FLAME SAFEGUARn CONTRULS phần 6 potx

Limit switch open in main JXlwer line or in series with the C{ltroller.. Adiust pilot position so 11ame will ignite main burner.. Pilot line tap on main fuel line is downstream of main p

R4138C,D INDUSTRIAL FLAME SAFEGUARD

CONTROLS (FIG 65)

These controls directly replece older R4138A and B

models to meet the lates! rElQJirements They are espe­

cially Suitable where Icng petilXi3 01 burner operation with·

out s/'lulc:bwn are normal, such as in heat-treating ovens

and kilns The R4138D is (he same as the R4138Cwl!hthe

adc:lilion 01 a jXl'I'Ver failure override circuit 10 prevent shut­

Ing of 1 Second or less) The A4138C is available in 120,

220, and.24O volt rtlOdeIS; the A4138D Is available only in a

120 vol'model

SAFETY FEATURES

The A4138C and D provide a Safe Start Check for a

flame, or a condition simulating a flame, at startup If the

flame"relay 2K is pulled in before the STAAT button is

pressed• 2K.2 is open, preventing the load relay 1K from

pulling in The system cannol be started until the condition

Is corrected and 2K drops PUt

They also prOVide safety shutdown on­

- failure to Ignite the pilor (lockout will occur t1the

START button is held in IClIlg9f than the 10ckPUt

switch liming.)

-loss 01 flame during the rUl"l period

-failure in the flame detectiCfl system, If e sell·

cheCking system is' used-see Table II (L.ockoul

will occur it lhe START b rIlon is held in longer

than the lockout switch timinQ.)

On safety shutdown the pilot and main fuel valve(s) are

de-energized 11 used, the exlernal alarm is energized The STAAT bulton must be manu8JJy pressed to restart the

system "the lockout switch trips the load relay 1K drq:>s Oul and the lockout switch must be manually reset to rEt­start the system

OTHER FEATURES

" A plu~in $4.27D Purge Timer is available as an ac· cessory (0 provide e timed purge period prior to the manual startup

" An optionei remole reset assembly allows resetting the lockout switch from a remote location

" Irlcandescent indicator lamps (FLAME OFF, PURGE COMPLETE, FLAME ON) prOVide a visual check: 011he system condl1ion

• The R4138C or D plugs into a subbase or cabinet ElQJiA?OO with quick-connect C'-ontacts

• All field wirinQ (except for the optional remote reset assembly) is connected to a terminal strip on the subbase or In the cabinet The R4138 can be re­moved easily withoul disconnecting any w·lring

" Clear plastic relay covers help prevent conlamina­tion, damage, end lamperinQ

" An ALARM terminal Is available to operate an exler­nalline voltage alarm on salety shutdown

" A zinc-dichromate finish resists the corrosive ef­fects 01 most induslrial atmospheres

KEYED IIECEPTA(L[

FOR PlUG·IN AMPliFIER SPRI",!> CL'P

01'1 CHASSI~

PlUG·I", FlAME SIGNAl

FIG 55-COMPONENTS OF THE R4138C OR O

186

- - - -

SEOUENCE OF OPERATION FOR THE R4138C

OR D (FIG 66)

The cperalion orlhe 120voll models oflhe R4138Cand

D win be described Theseq.Jel1ceofoperalion for a 220 or

240 volt model ot the R4138C is the same; it just has an

aci:jitionaltransformer 10 provide 120 volts tor the sMutler

& "'L.CIT UN Ju M; , II:(U_O '0"'" ce OO

'IOCIl """T eAT><I LIN - IT I.SO ~U-"'"

& ' n o' ,"" c""11 D.' "" I"II:UO: ULT

~=,:.~~,':;'~': ':':'~~~'~;;~Uc'=:"~;;.'Jo~~J ~"u."'''- u f l'H€ - ,

& IF • ., " ST••' ' "••""" , roar 0 TH, IT""" ""'TC" ,

FIG 66- SIMPLIFIED SCHEMATIC DIAGRAM OF TME 120 VOLT MODELS OF THE R4138C AND D

SHOWING TYPICAL FIELD WIRING FOR A GAS OR OIL CUTOFF SYSTEM

SEQUENCE OF OPERATION FOR THE R4138C, D

NOTE: Italics denote special 8HJlications

NORMAL OPERATION

TO START­

" terminal , a The lan(5)

larminal L 1: the plug-in amplifier is 8f\o

ergized

" terminal b The alarm 115 energized, bU1 may be

('tHough the alarm silaneing switl:hl, "

-turned off by opening the alarm si!enc­

,

"'""' • app"ed

" terminal 18 ,

open eu1on'lalicalty.)

b • appfled

" terminal 17 tI The purge perod belilins: the lan(s)

~gh the high fire irrtBr1ock) and to

Pow"

lhe mobr ofltle pur~e timer (through bU!l19d fuel and fuel vapor

PT1): 1he purge timer starts

c At the end 01 lhe preset time PT1 , Relay 1 R pulls In: 1 R1 closes to bypass

ctJses, IlPPtyinll power Ie terminal 6 applied Ie the purlle timer (If power is

(Trom terminal L1); the PURGE COM- removed In:m the pur'ile timer, it will

5 Push In the START button and 5 e ~er is applied Ie the i'ilniOOn trans· 5 a Tha i~nrtion transformer Is 9n9r~lZall

statkJn).

shutcbwns when not using

a purge liry'let, wait at lea$!'

minal 6 (II1rou~h the low lire start InlBr­

(1l 1K1 ebses applyin'il power to tur· , (1) TI"MI pilot vllive (or 1st sta~e oil

minai'S tro-n terminal 3 valve) • ener~lled The valve

opens and the pilol: (or 191 sta'ila Oil burner) Is I~n~ed

(2) Jt the pilfJl/lnlc lumper wi/1l I'!~s been

clipped fr:T 8 continurxJs (sr~ng)

piJfJl app/iC81ion, the tfame derec­

rion circUit fO the amp/if/Sf is com-­ pleted

(2l 1K2 closes

be'ilins heatin'il (tty autJtransfonner action of 1K thf'OU'ilh 1K3 and 21<2)

,h hea""

d If 8 C7012E cr F PurpJe Peeper U/tfit-­ pJiffet"Js used, power is applied from ter­

d If an Rrn7C DpIarric Self ChecJc Am­

vir:itJt FlsmtJ DBtacta (NitI'! seIf-eheck· rrifllll 7 t!roUgl'! Itle Jumper to trJm"inaJ Ing feature) is used, the shtmer is ener·

13, t!roU¢ the sr:iid "'are swircfl in the gized.

