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A02204b

11

NO PREVIOUS CODE 

 Stored codes

are er

ased after 72 hours

.  On RED LED

boards stored status codes can also be

er

ased whene

v

er po

w

er (115V or 24V)

is interr

upted.

  Run system through a

heating or cooling cycle to chec

k system.

12

BLO

WER ON AFTER PO

WER UP 

(115V OR 24V) 

 Nor

mal oper

ation.

Blo

w

er r

uns f

or 90 seconds

, if unit is

po

w

ered up dur

ing a call f

or heat (R-W

closed) or when (R-W opens) dur

ing the

b

lo

w

er on-dela

y per

iod.

1

3

LIMIT CIRCUIT LOCK

OUT 

 Loc

kout

occurs if the limit or flame rollout s

witch is

open longer than 3 min

utes

.  Control will

auto-reset after 3 hours

.  See code 33.

1

4

IGNITION LOCK

OUT 

 System f

ailed to

ignite gas and pro

v

e

 flame in 4 attempts

.

Control will auto-reset after 3 hours

.

See status code 34.

21

GAS HEA

TING LOCK

OUT 

 T

u

rn

 off

po

w

er and w

ait 5 min

utes to retr

y.

Chec

k f

o

r:

-

Stuc

k closed gas v

alv

e rela

y on control.

-

Mis

wire or shor

t to gas v

alv

e wire

.

2

2

ABNORMAL FLAME-PR

O

VING SIGNAL

Flame is pro

v

ed while gas v

alv

e is de-

energiz

ed.

  Inducer will r

un until f

ault is

cleared.

  Chec

k f

o

r:

-

Stuc

k open or leaky gas v

alv

e

.

23

PRESSURE SWITCH DID NO

T OPEN

Chec

k f

o

r:

-

Obstr

ucted pressure tube

.

-

Pressure s

witch stuc

k closed.

2

4

SECOND

AR

V

O

LT

A

G

E FUSE IS OPEN

Chec

k f

o

r:

-

Shor

t circuit in secondar

y v

oltage (24V)

wir

ing including ther

mostat leads

.

Disconnect ther

mostat leads to isolate

shor

t circuit.

3

1

PRESSURE SWITCH DID NO

T CLOSE

OR REOPENED 

 If open longer than 5

min

utes

, inducer shuts off f

or 15 min

utes

bef

ore retr

y.

  If opens dur

ing b

lo

w

er on-

dela

y per

iod, b

lo

w

er will come on f

or the

selected b

lo

w

er off-dela

y.

  Chec

k f

o

r:

-

Proper v

ent sizing.

-

L

o

w

 inducer v

oltage (115V).

-

L

o

w

 inlet gas pressure (if LGPS used).

-

Inadequate comb

ustion air supply

.

-

Disconnected or obstr

ucted pressure

tubing.

-

Def

ectiv

e inducer motor

.

-

Def

ectiv

e pressure s

witch.

-

Excessiv

e wind.

-

Restr

icted v

ent.

33

LIMIT CIRCUIT F

A

UL

 Indicates the

limit or flame rollout s

witch is open.

 Blo

w

e

r

will r

un f

or 4 min

utes or until open s

witch

remak

es whiche

v

er is longer

.  If open

longer than 3 min

utes

, code changes to

loc

k

out #13.

  If open less than 3 min.

status code #33 contin

ues to flash until

b

lo

w

er shuts off

.  Flame rollout s

witch

requires man

ual reset.

  Chec

k f

o

r:

-

Dir

ty filter or restr

icted duct system.

-

Loose b

lo

w

er wheel.

-

Def

ectiv

e s

witch or connections

.

-

Def

ectiv

e b

lo

w

er motor or capacitor

.

-

Inadequate comb

ustion air supply 

(flame rollout s

witch open).

-

Restr

icted v

ent.

-

Proper v

ent sizing.

-

Excessiv

e wind.

-  Blo

w

er motor on incorrect speed tap

.

-  Input r

ate to fur

nace set too high.

3

4

IGNITION PR

O

VING F

AILURE 

 If flame

is not sensed dur

ing the tr

ial f

or ignition

per

iod, the control will repeat the ignition

sequence 3 more times bef

ore loc

k

out

#14 occurs

.  If flame signal is lost dur

ing

the b

lo

w

er on-dela

y per

iod, b

lo

w

er will

come on f

or the selected b

lo

w

er off-dela

y.

 Chec

k the f

ollo

wing items first bef

ore

proceeding to the ne

xt step

.

-

Gas v

alv

e tur

ned off

.

-

Man

ual shut-off v

alv

e

.

-

Green/Y

ello

w wire MUST be connected

to fur

nace sheet metal.

-

Flame sensor m

ust not be g

rounded.

