RV DC power system is supplying 10.5 to 15.4 volts to the refrigerator.

■

No other RV appliances or lighting circuits are connected to the refrigerator dc circuit.

■

12 volt DC input to the power board is wired according to the N109X Installation Manual.

Fault indicator displayed:

Measure voltage across
power board 12VDC and
GND1 connections

.

1. Low/no DC power input to power board.

2. Loose/faulty wiring or connectors.

NO

NO

YES

Check condition of F1 fuse
in power board. See Figure 3.

Replace fuse. Use a standard 5 amp
(tan color) automotive blade style fuse.

10.5 to

15.4 volts DC?

YES

Measure voltage at optical
control harness. See
Figure 4.

Replace power board.
See page 38.

YES

Voltage

present?

NO

Replace optical control assembly.
See page 39.

F1 fuse okay?

Wire harness optical
control display connector

White/red wire

White/violet wire

87

III

V

10.5 to 15.4 volts DC

V

mA

A

mV

V

V

OFF

A

COM

V

mA

m

A

m

A

87

III

Good= 00.0

W

00.0

Bad = OL

F1 Fuse

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

Blank Display – Refrigerator does not turn on

Figure 3. Checking the dc fuse

8

continuity

N109X Models

Figure 4. Measurement points for wire harness voltage

Refrigerator Service Manual

no FL Fault Code – Burner failed to ignite or reignite

Air gap

1/8 to 3/16

inch?

Burner
clean?

Before beginning this procedure make sure:

■

RV LP gas tank valve is open.

■

Refrigerator solenoid gas valve manual shutoff is open.

■

LP gas pressure at the solenoid gas valve pressure tap is 10.5. to 11.5 in. w. c.

Clean and service burner.
See page25.

NO

YES

Check that electrode tip-to­burner air gap is correct.

NO

Set electrode-to-burner air gap
1/8 to 3/16 inch.

YES

Continuity?

Check spark/sense electrode
assembly for continuity.

NO

Replace spark/sense electrode
assembly.

Voltage?

YES

Check voltage across power
board terminals GV and
GV GND.

NO

Replace power board.

Continuity?

YES

Check gas valve solenoid
wires for continuity.

NO

Replace gas valve wires.

YES

Check gas valve solenoid
resistance.

.

NO

Replace gas valve.

79 to 85 Ω?

Check burner condition.

YES

Faulty or obstructed gas valve.
Replace gas valve.

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

D

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A

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Audible

Alarm

N109X ModelsRefrigerator Service Manual

9

Sr Fault Code – Flame sense circuit failure

Fault indicator displayed:

Replace power board.
See page 38.

Flame sense circuit failure.

ON

TEMP
SET

MODE

ON-OFF

1-COLD COLDEST-9

Voltage

lower than

10.5 volts?

NO

Check RV 12 volt DC power supply to
the power board.

YES

See NOTE below to determine
and correct "dc LO" fault.

Check for DC voltage input
to power board terminals
12VDC and GND1.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

A

l

t

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r

n

a

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g

D

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p

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y

Before beginning this procedure:

■

Make sure RV DC voltage to refrigerator is 10.5 to 15.4 volts.

■

Determine if the "dc LO" fault code displays when the converter is the source of DC power.

■

Make sure no other appliance or lighting circuit is connected to the refrigerator DC circuit.

Fault indicator displayed:

dc LO Fault Code – Low dc voltage

NOTE

Electronic controls operate on 12 volt DC. When an AC/DC converter is

used to supply DC power, the refrigerator circuit must be connected to the

appliance output terminals of the converter (ltered side).

If the refrigerator circuit is connected to the unltered side the AC ripple

10

N109X Models

generated by the converter may cause a "dc" "LO" fault code to display.

To troubleshoot a "dc" "LO" fault, connect a charged 12 volt automotive
battery to the power board. If the "dc" "LO" code clears, the fault was
caused by unltered DC power.

If the "dc LO" code does not clear, replace the power board (see page 38).

Refrigerator Service Manual

dc HI Fault Code – DC voltage high

Fault indicator displayed:

Replace power board.
See page 38.

DC heater relay stuck closed.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

A

l

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D

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Before beginning this procedure:

n

Make sure RV DC voltage to refrigerator is 10.5 to 15.4 volts.

n

Determine if the "dc HI" fault code displays when the converter is the source of DC power.

Fault indicator displayed:

Voltage

higher than

15.4 volts?

NO

Check RV DC power distribution to
refrigerator.

YES

See NOTE below to determine
and correct "dc HI" fault.

Check for DC voltage input
to power board terminals
12VDC and GND1.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

A

l

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D

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NOTE

Electronic controls operate on 12 volt DC. When an AC/DC converter is

used to supply DC power, the refrigerator circuit must be connected to the

appliance output terminals of the converter (ltered side).

If the refrigerator circuit is connected to the unltered side the AC ripple
generated by the converter may cause a "dc " "HI " fault code to display.