81tfJIiffet" (between ampli~B>' tfJi"trlnaJs

16 fIftd 17), 10 ttrrTinaJ 12

••

SEQUENCE OF OPERATION FOR THE R4138C 0 (Continued)

NORMAL OPERATION (cOflrinued)

None • The "arne detector detects the nlllT!8 lor llrt stage oiIl1ame) .""

r When the llama is detected relay 2K pull, in

~m8f contact PT2, low nre stan interbck START slam, and inter­

nal jumpel" Power will be applied t:I terminal 7 {tmm terminal 3 tt1rcugh 2Kl ID tenninal e, and tI1rough tI1e

STOP stillion and alarm sileJ'ICing

!Witchl tJ tvJld in relay 1K (unl", Ih8 limb open the STOP button il

occurs

Ing

(3) 210 cloS85, applying power lD tar· (3) The aubnatic main fuel vaMl(a) jljI

1Kl) Relay 3K pulls in and the the main burner is ignited The

sys-FLAME ON (WHITE) IlImp Wghts lern is in the run conditbn (If II

mat1lJ8Ify opened vahe i, usBa', fhe

main l:IUmet will not be igrittKi unrif

step 7 is compleuKf.'

, When relay 3K pulls in­

terminal 15

ing 110 Relay 11< can pull back in after e fT'OTIenlary power failure if

31< is still pulled in

PI 310 opens, rel'TlOVing _, 18 Th FLAME power fn:m OFF P} Retay 1R drops out and 181 opens

'n" '''"'''.

rerroving power fn:m terminal 5

The PUAGE COMPLETE (GREEN)

self-checking system is used).

bullon

7 Normal operetion

7 Open manual main Iw/ valve(s) 7 The main burlJ8f is igrrlfKi Too system is

TO SIOP'

hold it in until the FLAME OFF b Relay 11< drops out lKl operul re- b The pilol valve (or lsi stage oil valve)

c When relay 31< drops oul­

(2) 310 ck:ls&6: ltle FlAME OFF (REO) (2) None

drops out

startup

9 Power ~ retro'tIed from tel'min4l:9 1S end 9 The alarm is

9 Open the alarm silern:ing svwiIch

15

10 Power is rllr1'DWd from tel'miMIs L 1 and '0 The lan(9) stipe end the systIlm is de­

10 Open Ihe masler swilr::h

3 The plug n amplifier is de-energized 808I'"glzed

,,"

SEQUENCE OF OPERATION FOR THE R4138C, D (Continued)

SAFETY OPERATION

Safe Stan Dleck-A flame, or a condi· Raley 2K puns In when the name (or flame- The system cannot be started unm the con· tion simulating a name, is present be- simulating condition) is detected Contact ditiol'l is

inrJ a.cootinuous (st8flding)

, K1 stays open; no IlOM'I' can be ap­ • The pilot valw (or 1st stage oil valve) and

• plied D tlIrminals 19 and 20 the automatic main fuel vatve(s) cannot

main closed The FLAME OFF (RED)

lamp remains on The PURGE COM·

PLETE (GREEN) lamp may also cane

No name is detected so relay 2K does not The system c~ be started The ignrtion

The pilot (or 1st stage oil buma" is not

START bbltlDn is released

(lockout II'I'o'itc:h heater) heats until !he The lockout switch must be manually

re-lockout switch 1I1ps (If the START button set to try to restart !he syslem

is held in longer !han the 'Ockout switch timing)

a lS1 opens and relay 1K drops out a The pilot valve (or 1st stalle oil valve)

can-applied to 18nTIinaJ 20

, Relay 3K cannot pull in; 3K1 and 310 , The slerm remains enerllized not be energized,

(RED} lamp remains on

to restart the system,

a When the START button is released, not bypassed When the START but­

2K1 stays open: the START station is

the ignition transtormer is de-ener·

fn:m terminal T

b Relay 1K drops out end 1K1 opens, b The pilot valve (or 1st stage oil valve)

System shutdown occurs period

NOTE: Safely operation is the same if

• The pilot vlllve (or 1st stall~ oii valve) and the mllin burner is rxrt ig nired in a • 2K1 opens, removinll power fn:m termi­

the automlltic mllin luel vsive(s) are system w;th an interrupted pilot

de-nsls 8 and 7 Relay 1K drops out and 1K1

(obtained only by

opens, removing JXlwer from terminals

lamp goes out

• Thll alarm is energized

The FLAME OFF (RED) lamp lights

• Relay 3K drops out; 3K1 and 310 close

The system shuts down All valves lire

15 All indicator lemps go out and all relays energized, and the valves c!osB The IIlarm drop out 3K1 closes, applying power 10 ler­ is energized

minal16

190

-~.~ -SEQUENCE OF OPERATION FOR THE R4138C, D (Continued)

SAFETY OPERATION (continued)

Momentaty power "fsHure

B4138C;

Power ~ r9IT'QYed from all tanninals aN lndl­

calor lamps go out and all r8l6y, drop out

llill&

Power is rerooved Irem all terminals all indio calor lamps go out, and aU relays except 3K

drop out The charge on capacitor Cl will

hold in 3K tJr about 1 second

• It poWllf' is restored before 3K drops out end before lila plot flame (or 1st

stage oil !IamEI) ~ out­

-3K2 will stay cbsed bypassing lK3;

3Kl and 3K3 Will stay open

- rllfey 2K will pUll bacl( in: 2Kl and

2K3 will cbse and 2K2 will open

-the STAAT staliol1 will be bypassed through 2Kl, the STOP statkm, anl:l the alarm silencing switch