T

o

 deter

mine whether the prob

lem is in

the gas v

alv

e

, igniter

, or flame sensor the

system can be oper

ated in the component

test mode to chec

k the igniter

.  First

remo

ve

 the R ther

mostat connection from

the control and initiate the component

test sequence

.  Does the igniter glo

w

or

ange/white b

y

 the end of the 15 second

w

a

rm-up per

iod?

Unplug igniter har

ness from control and initiate

another component test sequence

.  Chec

k

for 115V betw

een pin 1 and NEUTRAL-L2 on

the control.

  

W

as 115V present f

or the 15

second per

iod?

Reconnect the R ther

mostat lead and set

ther

mostat to call f

or heat.

  Connect v

oltmeter

across gas v

alv

e connections

.  Does gas v

alv

e

receiv

e 24V?

Does gas v

alv

e open and allo

w gas to flo

w?

Do the main b

u

rners ignite?

Do the main b

u

rners sta

y on?

Repeat call f

or heat and chec

k flame sensor

current dur

ing tr

ial f

or ignition per

iod.

  Is the

DC microamps belo

w 0.5?

Is current near typical v

alue?

Will main b

u

rners ignite and sta

y on?

Fix

ed.

Clean flame sensor with fine steel w

ool and

rechec

k current.

  Nominal current is 4.0 to 6.0

microamps

.

45

CONTR

OL CIRCUITR

Y LOCK

OUT

A

uto-reset after 1 hour loc

k

out due to:

-

Flame circuit f

ailure

.

-

Gas v

alv

e rela

y stuc

k open.

-

Softw

are chec

k error

.

Reset po

w

er to clear loc

k

out.

  Replace

control if code repeats

.

Replace fur

nace control.

Chec

k f

or contin

uity in the har

ness and igniter

.

 Replace def

ectiv

e component.

Chec

k connections

.  If OK, replace control.

Chec

k that all gas v

alv

es are tur

ned on.

Replace v

alv

e

.

Chec

k f

o

r:

-

Inadequate flame carr

y

o

v

er or rough

ignition.

-

L

o

w

 inlet gas pressure

.

-

Proper fir

ing r

ate

.

-

Chec

k f

or air leakage around igniter br

ac

ket.

Allo

w b

lo

w

er to come on and repeat test to

chec

k f

or inter

mittent oper

ation.

Chec

k connections and retr

y.

  If current is

near typical v

alue (4.0-6.0 nominal) and

b

u

rners will not sta

y on, replace control.

Replace electrode

.

Replace fur

nace control.

YES

YES

YES

YES

NO

YES

YES

YES

NO

YES

NO

NO

NO

YES

NO

NO

NO

NO

15

Summary of Contents for GAS FURNACE 58MXA

Page 1: ...aning com pounds plastic or plastic containers gasoline kerosene cigarette lighter fluid dry cleaning fluids or other volatile fluids 3 Paint thinners and other painting compounds paper bags or other paper products Failure to follow this warning can cause corrosion of the heat exchanger fire personal injury or death NOTE Read the entire instruction manual before starting the installation This symb...

Page 2: ...talled in any of the 4 positions shown in Fig 2 you may need to revise your orientation to component location accordingly ELECTROSTATIC DISCHARGE ESD PRECAUTIONS Electrostatic discharge can affect electronic components Take precautions during furnace installation and servicing to protect the furnace electronic control Precautions will pre vent electrostatic discharges from personnel and hand tools...

Page 3: ...et adjacent to furnace 1 Turn off electrical supply to furnace 2 Remove filter cabinet door 3 Slide filter out of cabinet 4 If equipped with permanent washable filter clean filter by spraying cold tap water through filter in opposite direction of airflow Rinse filter and let dry Oiling or coating of the filter is not recommended 5 If equipped with factory specified disposable media filter replace ...

Page 4: ...stall blower assembly in furnace 11 Reinstall control box transformer and door switch assembly on blower shelf 12 Reinstall condensate trap and tubing if previously removed a Reinstall condensate trap in hole in blower shelf b Connect condensate trap drain tubes See Fig 8 or tubing diagram on main furnace door for proper tube location NOTE Ensure tubes are not kinked or pinched as this will affect...

Page 5: ...exchangers get an accumulation of light dirt or dust on the inside they may be cleaned by the following procedure NOTE If the heat exchangers get a heavy accumulation of soot and carbon both the primary and secondary heat exchangers should be replaced rather than trying to clean them thoroughly due to their intricate design A build up of soot and carbon indicates that a problem exists which needs ...

Page 6: ...ndary heat exchangers CANNOT be serviced or inspected A small number of bottom outlet openings can be inspected by removing the inducer assembly See Flushing Collector Box and Drainage System section for details on removing inducer assembly Step 5 Flushing Collector Box and Drainage System 1 Turn off gas and electrical supplies to furnace 2 Remove main furnace door 3 Disconnect inducer motor and p...

