Sears N9MP1, N9MP2, 9MPD Gas Valve Diagnostic Codes See Figure, Circulating Fan G Request, Off

Page 40

10. Sequence of Operation & Diagnostics

The following is the normal operating sequence for the control system.

Cooling (¥) Request:

24 VAC signals applied to Y & G terminals of EFT (electronic fan timer) control.

Cool motor speed energized after 6 second Cool Fan On Delay time.

Y & G signals removed from EFT.

Cool motor speed de-energized after 60 second Cool Fan Off Delay time.

Circulating Fan (G) Request:

24 VAC signals applied to G terminals of EFT control.

Heat motor speed energized without delay.

G signal removed from EFT.

Heat motor speed de-energized without delay.

Heating (W) Request:

24 VAC signals applied to W terminal of EFT control.

Inducer motor turns on.

The gas valve solenoid energizes.

Following a 3 second prepurge delay, the pilot valve opens and the ignitor begins to warm up.

After the pilot lights, the main burners energize and light.

Timed from the opening of the main gas valve, the control will delay 30 seconds before switching the fan to Heat speed.

W signal removed from EFT.

The gas valve de-energizes and the main burners go out.

The inducer runs at its present speed for a 30 second postpurge period.

Timed from the gas valve de-energizing, the Heat fan speed de-energizes after the selected Heat Fan Delay time expires.

Heating Request with Gas Supply Line Shut Off:

24 VAC signals applied to W terminal of EFT control.

Inducer motor turns on.

The gas valve solenoid energizes.

Following a 3 second prepurge delay, the pilot valve opens and the ignitor begins to warm up.

The ignitor glows red-hot for 30 seconds, then turns off.

The igniter stays off for 25 seconds, then begins to warm-up again.

The igniter glows red-hot for 30 seconds, then turns off.

The pilot valve closes 3 seconds after the igniter de-energizes.

The inducer de-energizes 5 seconds after the pilot valve closes.

The SmartValve proceeds to soft lockout and flashes error code 6.

The control exits soft lockout after 5 minutes and begins another ignition sequence.

Gas Valve Diagnostic Codes (See Figure 43)

OFF

 

 

 

 

=

Control

 

not

powered

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Heartbeat

 

 

 

 

=

Normal

 

Operation

 

(Standby

or

call for

heat)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

Flash

 

 

 

 

=

Not

used

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2

Flashes

 

 

 

 

=

Pressure

switch

closed

when

should

 

be

open

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3

Flashes

 

 

 

 

=

Pressure

switch

circuit

was

still

sensed

as open

 

30

seconds

after

the inducer

was

energized.

System is

 

 

 

 

 

 

 

in 5

minute delay

 

mode,

with

inducer

 

off. After

5-minute delay, a new ignition sequence will be initiated.

 

 

 

 

 

 

 

(Note:

SV9541M

 

On/Off

 

switch

 

in

off

 

position

during a call for

heat

will generate

this diagnostic

code)

4

Flashes

 

 

 

 

=

Limit

switch

string

open

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

Flashes

 

 

 

 

=

Flame

sensed out

of sequence

 

-

Flame

signal

still

present.

 

 

 

 

 

 

 

 

 

 

 

6

Flashes

+

1

Note

1

=

Soft

Lockout

-Maximum

 

retry

count

exceeded

 

(failed to

light

within

4 trials

for

ignition)

 

 

 

6

Flashes

+

2

Notes

1,2

=

Soft

Lockout

-Maximum

 

recycle

count

exceeded

 

-

Last

failure was Flame Sense Lost During Run

6

Flashes

+

3

Notes

1,2

=

Soft

Lockout

-Maximum

 

recycle

count

exceeded

 

-

Last

failure

was

Airflow

Proving

Circuit

 

Opened

 

 

 

 

 

 

 

During

 

Run

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

6

Flashes

+

4

Notes

1,2

=

Soft

Lockout

-Maximum

 

recycle

count

exceeded

 

-

Last

failure

was

Limit

Circuit Opened

During

Run

7

Flashes

 

 

 

 

=

Soft

Lockout

Due

 

to Limit

Trips

 

Taking

Longer

than

2 minutes

to

Reset;

Auto Reset

After

1

Hour

if

 

 

 

 

 

 

 

Call

for

 

Heat

Still

 

Present.