- po er .ill be reappliel:l to lerrninal

7

- relay 1K 111 pull back in thrtluOh LS1 ani:! 3K2

- operation Will re!lJm to normal

• If 3K l:lrops OU1 before power is r&­

stored­

- 3K2 will open, so 110 will nat be by­

passed; 3K1 ani:! 310 will cbse

- relay 1K cannot puU back In since

both 110 8Il1:l 3K2 are open

~ 1K1 stays open so 3K cannal puJf beck In

-!he FLAME OFF (RED) lamp win liOh1 when poWllf' is rr.mred

• II the pilot flame (or 1st staOe oU name)

- relay 2K C8Il1WJ1 pu~ back in 80 2Kl stays open

passel:l

- paMll'" will not be respplied b terml­

r.a17

- relay 1K cannot pull be,ck In

- relay 3K willl:lrop out; 3K1 anl:l JIC will close

-lhe FLAME OFF (RED) IM'lp will

light when paMll'" is restJrel:l

The system shut:l down The alarm is aner­

llized wherI power Is restored

• If pc:JYIIer is re:Jlored within 1 second llnd the pilot llama (or 1st stage cil

name) is still burning (1l1e \/lWe must

be sbw cbsino), rormal OPer4OOr1 will

be resumed The aJarm 'l¥ill not be en­

ergi2ed lIthe main burner name hal

gone out, it will be reionifed by the pi­lot nama (Power failure override eir·

cuits may ha~e b be al:ll:lel:l b the pilot valve and me,in vaNe(s) b enS\J{e lt1al they 1:10 not close on a mctr\EIntary power interruption)

• The systBrn ~huts llown All valVes are I:IlHIn«gizel:l, anl:l the ~a'- cbse The alarm is 8I18rO~ed lIltlen PQ't¥er is

FLAME DETECTION SYSTEM'

The naome l:Ietec:tion system falle \fIthi1e Relay 2K canrot pull in when the 9)'SI&'n is Safety sl'w.1l'lSoWn occurs LJx:kout'l¥ill occur the system is turnel:l all or l:Iuri~ the startel:l-sarne OperllOOt'l as it lhe pibt (or it the STAAT bllltCn is hell:l in IongBf than

The name l:Ietection system lails

l:Iur-Ino the run periol:l with the bumBf

tiring

Aelay 2K l:lrop~ out-same operation as if

the name goee out

Safety shutdown «CUI'S,

This sectlon provides I;lBneral Information about this section does not cover all possible maintenance ac­troubleshooting and maintaining Flame safeguard sys­ livlties tllat are req;ired for every system Again, its pur· lems Its PlJrp:lSe is not to allow the service technician to pose Is to help tl'lE! service technician develop ettective perform specifiC troubleshooting q)Elrations, but to help and efficienl preventive mainlenance programs thaI can the technician develop a consistent, analytical approach be applied 10 all installations

to Flame safeguard system troubleshooting Likewise,

T R O U B L E S H O O T l N G - - - ­

Troubleshooting of control and burner system prob­ TABLE I-BC7000 SYSTEM ANNUNCIATION AND

Iem6 is made easier Ihrough the BC7000 MicroCorTlJuter DIAGNOSTIC CODES

Burner Control Syslam self-dla\1lOSlic and 1irst-out annun­

clallon funclions In addition 10 a line voltal;lB alarm termi­

nal (audible armuncialion), the BC7000 Microcomputer

Burner Control System prOVides visual annunciation by

displaying a 3<:ligit alphanumeric code and one or two se­

quence status lig,ts

SELF· DIAGNOSTICS of the BC7000 detect and an­

nunciatel:xJlh external and internal BC7000 system prob­

lems Exlernal faults such.as interlock failure, 11ame

failure, false flame Sib'f\8l, and damper motor problems,

and internal faults associated wllh (he BC7000 chassis,

the PM72Q Program Module, or the flame amplifier are all

reporfed through tl'lE! Multi-function Annunciator Display

FIRST-OUT ANNUNCIATION is aChieved through the

3<:ligit alphanumeric Multi-function Annunciator Display

thaI rep:lrts the cause 01 a safety shutdown, failure to slarl,

or a failure to continue in the burner sequence The cause

of a safety shutdOwn is displayed as an "F" (faulll, fol­

lowed by a 2-digil nurTt:ler The cause of failure to ~ontinue

with the burner sequence is displayed as an "H" (hold),

followed by a 2-digil nurTt:ler SElquence status lights

(LEOs) provide pOsilive visual indication of the program

sequence: STANDBY /power on), PREPURGE, HOLD

IGN TRIAL FLAME ON, RUN, POSTPURGE, and safety

shutdown (illuminated reset bullon) Momentary power

loss erases this annunciation and requires resel Safety

shutdown (lockout) is indicated by the illuminated reset

bullon and an "F" (fault) code followed by a 2-digit num­

ber safety shutcbwn (lOCkout) d&-energizes all loads en­

ergizes the alarm terminal (atter a 1Q second delay) and

requires a rest With this information, most problems can

be diagnosed without axlansive triat-and-error testing

Table 1 shows the codes used to annunciate and dia~

nose system problems with the BC7000 For the Interpre­

lation and possible remedies for each code, as well as

SYSTElol MOLD CODES

M70 _ FlAME SIGNAL OURING STANDeY M73 - OPEN PRE-IGNITION INTERLOCK H74 _ OPEN RUNNING I~ERLOCK

SYSTEM FAULTA-OCKOUT CODES FCQ _ FALSE FLAME SIGNAL DURING PREPURGE

FD, _ MIGM FIRE PURGE SWITCH FAULT FlU -_ PRE-IGNITION INTERLOCK OPENEO OURING PREPURGE

F()oO - LOCKOUT/RUNNING INTERLOCK OPENED DUR'NG FREPURGE

FlO _ FALSE FLAlolE SIONAL DURING LOW FI."E HOLD F11 - LOW FIRE START SWITCH FAULT

F'3 - PRE·IGNITION INTERLOCK OPENED DURING LOW FIRE HOLO

Fl" _ LOCKOUT/RUNNING INTERLOCK OPENEO DURING LOW FIRE HOLD

F30 - PILOT (FIRST STAGE OIL) FLAME FAILURE F31 - LOW FIRE START SWITCH OPENED OURING PILOT TRIAL

F34 _ LOCKOUT/RUNNING INTERLOCK OPENEO DURING PJl OT TRIAL

FJ,S _ PILOT FLAr.lE FAILURIO IN TEST r.lODE F4(J _ MAIN FLAME FAILEO TO 'GNITE

F _ LOCKOUT/RUNNING INTERLOCK OPEN EO DURING MAIN FLAME TRIAL

F~ -_ FLAr.lE FAILURE DURING RUN PERIOO F!l4 _ LOCKOUT/RUNNING Ih'TERLOCK OPENED DURING RUN PERIOD

F70 - FALSE FLAME SIGNAL OURING STANDBY F73 - P~E·IGNlnON INTERLOCK FAILED TO CLOSE Fe' _ INTE~lolrnENT (eOUNDING) PRE·IGNITION INTERLOCK