To troubleshoot a "dc " "HI" fault, connect a charged 12 volt automotive
battery to the power board. If the "dc" "HI" code clears, the fault was caused
by unltered DC power.

If the "dc LO" code does not clear, replace the power board (see page 38).

dc rE Fault Code – DC heater relay stuck closed

N109X ModelsRefrigerator Service Manual

11

no AC Fault Code – No AC power available

Before beginning this procedure make sure:

?

No other problems exist with the RV AC power supply.

?

No other appliances or lighting circuits are connected to the refrigerator AC circuit.

?

Extension cords are not being used to supply AC power to the refrigerator.

Fault indicator displayed:

F3 fuse okay?

1. Check AC power input from RV to unit.

2. Check for faulty AC power cord.

NO

NO

YES

Check condition of F3 fuse
in power board.

Replace fuse. Use only a 5 amp,

1

/4" x 11/4"

AGC type fuse.

108

to

132 volts?

YES

Check that fuse holder clips
are making full contact with
fuse.

Adjust clips to ensure fuse contacts are
firm in clips and making full contact.

YES

Clips okay?

NO

Replace power board.
See page 38.

Measure voltage at power
board AC cord connection.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

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Fault indicator displayed:

Replace power board.
See page 38.

AC heater relay stuck closed.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

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AC rE Fault Code – AC heater relay stuck closed

12

N109X Models

Refrigerator Service Manual

AC LO Fault Code – AC voltage low

Before beginning this procedure:

■

Determine if a certain AC power source sets the "AC” “LO" fault code (generator, shore power, inverter).

■

Make sure no other appliance or lighting circuit is connected to the refrigerator AC circuit.

■

Make sure extension cords are not being used to supply AC power to the refrigerator.

Fault indicator displayed:

Fault related to RV AC power distribution
component or circuit supplying AC power
to refrigerator.

YES

NO

Replace power board.
See page 38.

Voltage
lower than
108 volts?

Measure voltage at power
board AC cord connection.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

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Before beginning this procedure:

■

Determine if a certain AC power source sets the "AC HI" fault code (generator, shore power, inverter).

Fault indicator displayed:

Fault related to RV AC power distribution
component or circuit supplying AC power
to refrigerator.

YES

NO

Replace power board.
See page 38.

Voltage

higher than

132 Vac?

Measure voltage at power
board ACcord connection.

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

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AC HI Fault Code – AC voltage high

N109X ModelsRefrigerator Service Manual

13

AC HE Fault Code – AC heater failed open

AC heater resistance 38 to 53

Ω.

Before beginning this procedure make sure:

n

RV AC voltage to the refrigerator is 108 to 132 volts.

n

No other appliance or lighting circuit is connected to the refrigerator AC circuit.

Fault indicator displayed:

Heater

connections

okay?

NO

YES

Check AC heater resistance.
See Figure 5.

NO

Replace AC heater.
See page 28.

YES

Replace power board.
See page 38.

Check AC heater wires for
loose or damaged connection.

Resistance
38 to 53

Ω

?

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

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Repair or replace connectors. If
connectors cannot be replaced,
replace heater. See page 28.

Multimeter set to

Ohms scale

Figure 5. Measuring AC heater resistance.

N109X Models

14

Refrigerator Service Manual

dr Fault Code – Door open for more than 2 minutes

Before beginning this procedure make sure:

■

Light/thermistor connector and wire harness connector are fully engaged and locked.

Fault indicator displayed:

Adjust striker plate.

NO

YES

Check for correct door
installation. See NOTE below.

NO

Test lamp switch operation. See switch
test procedure below.

YES

Check for location of magnet if the door
swing was changed. See NOTE below.

Check that the door latch
striker plate is adjusted
correctly.

Was door

swing

changed?

Striker plate

okay?

Audible

Alarm

ON

TEMP
SET

MODE

ON-OFF

1-COLD COLDEST-9

Food Compartment Lamp Switch

A reed relay switch turns the fresh food compartment

light on and off. This switch is an integral component of
the optical control display board circuitry.

Lamp Switch Operation

The lamp switch operates using a permanent magnet
located underneath the fresh food compartment door
cap. When the door is fully closed, the magnet pulls and
maintains the switch contacts open (light off). Opening
the door breaks pull the door cap away from the switch,
causing the switch contacts to close (light on).

Always follow the instructions provided in the

Owner's Manual to change the refrigerator door
swing. The bottom door trim does not have a

magnet. Inverting the doors will required non­approved modications and will cause the fresh

food compartment light to remain on when the door
is closed.

NOTE

Lamp Switch Testing Procedure

1. Slide a magnetic screwdriver tip or a small magnet
on the underside of the optical control assembly
as shown in Figure 6.

2. Check the food compartment light as the
screwdriver tip is moved under the display:

nThe light should turn off when the magnetic

screwdriver tip or magnet passes under the optical
control assembly.

nThe light should turn on when the magnetic

screwdriver tip or magnet is distanced from the
underside of the optical control assembly.