Reset

 

by

Cycling

Call

for

Heat

at

Any

Time.

 

 

 

 

 

 

 

NOTE 1 : The

6 + X designation

indicates

a combination

 

of flash

codes:

6 flashes

shows

the

control

is in soft

lockout,

followed

by X flashes

[_

44001 111400

Image 40
Contents SingleStage Denotes Brand MP D 0 75 F 12 a #JellJill 440 01 1114Date of Start-Up Furnace/Drip- Leg? YESCO2 ? Frozen Water Pipe Hazard Frozen and Burst Water Pipe HazardInstallation Typical Upflow InstallationLocation and Clearances Winter ShutdownInstallation Requirements Installation PositionsFurnace Installation Considerations LevelingDimensions & Clearances VENTrgMPDAiRI.TAKE TOPCombustion & Ventilation Air For Single Pipe Installation Air Openings and ConnectingDuctsHorizontal Furnace Installation Confined Space Installation RequirementsEhr Unconfined Space InstallationFree Area Venting and Combustion Air Check Vent CheckMake the Following Check HoodVent and Combustion Air Piping Single Pipe N9MP1 ModelsDirect Vent N9MP2 Models Dual Certified gMPDModelsPiping Insulation Guidelines Sizing Combustion Air and Vent PipePipe Diameter Table N9MP2 Models Vent Termination ClearancesCondensate Drain Trap Condensate Drain Trap Freeze ProtectionUnited States Only Canada See Canadian Fuel Gas Code OtherThanUpflow Installations Dual Certified *9MPD-A4 Models YellowPlasticCapDrainLine TransitionMountingScrews4 SomemodelsDrain HorizontalLeft Installations Dual Certified *9MPD-A4Models 25-24-12Switch Hose Si.g.Pre...reSwitchRpeept.oT \ e.spre X3L/\Page ReturnAir Page Left Side Venting Drainstubonthetransitionandsecurewitha3/4clamp Satetrapandsecurewitha3/4clamp Boxandsecurewitha3/4clampStubonthecondensatetrapandsecurewitha3/4clamp Inlet VentFitting TPipe & ClampsReturn Air Modelsshownhave Twopressureswitches CapReturn Air ClampsLeft Connecting Vent and Combustion Air Piping Combustion Air Pipe Connection Dual Certified orVent Pipe Connection PVCHorizontal Termination Proper Sealing Procedure for Combustion BlowerVent Pipe Using Exterior Risers Checkholesizesbymakingsureitissmallerthan the couVertical Termination Vent Termination ShieldingEi271Recommended Alternate Installation for Sustained Cold Concentric Vent and Combustion Air Sidewall TerminationSidewall Inlet Vent and Exhaust Air Termination Rooftop Inlet Vent and Exhaust Air TerminationManifold Gas Pressure Adjustment Alternate Btuh Input RatingsUSA OnlySupplyPressure Gas Supply PressureHigh Altitude Air Pressure Switch Changing Orifices for High AltitudeGeneral Derating Rules Changing OrificesTypical Gas Piping for Upflow Natural Gas Input Rating CheckExample Electrical Wiring Power SupplyWiringHumidifier/Electronic Air Cleaner Gas Piping RequirementsInstallation Fan Delay DIP Switch SettingsFan Timer Connections Ductwork and FilterFilter Installation using Optional Filter Rack SizingInsulation FiltersCombustible Floor Installation Availablefromyourdistributor StandoffFilterRackAddition Of Air Conditioning Ubbase for Combustible FloorFurnace Subbase Coil CabinetChecks and Adjustments Adjust Pilot BurnerTemperature Rise Check Main Burner Flame CheckTochecktemperaturerise,usethefollowingprocedure Heating and Continuous BlowerSpeed the SameChanging Blower Speed Continuous Fan OperationGas Valve Diagnostic Codes See Figure Circulating Fan G RequestHeating Request with Gas Supply Line Shut Off OFFTypical Gas Valve Honeywell Honeywell SV9541M Honeywell SV9541M Smart Valve Trouble shooting FlashesFlashes + Flashes + SoftLockoutVent Termination Clearances Concentric TerminationConcentric Vent Termination Kit # Arerequiredtocompletetheinstallation Concentric Vent Roof InstallationConcentric Termination Kit NAHA001CV & NAHA002CV Venting Rain Cap to Vent Pipe AssemblyConcentric Vent and Combustion Air Side Termination Concentric Vent Sidewall Attachment 25-22-02440011114O0 N9MP2075B12A4 N9MP2080F16A4 N9MP2100F14A4 N9MP2100J20A4 N9MP2125J20A4Save This Manual For Future Reference Denotes BrandSpecifications N9MP1 GeneralSpecifications N9MP2 Snap HW HSP HwhspNAHA001LV NAHAO01LV NAHA002LV PSC/I/2 PSC/II23OO Specifications 9MPDNAHA00SLV For 075 Models 3 Ton Units For 100 Models Ton 19 & 22314 UnitsFor 100 Models 5 Ton 223/4 Units For 125 Models 5 Ton UnitsConnection Diagram Disconnect Before Servicing Ladder DiagramD22 = = =@O,c25-23-95 FF18Key Description Part Functional125J 100J 125JO50B 075B 080F LOOF LOOJ 125J IoofLOOJ 125J Non-Functional Number 12A 1GAKeyDescription No. Non-Functional NgMP1 050B 075B 080F 100F 100J 125J Number100F 100J 16A 14A 20AKeyDescription No.Functional Heat Exchanger,Primary Heat Exchanger,SecondaryGMPD Number 050F12AKeyDescription No.Non- Functional Models *9MPDO50F12A4, Natural Gas Replacement part supplied 080J16ANon-Functional Key DescriptionNon- Functional Number