F82 FB.3 F~} INTERr.lITIENT IBOUNCING) BURNER F8!I, Fe7 CONTROLLEAr Ir.lIT

F80 _ INTERr.llrTENT (BOUNDING) LOCKOuT/RUNNING INTERLOCK

FIlO - PROGRAM r.lODULE FAULT FIl7 _ eYNCH~DNIZATION ILiNE FREOUENCYI FAULT F99 - INTERNAL CIRCUIT FAULT

cOf1l)lete systam troubleshooting and CJ;lElrating Instruc­

lions, refer to form 65.()()14 trotbleshooling approach presented below is deslgn&d 10 For syslems without self-dia\1lOStic and annunciation; emphasize the similarities involved in troubleshooting dif· (or for problems tllat are not annunciatedl Ihe I;lBneral lerent types 01 systems

'92

In any troubleshooting situation, il is necessary to con­

sider the entire system-Including not only the burner,

controls, wiring, etc., but also air sUWly, /\Jel sUW1y, and

the condition and characterisllcs 01 the flame Itsel1 In or­

der to cover all areas 01' bUrner operallon, lha

troubleshoOting proceoJre is broken down into a series of

specific sleps

The first general step in approaching a system failure is

to doitermine whaiher Ihe shutdown occurs repeatedly or

at random

difl'Ons in the system that can usually be identified by CJb

servation or by a few simple tests

they are caused by marginal or intermittent condiUons (oc­

cur one time but not the next), they do not always occur at

atime when they can be observed Frequer1tly, the only

methOO of Identifying them is to be present when they oc­

cur and be fortunate enOUQh to see what has h~

Often, a shutdown occurs buttha evidence needed cannot

be obtained TIlis results in the need for repeated attempts

before the correct solution can be found

TIlese two types 01 shutdOwn-recurring and ran­

dom-will be discussed separately, since the procedure

lor identifying the causes of each are somewhat different

Recurring Shutdowns are obviously much better suiled to

solution using a step-by·step procedure

RECURRING SHUTDOWNS

After determining the generall'1?9 at failure, determine

the point In the operating cycle al which trouble occurs,

, and the specific symplom To get this informaUoo and to

determine the proper corrective action, aiways complete

the following seven steps;

STEP 1 - KNOW THE SYSTEM AND

EQUIPME~T

Effective troubleshooling requires a knowledge 01 the

complete SyStem and its normal sequence, as well as the

Indi idual devices and equipment that make l4' the sys­

tem TIle availability of a schemallc diagram of the syslem

is a necessity A written sequence 01' the normal operation

of the SyStem is also desjr~le

STEP 2-ASK OUESTIONS

Usually, Ihe information available on arrival at the in­

stallation consists of a sirrple stalemenl that a burner

shuts down Start by asking all the questions possible of anyone lhat mi~t have some knowle6;)e of what hap­

pened When cbeS the shutdown occur? What part of the CYCle? How lonQ after the startup? Does a shutdown occur following every start? How Is the lightoff?

These are only sarrple questions-the lnformation needed will depend on the Individual situation Be sure the operator 01' the SyStem is contacted and questioned Re­tTlQrrOer, they were present and involved when the shut­down occurred

STEP 3-EVALUATE YOUR INFORMATION Usa Table II, together With your personal experience, to herp evaluate any information you have concernillQ the shutdown The conclusions drawn at this stage only pro­vide an idea of where 10 look tor the exaCI solullon 10 the

prOOlem

STEP 4-MAKE A TRIAL RUN Observe the operation of the burner system through a corrprete cyCle Was each slep of the startup in accor­dance with the design sequence? Did any deviations occur? Did the shutdown occur exactly as described? Did anything else happen? Have any new facts been established?

AlSO refer 10 information on measuring the flatTlQ signal during lest runs below

STEP 5-RE-EVALUATE The re-evaluation of availabie facts can often be made during the trial run Mentaily check the possible causes

and eliminate all except those that could b6 resoonsible for lhe shutdown Remember ,that in some instances, more than one factor may be contributing to the prOblem

and must be considered in the solution

STEP 6-VERIFY THE ASSUMED CAUSE BY A TEST RUN

After determining the a,warent causa(s) at eqJipmenl matltnction, perform a second test run to see if the evalu­ation is cOfree! lithe answer has not been found, a new evaluation must be made that Includes any new In1Drma­tion thaI has been obtained cllrlng the second lest run More than one ra-evaluation lest may be necessary to get all 01' the information needed to positively Identify the

cause(s) 01 lhe Shutdown

STEP 7-CORRECT THE CONOITION(S)

TABLE II-TROUBLESHOOTING RECURRING SHUTDOWNS

To assist In delermining lhe cause of a system shutdown, Ihis tabte lists possible causes and corrective actions for each symptom: For-convenience, lhe lable Is divided inlo sections rapresanling lime perlcxE The problems that could occur during a specific peric:d of the operating cycle are listed in each section If specific information on service of a particular control or piece of equipment is required, refer 10 lhe instructional literature for the particular control

, - - - _ - - - ' - - - I M P O R T A N T - - - ,

Repair or replace all defective comp::lrIents, as necessary

INITIAL STARTUP

A ~nce cbes not

start

1 No JXlMlr

Z L.ockwt (safety) switch tri~

3 Limit switch open (in main JXlwer line or in series with the C(){ltroller)

4 Start or preignition interlock open

5 Process interlock open

6 Wiring open

la O1eck master switch and overload protection (fuse, circuit breaker, etc.) Reset or replace, as necessary