3. If the light does not turn off when the magnet

passes under the optical control display, replace
the optical control display assembly. See page 39.

Figure 6. Testing light switch operation.

N109X ModelsRefrigerator Service Manual

15

Thermistor Failure Fault – Controls in Backup Operating System mode

Before beginning this procedure:

■

Make sure lamp/thermistor assembly is connected to the wire harness.

Fault indicator displayed:

Thermistor

Lamp

Connection

Thermistor

Connections

Clean/repair terminals or connector as
required. See Figure 7.

NO

Check thermistor resistance.
See Figure 8 below.

Wires and
connector

good?

Check lamp/thermistor wire
assembly and connector for
dirty/broken connections.

YES

Thermistor packed in ice bath

Temperature* Resistance*
(oF) (k )
85 8.1– 9.0
80 9.1–10.0
75 10.1–11.0
70 11.1–12.0
60 12.1–13.0
50 15.5–16.5
40 22.5–23.5
35 24.5–25.5
33 28.5–29.5
32 30.0–32.0

*

Approximate Values

ON

TEMP
SET

MODE

ON-OFF

1-COLD COLDEST-9

Te mp
Setting
Flashing

As the thermistor cools in the ice bath
the resistance value goes up. When the
thermistor is exposed to warmer temperatures
the reisistance reading goes down See Ta ble.

Multimeter set to
kOhms function.

Figure 7. Thermistor terminals and connector.

Backup Operating System (BOS)

The backup operating system (BOS) is an electronically

controlled duty cycle. It maintains the refrigerator

in operation if the thermistor is is open, shorted or
disconnected from the circuit. BOS maintains cooling by

controlling the heat source selected. In BOS the length

of the cooling cycle is controlled by a timer.

To accomplish this, the BOS adjusts the length of the

cooling cycle according to the temperature setting
selected by the user; the higher the temperature

setting, the longer the cooling cycle. For example, if

the temperature setting is set to 5, raising the setting
to 6 will lengthen the cooling cycle, resulting in lower
refrigerator temperature.

When a warmer temperature is desired, changing the
temperature setting to a lower number shortens the

N109X Models

16

Figure 8. Checking thermistor resistance.

cooling cycle. For example, if the temperature setting is

set to 6, lowering the setting to 5 will shorten the cooling
cycle, resulting in warmer refrigerator temperatures..

N109X Backup Operation

When the N109X controls shift to BOS operation, the

temperature setting ashes for ten seconds when the
TEMP button is pressed. After ten seconds, the "ON"

LED displays.

Refrigerator Service Manual

no co Fault Code* – No cooling detected by the controls

Pin 16

White/violet wire

To pin 15

Ground Lug

Insulated wire jumper

22 AWG with 1/2" long stripped ends

Fault indicator displayed:

NO

YES

Check for completion of
cooling cycle after resetting
power board.

NO

Cooling unit is good. Recheck for
ventilation obstructions and leveled
operation.

YES

Check for cooling at fin
assembly.

"no" "co"

code shows

before cycle

end?

Cooling

detected?

Audible

Alarm

ON

TEMP

SET

MODE

ON-OFF

1-COLD COLDEST-9

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1. Check for ventilation obstructions
and leveled operation.

2. Reset power board as shown in
Figure 9 and described in procedure
below.

3. Allow unit to operate normally.

1. Replace cooling unit if "no co"
shows before completing a full
cooling cycle.

2. Reset power board as shown in
Figure 9 and described in procedure
below.

* For more information on the "no co" fault code, see
pages 30-33

Power Board Resetting Procedure

1. Turn OFF the refrigerator.

2. Disconnect the following from power board:

a. 12 VDC positive and negative wires.

b. AC power cord.

c. Solenoid gas valve wires.

d. Spark/sense electrode assembly wires.

3. Remove the power board cover.

4. Reconnect 12 VDC positive and negative wire.

5. Turn ON the refrigerator.

6. Locate Pin 15 on 16 pin connector (P1). Pin 15

is the empty socket to the right of the white/violet

wire on the top row. See Figure 9.

7. Using a 14 AWG size insulated jumper wire, jump
Pin 15 to the power board ground lug for 10 ­15seconds. A click sound will indicate when the

controls reset. See Figure 9.

NOTE

A jumper wire to jump Pin 15 to ground can be
made from a 8-inch long insulated 14 AWG wire by
stripping 1/2 inch of insulation from each end.

8. Turn OFF the refrigerator.

9. Turn ON refrigerator. If "no co" code displays,
repeat steps 7 - 9.

10. Turn OFF the refrigerator.

11. Disconnect the 12 VDC power positive and

negative wires from the power board.

12. Install the power board cover.

13. Reconnect the following to the power board:

a. Spark/sense electrode assembly wire.

b. Solenoid gas valve wires.

c. AC power cord.
d. 12 VDC positive and negative wires from the

power board.

14. Place refrigerator in service.

Figure 9. Resetting the power board.

N109X ModelsRefrigerator Service Manual

17