Page 7: ...UE PLUGGED END COLLECTOR BOXDRAIN TUBE BLUE WHITE STRIPED COLLECTOR BOX TUBE GREEN COLLECTOR BOX TUBE PINK COLLECTOR BOX EXTENSIONTUBE CONDENSATE TRAP INDUCER HOUSINGDRAIN TUBE VIOLET COLLECTOR BOX EXTENSION TUBE COLLECTOR BOXTUBE PINK COLLECTOR BOX DRAIN TUBE BLUE COLLECTOR BOX TUBE GREEN CONDENSATE TRAP INDUCER HOUSINGDRAIN TUBE VIOLET COLLECTOR BOX EXTENSION TUBE COLLECTOR BOXDRAIN TUBE BLUE WH...

Page 8: ...block out of bracket 6 To replace igniter igniter assembly reverse items 5a through 5d 7 Reconnect igniter wire connection 8 Turn on gas and electrical supplies to furnace 9 Verify igniter operation by initiating furnace control board self test feature or by cycling thermostat 10 Replace main furnace door Step 7 Electrical Controls and Wiring There may be more than 1 electrical supply to the unit ...

Page 9: ...d must be replaced use same type or equivalent wire W Y Y2 GND THERMOSTAT TERMINALS 1 2 3 Fig 12 Control Center A02142 BLW NUETRAL STATUS CODE LED SEC 2 SEC 1 EAC 2 L2 FUSE 3 AMP 0 5 AMP 24VAC HUM TEST TWIN Y1 DHUM G COM W W1 Y Y2 R 24V PLT 120 180 90 150 BLOWER OFF DELAY PLT 1 COOL HEAT SPARE 1 SPARE 2 FAN EAC 1 1 AMP 115VAC PR 1 L1 PL2 1 24 V THERMOSTAT TERMINALS 3 AMP FUSE LED OPERATION DIAGNOS...

Page 10: ... heat tape insulation If any damage or discolored insulation is evident replace heat tape 3 Check that heat tape power supply circuit is on Step 9 Winterizing Freezing condensate left in the furnace will damage the equipment If the furnace will be off for an extended period of time in a structure where the temperature will drop to 32 F or below winterize as follows 1 Turn off electrical supply to ...

Page 11: ...nger periods of time as the control will assume an overtemperature condition exists and will respond with blower operation This places the control in the status recall mode and displays the last code stored in memory Record the code After the last code is displayed the control will perform the component test and then return to normal standby mode COMPONENT TEST Blower access panel door switch open...

Page 12: ...UM 24VAC HUMIDIFIER CONNECTION 0 5 AMP MAX IDM INDUCED DRAFT MOTOR PSC IDR INDUCED DRAFT MOTOR RELAY SPST N O ILK BLOWER ACCESS PANEL INTERLOCK SWITCH SPST N O J1 BLOWER OFF DELAY JUMPER SELECTOR JB JUNCTION BOX LED LIGHT EMITTING DIODE FOR STATUS CODES AMBER LGPS LOW GAS PRESSURE SWITCH SPST N O LS LIMIT SWITCH AUTO RESET SPST N C OL AUTO RESET INTERNAL MOTOR OVERLOAD TEMPERATURE SWITCH N C PCB P...

Page 13: ...ing 31 PRESSURE SWITCH DID NOT CLOSE OR REOPENED If open longer than five minutes inducer shuts off for 15 minutes before retry Check for Excessive wind Proper vent sizing Defective inducer motor Low inducer voltage 115VAC Defective pressure switch Inadequate combustion air supply Restricted vent Disconnected or obstructed pressure tubing Low inlet gas pressure if LGPS used If it opens during blow...

Page 14: ...test sequence The inducer will start and run for the entire component test The HSI blower motor FAN speed AMBER LED boards only HEAT speed and COOL speed will run for 10 15 seconds each Gas valve and humidifier will not be turned on Was there a previous status code other than 11 Is door switch closed Is there 115V going to switch Replace door switch Replace transformer Does the control respond to ...

Page 15: ...stricted vent Proper vent sizing Excessive wind Blower motor on incorrect speed tap Input rate to furnace set too high 34 IGNITION PROVING FAILURE If flame is not sensed during the trial for ignition period the control will repeat the ignition sequence 3 more times before lockout 14 occurs If flame signal is lost during the blower on delay period blower will come on for the selected blower off del...

Page 16: ...31 58mxa9sm Manufacturer reserves the right to discontinue or change at any time specifications or designs without notice and without incurring obligations Book 1 4 Tab 6a 8a PC 101 Catalog No 535 80099 Printed in U S A Form 58MXA 9SM Pg 16 11 02 Replaces 58MXA 8SM ...

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