20 Reset- find cause and make necessary repairs

3a Slack damper end switch not made

30 Airflow switch open

3c low-waler-cutoff open

3d Fresh·air dal'11P9r (to boiler room) not open

3e Fuel pressure switch open

31 Other interlocks opErI in JXlwer line

4a Check start or prlHgnition interlocks

sa Check all process controls thaI are interconnected wilh the burner system

6a CheCk wiring for breaks or open splices

FIRST 15 SECONDS AFTER START

B System cbes nol go

10 high fire during

1 Wiring-opens, shorts grounds

2 No JXlMlr at firing rale molor

3 Limit switches in firing rale motor nol made

1 High fire switch open

1, O1eck voltages at the wiring sutbase terminals for firing rate switching

20 Check for JXlwer at T·T terminals on firing rate motor

3a Clean conlacls

1a Check switch

1b AdJlISt linkage

1c Check firing rale motor and its transformer

starfS

2b No airflow Check burner motor (blower) and associated corr-ponenls and circults

2c Plugged air line or filling

194

DURING PREPURGE-AFTER 15 SECONDS-BEFORE IGNITION TRIALS

D Flame relay pulis in

(2) Unwanted flame on flame rod

lb Visible light photocell:

(1 ) Light striking cell

(2) Detecting hot felractory

1c Infrared (lead SUlfide) detector:

(1) Electromagnetic piCkl4) on leads Anchor solidly Install coaxial cable if necessary

(2) Unwanted flame being detected

(3) Detecting hal refractory

(3) Defective sensor (replaCe)

le Flame safeguard control:

(1) Defec/ive amplifier (replace)

la 8l.Irner motor (blower) st~

lb Restricted air passage from air d Jct 10 airflow switch

10 Plugged air line or titling

2a Check interlock

LAST FEW SECONDS OF PREPURGE BEFORE IGNITION TRIALS

F 5eq Jence stq:lS 1 Timer switch on flame sat9lJ lard

control set al TEST

la Set switch 10 NORM lXlSilion

2 low fire switch open 2a Check switch

2b Adjust linkage

2c Qleck tiling rate controller (broken polentlometer)

2d Check firing rate motor and its transformer

G No ignition spark 1 No power 10 19lilion transformer

2 HiQh voltage Insulator(sj faulty

3 Ignition elecnode spaf1( gap selling

ta Leadwires cpen, grounded, or not prcperly connected; insulation damagecl

lb Flame saf9lJ lard control not providing power

lc Flame safeguard control recycling

28 Cracked

2b Covered with soot, dir1, or mOisture-causing a shor1to ground

Ja Clean the electrodes

3b SpaCing incorrect-too wide or shorted

3c E!&ctrodeS not prcperly mounted

(cOI1t1nued on IMxt parle)

PROBLEM POSSIBLE CAUSE CHECK

G.(conli~ 4 Ignition transformer failure 4<1 High voltage grOi,lnded

4b Transformer defective

H No pilot flame

-1 No fuel sLWly

.2 Pilol valve inoperative

1a Manual pilot shutoff alva should be wide open 1b Fuel line plugged

1c Low or high gas pressure switch open-adjusl pilot

gas pressure regulator

23 No power at flame safeguard control terminals 2b Incorrect or broken wiring

2c Din in valve, or orifice plugged

2d Faulty actuator or valve

I Flame flOl detected

(llame relay does

no! pUll in)

1 Flame detector (general) 1a Dirty lens, filter, or viewing window

1b Dirt in sight pipe

1c Dirty cells

10 Loose cell

1e, Detector moved to poor location

11 Sighting of detector shifled

19 Delector overheated

1h Low or unstable flame signal

1i Defective detector

2 Fire condition 2a smoky fire

2b Fire pallern changed (Ufled or deflectad')

2c Flame adjustment too lean

3 Wiring 3a Poor connection between burner Qround and flame

safeguard control (Run separate ground wire.) 3b Loose connections

3c Excessively long flame detector laadwires

3d Water in condutt with flame detector leadwifes

Sb Ig'lition interference (SLblraCtive)

St Inadequate grOUnd area

5d Irrprcperly tocaled in flame

59 Broken flame ro::l

6 Infrared (lead sulfide) detector Ga Magnetic piCkup ()(l leads (Should be shielded and

anchored to prevent free vibration or swinging.) fib Defectlve cell

I 7 Ultraviolet detector 7a Excessive vibration (can loosen components in

C7012 types.) 7b C7012-faully electron lube(s)

8 Faulty flame signal amplifier Ga Replace (if a plug-in type)

196

DURING THE MAIN BURNER FLAME·ESTABLISHING PERIOD

J Main burner does

not light-detective

pilot

1 Pilot flame too small ("soft pilot") la Pilot air vents Clogged

lb Blower inlet clogged

lc Brower housing dirty

ld Blower fan dirty

le Pilot air line dirty

H Blower not running

19 Excessive pilot fuel (ori11ce enlarged)

2 Pilot outage 23 loose connection to pilot valve

2b Main burner air SlWIy blowing out pilot

2c Pilot gas vatve partially closed

3 Pilot not adjusted prcperly 3a Adjust air-fuel ratio

3b Adiust pilot position so 11ame will ignite main burner

K Main burner does

not light - improper

4 Pilot size shrinks 4a Pilot line tap on main fuel line is downstream of

main pressure rSQulator (ShoUld be upstream with separate regulator if one is needecl.)