9MPD, N9MP1, N9MP2 specifications

The Sears N9MP2, N9MP1, and 9MPD are prominent models in the realm of residential heating systems, specifically designed to provide efficient and effective heating solutions. These models are part of Sears' commitment to quality and innovation, making them a popular choice among homeowners seeking reliability and performance.

The N9MP2 is a high-efficiency multi-speed gas furnace that boasts an impressive AFUE (Annual Fuel Utilization Efficiency) rating. This feature allows the furnace to convert a significant portion of fuel into usable heat, which effectively translates to lower energy bills for homeowners. The unit is equipped with a two-stage gas valve that provides increased comfort by adjusting the heating output based on demand, ensuring an even temperature throughout the home.

The N9MP1, like its counterpart, is known for its reliability and efficiency. It offers a single-stage operation that is ideal for homes needing consistent heating without the necessity for the more complex stages present in two-stage systems. This model also has a good AFUE rating, making it a cost-effective solution for families looking to reduce their heating expenses. Its design is tailored for easy installation and maintenance, allowing homeowners to keep their heating systems running at optimal performance without hassle.

The 9MPD model takes a step further with its advanced technology integration. It features a sophisticated control board that allows for easier diagnostics and enhanced system management. The 9MPD is also designed with quiet operation in mind, employing advanced sound-reduction technologies to minimize noise levels during heating cycles. Homeowners will appreciate the peace and quiet it brings, particularly in shared living spaces.

All three models are equipped with high-quality insulation and specialized heat exchangers that enhance their thermal efficiency. Additionally, they are designed with safety features such as automatic shut-off systems and robust flame rollout protection, ensuring a safe heating experience.

In terms of characteristics, these models are generally constructed with durable materials, designed to endure harsh weather conditions while providing consistent heating. They can be connected to various home automation systems, which adds to their appeal for tech-savvy consumers.

In conclusion, the Sears N9MP2, N9MP1, and 9MPD represent a comprehensive lineup of reliable, efficient, and technologically advanced heating systems suitable for contemporary homes. Their dedication to performance ensures that homeowners enjoy a warm and energy-efficient environment throughout the chilly seasons.