1 Manual main fuel shutoff valve closed

la Open it

fuel supply

2 Safety shutoff valves not opening 2a No power at actuator or at valve terminal on llama

2b Valve stuck in closed p::lSition

2c Defective valve or actuator

2d Check gas pressure switch (see causes 4 and 5)

3 vent valve cpen 3a Power at valve actuator

3b Valve stuck open

3c Check for proper operation of valve and actuator

4 Low gas pressure switch open 4a Check location of low gas pressure switch in gas

line May open when main gas valve closes

4b Adjust gas pressure regulator

5 High gas pressure switch open sa A pressure regulating valve that does not close off

tight will allow line pressure to build up ahead of the main valve Opening the valve allows excess

pressure in line

Sb Adjust gas pressure regUlator

6 Improper air·fuel ratio Ga Adjust as necessary

6b Check burner motor (blower) cperation

7 Low fueltemperalure (oil) 7a O1eck temperature of oil from oil heater (heavy

oils)

7b Defective oil temperature control

7c Defective wiring

8 Faulty fuel system Ba Fuel line downstream from main fuel valve is too

long-requires eltCessive lime to get fuel to the burner

Bb Plugged or dirty fuel line

8c Out of fuel (Oil)

Sd Low atomizing steam or air prSSSlJre (Oil)

(continued on next page)

PROBLEM POSSIBLE CAUSE CHECK

L Main burner lights,

but QOel5 out

1 Main burner flame nol detected 1a Deleclor has pool' view 01 main burner 11ame

(sightil'lQ plIol but not main flame)

1b Detector shifted

1e Smoke in r:ombustlon eharrber

1d Oil ~apors screening deteclor from flame

2 Imprcper air-fuel ratio 2a Flame unstable-poor shape, quallly or position

Adjust air-fuel ratio

.2b Cheek burner motor (blower) operalion

';­

3 Faulty fuel system 3a Low fuel pressure

3b Fuel spray patlem distone:1

Je Oil lank nearly amply Pump is pullin~ air atter a small inilialflow

3d Cold oil in line belween healef and burner Try a reslan

36 AtomiZing sleam or air SlWly pressure 100 low (oil)

DURING A CHANGE IN THE FIRING RATE

M Flame goes oot

du(lng firing rate

charge

1 P~r sUl+Ily voltage drq:l

2 Conditions in combus:ion charrber

1a AcXjed electriea\ load on jXJWer sU~Iy when lirirg rate changes-check circuilry and cO"Inections_

2a Smoke screen between delector and ftame

2b Change in alr·fuel rallo

2c Change in flame paHern

2d Change in oil spray pattern

2e Reclrculalion ol atornlzedoil

N Flame QOes oul , _ Power sUWly ~ariation " Line ~oltage drop due to on-off switching 01 a heavy

electrical load,

1b Power failure

2 Failure In lhe flame deLeclion 2a Check flame signal amplifier Replace amplifier 'f it

2b Clreck 11ame deleclOr

2c If using a 'lame 100, make sure it is nol louching hot re1ractory AlSO check the tempera lure at its

Insulator - if more lhan SOO F [2f>O C], move 11ane rod to a cooler location

2d 11 using an infrared deteclor, chack for hot refractory saluration-make sure that radiation from hot refraclory does not mask the 11ickering radiation of the flame UseN'

38 Delermine cause(s) and correct the condition(s) 3b It airilow switch Is cpen, check burner motor tb!ov'ler) and i!s associaled componenls and circuitry

3 Limil or interlock op8'ls

~

" Check tor improper wiring or deteriorated lead -ires

4b Check: operalion of the val~e and aclualor

4 safety shutoft val~e closes

5• Clean fuel line

5 Plugged 1I.Je1 line

RANDOM SHUTDOWNS

The same general step-by-step procedure is followed

"when troubleshooting random shutdowns as outlined lor

S',ep 1 - Know the system and

Step 2-Ask

Step

S Slep"6- Verify the assumed cause by a test

When troubleshooting random shuldoVoTlS, slep

2-asking questions-becomes an especlallv important

step since the troubleshooter may nof be able to actually

witness a burner shutdOwn Important questions that

might be asked are:

- Has the startup period been complelely

normal-including pilot ignition and main burner Iightoff?

- Have both pilot and main buHlsr flames been burning

properly? At all firing rates? Does the air-fuel ratio

seem satisfactory?

- How has the flame Signal been? Stable or oscillating,

and at what level? (Be sure to verify during trial runs:

check detector sighting)

- How iong since the burner has been serviced and

what was done? Was the detector lens, f\\ter, viewing

window, and sighting pipe cleaned? Flama signal

checked?

- How 10nQ had the burner been running continuously

when the last shutdown occurred, and what was the

firing rate?

- Was there anything different tram normal when the

shutdown occurred?

- Has any eqUipment been 1~IaCed recently? If so,

what an.:::l why?

- Has anything in the system been changed, r~laced,

or worked-on, no mailer hOw unrelated it may seem?

EXAMPLES: A new bOiler installed in the next build­

ing; another healer or boiler connected to the

same stack or breaching

If the cause Of the problem has not been positively iden­

Ilfied after completing the step-by-st~ trOUbleshOOting

procedures, perform routine maintenance on \he burner

Be sure to clean the flame delector, detector mounl, and

any viewino~ windows Check the detector to be sure it has

not shifted in its mount Clean blowers, air dampers, etc

Check the condmon of the pilot and main burner flame,

and adjust as necessary Perform other routine mainte­

nance checks on the oorner eqUipment as req.Jired Make

a trial (un to be certain that the burner is cperating

correctly

If the problem recurs after the service call, it is best to

connect a memory type tester to the system to monitor

burner operation and plSilively pinpoint the cause of shut·

dovm

LOCKOUT (SAFETY) SWITCH INDICATION The type of failure Indicated by whether the namesafe­guard conlrol is locked out or not dependS on the control design and on the particular awllcation

Some name safeguard primary controls-such as lhe R485-do not have a lockout switch Others-suc:' as the A4138-have a lockout switch that will lock out only on fail­ure 10 ignite Masl automatic primary controls, progam­mars and microcOl'T"Puter systems- RA890, R4795 R4140, A41SO A4126, R4127, R41al BC7QOO-w\U lock out on either failure to ignite or flame failure during the run period

In addition they may be designed to lock out in other circumstances, or they may permil the installer to deter­mine whether a lockout will occur in a given situation The RAB90G primary conlrol, for exal1l'le, will lock out

it a flame-Simulating failure occurs during stancby II is also typically connected to lock out on limit action Olher controls such as some models of the R4140 Programmer, have a special lockout interlock circuH; they wUllock out on the action of critical interlocks but will recycle on \he action

ot other limits Even If a special circuit is not prOVided, criti­callimils may be wired to cut off oorner flame on limit ac­tion, causing a flameout that resulls in tripping the lockout switch

In QBneral, safety lockout will indicate a Shutcbwn that

conditions Exal1l'les or such conditions are:

- Poor f\ame characteristics poor pilot, unreliable igni tion source

- FaUlty flame delection system; dirty lens or sighting pipe, burned off or drCllXling flame rod shifted detec­

lor mount, overheated detector, loose comJXlflents

- Flame signal al1l'lifier failure

- Operation of critical inlerlocks (dependS upon the application)

Shutdowns which do not result in safely lockout are

generally caused by conditions resulting in momentalf power failure:

- Loss of line VOltage

- Bad ~ces or loose connections,

- Worn or damaged wiring

- Opening of noncritical limits (dependS upon lhe

awlication)

On automatIc systems, the flame sa1eguard control will recycle and make a restart allerJ1)t semiautomatic sys­

tems will stqJ and rEqJire a manual reslart

Random shutdowns for the most part may be catego­rized under 3 main headings:

1 Failure to ignite 01' detect the pilot

Z Failure to light or delect the main bUrner flame

3 Flameout after igniling the pliot or maIn nama Shutdowns of types 1 and 2 occur during iQ'lition trials; type 3 Shutdowns occur during the run period Hcpetully, the cperator will be able to say at what point in the cycle the 1ailure occurred 11 not, all possibilities must be checked In Table m, PJSSibl8 causes are grouped under

these 3 main headings

TABLE 111_ TROUBLESHOOTING RANDOM SHUTDOWNS

DURING IGNITION TRIALS P"ROBLEM

A FaHure 10 ignita or

detect the pilOt

CHECK

1 Limit or Interlock open 1a Loose, worn, or damaged wiring

1b Temporary condillon Find and correct the condilion(s) causing the limit or interlock 10 open

2b Worn or damaged high voltage leadwires

Ja Manual pilot shutoff valve parity closed

3b Temporarily Clogged orifice in the pilot valve 3c Temporarily pinched or clogged pilaf fuel line

.:la Air register dirty

4b Air damper loose, causing temporary closing of air register

4c Diny or restricted air passages In the burf'\9r

4d Air s\.Wly line pinched, or temporarily restricted

by dirl or scale

48 Diny rotor, passages or housing in lhe burner motor (blower)

detector - may be te"'lXlrarily open or grounded

Sb Loose flame deteclor-shifted its position so it Cba5n't sighl the pilot flame properly

Sc Dirl on the delector lens, filter, or viewing window,

or in the sighting pipe

50 Temporary hot spot in the combLlstion chamber, causing overheating of the detector

se If using a Ilame rod: intermi\lent vibrations causing flame rod to be grounded; dirty or craCked insulator

S! If using a C7012 detector: power SUJ:Ply 1luctuation

Sg Inlermittent circuit in the flame signal amplifier (replace If it is a plug-in type)

5h Loose component(s) in the flame detector

Ga Too smoky Check ail·tuel ralio

6b Flame patlern changed

6c Change in c~ition of fuel

1a lcx:ls9, worn, or damaged Wiring

1b, Temporary condition; correct it

2a Perform checkS under causes 3 and 4 in section

3 Inadaq.Jale fuel suJ:Ply

B Failure to light the

main burner or 10

detect 1119 main

flame

1 Limit or interlock open

2 Inadequate pilot flame

corroustlon chamber

(continued on neld page)

200

PROBLEM POSSiBLE CAUSE CHECK

B:.(continued) 3 Marginal air·fuel ralio fer maIn

burner

3a Adjust as necessary

3b Check bUrner motor (blower) cperatlon

3c Perform checks under causes 3 and 4 In section

A abOve (for main burner Une and ~al\les)

3d Low fuel temperature (heavy all)

-

4 Main burner flame nof defected-faulty flame detection system

5 Main burner flame not detected-combustion chamber conditions

Perform checks under cause 5 In seetlon A above (for main flame detector)

sa Perform checks under cause 6 in seclion A abo\le

Sb Oil bumers-\lapors intermittently screen the detector from the lIame

DURING THE RUN PERIOD

C Flame goes Out

,

1 Power SUWly fluctuation 1 Line ~oltage drc:p due to on-oH switching of a

heavy electrical load

1b Power failure

2 Limit or interlock open 2a Loose, worn, or damaged wiring

2b Tem!Xlrary condition; correct it

3 Safety shutoH \la!\le closes :la Loose, worn, or damaged wiring

4 Marginal flame signal 4a Unstable flame-adjust air-fuel ratio; check

com!Xlsition of fuel

40 Main fuel line le~rarily clogged or pinched 4c Decrease in air SUWly -perform checks urder cause 4 in sacho.' A abo\Ie (for main burner) 4d Faulty flame 09leclion system -perform checks uncIer cause 5 in section A atxwe (for main flame detector)

48 Smoky corrbustion chamber; check air-fIJel ralio and CCllllXJSition of fuel

41 Oil bumers-\lapors intermittently screen the detector from the flame

prepurge (no flame)

1 Stray currents induced in lIame detector leadwires

1a Shorten the leadwires (l1'IO\le the flame safeguard control closer to the burner)

1b Use Shielded leadwires and ground Ihe shield at the wiring sutbase

1c Run the leadwires alone In a separate cor"'dJit, and groond the cordJit at the wiring $I tJbase

(conrinU&d on flfJxt page)

,-

MEASURING THE FLAME SIGNAL firing rale from low tire 10 hi~ fire and back cbwn and _

while modulating in between (if awlicabJe) Table IV inter­

DURING TEST RUNS

preis abnormalllame signal raadinQS that are Indicative of During IrOLbleshOOling, il Is strongly recommended problems.

thallhe 11arne signal be measured throughouf all test runs

NOTE: To find oul hOw 10 measure the flame signal, refer Flame sit;;Jl31 measurements provide valuable information I.Q the Checkout section of the applicable instruction

on system operation The flame signal should be ctlserved sheet

for the flame safeguard control

from slart~ 10 shutdown, including dJring changes in the PREVENTIVl: MAINTENANCE - - - ­

A prS"venliv8 maintenance program should be estab­ eralion, and actual maintenance procedures

lished for the bumer and lis associated oquipmenl 10 en­ Whenever a service technician is engaged in either of

sure maximum availability of the burner, PrevenlivB thBSIJ endeavors, they 6hould keep in mind the following maintenance is divided inlo 2 parts-checking system op- • Ten Commancrnents.·

1 Always close all manual fuel valves anlordisconnectthe wiring from all aL1lomatlc fuel valves before starting a checkoL11

of a burner syslem

2 Visually jnspect every combuslion charrt>er and assure YOL1rsetf that lhere is no accumulation of combustibles before allempting to start a burner system

4 Never p JSh in relays (unless the manufacturer's inslruclions tell you to)

S Nevar permanently hold In relays wllh rul:lber bands, slicks, or other devices

6 Never change the 10ckd\Jt (safety) swllch liming of a flame safeg ard control If lhe system is locking oul, cure the dis­

ease, not the sy~om

7 Never permanenlly jumper or bypass any safety interlocks or limit switches, This is extremely dangerous

8 Conducl a Pilot Turndown Test on every new iob before putting the burner Into service, and periodically thereafter

9 Conducl all required Salety Shutdown Tests (inCluding a Flame Failure Response Test) on every burner al startup and

at least once a year thereafter

10 Regard every burner shutoown as a safety 6huloown until provsn otherwise

CHECKING SYSTEM OPERATION

System operalion should be checked 01"1 a regular ba·

sis Normally a schedule of onc~ a month is satisfactory, but this may be riloc:Iifled depending on the operating con­

dition 01 the burner and the Importance of maintaining burner operation In process awlicatlons, et;lElratlon migl'lt

be checked on a conlinuOU! or daily baSis, Accurate records should be kept on all Cbservalions

By corrparing performance wllh records of past condi­

tions, potentially trOUblesome ChanQBS can be identified and corrective Slaps taken

FLAME SIGNAL MEASUREMENT

"The flama signal is the most important Indlcalor of 1lamecondition A drop In the Ilameslgnal, or a shift from a steady (stable) to an unsteady reading, indicates the need

tor corrective action to avert a 6hulOOwn Ideally, the flame Si "al should be checked for all of lhe following conditions:

a During prepurge (A flame siQnal during prepurge indicates a Slray current Induced in the leadwires, a component failure simulating a flame, response 10 hoi refractory, or an unwanted flame present In the combustion chamber This signal must be eliminated.)

b Al the beginning of Ignition Trials with only the igni­tion on (A flame signal indicates response to the ig­nition spark and must be elimlnaled.)

c Pilot wllh eleclric ignition on

d Pilot with eleclric iQnltlon off

e Main burner flame and pilot oolh on

f Main burner flame on, pllol off (interrupted pilot) Measurements d and f (pilol alone and main burner flame alone) are particularly useful as indicators of general system condillons Table IV liSts corrective aclions for ab­normal flame signal readinl;J>

CONDITION OF THE PILOT AND MAIN BURNER FLAMES

"The general condition-hard, medium, or soft-ol ooth pll01 and main burner flames shOUld be checked On mOC1Jlaring burners, main flame conditions should be cb­S9NecI throughout the full 1Iring range Any awarent Change in lhe air-fuel ralio when the firing rale changes should be investigated On mUltiple stage burners, the flame should be checked at each firing rate It is possible thaI there will be a momentary change In the flame quality resL1l1ing In a very short smoky period as the burner goes

from one slage to anolher This can usually be ignored If the fire recovers to a clean condition promplly

202

(more than 1/2 micre>arT1J)

when ignition is turned off

and only the pilot is on

D Unsleadi (unstable), or

less than the minimum

acceptable current (when

measuring (he pilot alone,

the main burner flame

alone, or bolh 10000therO

NOTE: Flame signal

requirements vary:

Consult the label on the

plug-in flame signal

amplifier, or the CheckOut

seclion 01 the Instruction

sheet 'for lhe flame

sa1ElQJC!rd control

TABLE IV-INTERPRETATION OF FLAME SIGNAL READINGS

DURING IGNITION TRIALS ABNORMAL

1 (continued)

2 Flame-simulaling componenl failure

3 Flame deteclor responding

to hot refractory (rectifying photocell or in1rared detector)

4 Unwanted flame in combustion chamber

1 Flame deleclor responding

to ignitiO/l spark (ultraviolet detectors)

1 Iglilion interference (flame reds)

1 Unslable flame

1d Keep the exposed wires at the ends of the shield or conduit as short as p:>ssible, and lwist them before making connections

le Anchor leadw'ires and conduit at close intervals to avoid noise pickup due 10 vibrations

23 Check flame signal amplifier: replace if defective (plug-in type)

2b Check flame detector; replace i1 defective

3a Add orifice ahead of cell to restrict viewing area 3/) Resighl detector at a cooler, more distant part ot the comoustion chamber

3c Inlrared detector: lengthen the sighting pipe or decrease the pipe size (diameter)

4a Correct the condilion(s} causing the flame

'a Resight lhe detector farther away from the spark or

lb II may be necessary to construcl a barrier 10 shield

lhe spark from the detector

lc Continue adjustmenls until the flama signal due to lhe spark is less lhan 1/4 micr~

1a Make sure there is enough grOlind area

lb Be sure the ignition electrode and flame roo are on q:;p::lSile sides of the ground area

lc Check for correct spacing on the ignition electrode: ,6,000 voll systems~ 1/16 10 3132

ld Make sure the flame rod and i",ilion teadwlres are not too close 10000ther anywhere; replace ant worn

or damaged leadw'ires

le If the problern cannot be eliminated, you may have

to ctJar"9! to an ultraviolet nama delec\ion system

la Adjust air-fuel ratio

lb_ CheCk burner motor (blower) operatlm

lc ~just pressure reg.Jlators

ld Make sure manual fuel shutoff valves are wide q:l9I"I 1e Check fuel line- it may be dirty or pinched

1f Clean the air register, air supply line, air passages,

and blower

lQ Q1eck thaI the composition of the fuel has noe changed

1h Oil burners: adjust oil spray pattern; increase fuel

lerrperature (heavy oil)

(conlinUfld on non page)