EngA DJM3

A DJM3
IOM-17 26 of 27 Mar 99 R3

HEATOPERATIONFLOWCHART
 MainSupplypower‘ON’
 ServiceSwitch‘ON’
 Firealarmcontact‘CLOSED’
 24VaconT1,T2
 24VaconFS,HS
Heatcall
light’ON’?
PPlight
’ON’?

Heatcall
light’2SEC
FLASH’?
Noheatcall
Restore24Vac
to‘HS’
Anylights
Flashing?

Indicates
possible
lockout

10Vdcon
terminals
‘
O
’
or
‘
G
’
?
Combustion
fanstarted?

Pre‐Purge
light‘2SEC
FLASH’?
FaultyDJM3

Faultycombustionfan
 Nooutputfromterminal
’CB’
SpeedSensor
Problem
Combustionfan
runningwith5
Vdcacross
terminals‘YS’and
DJM3fuse
failureorfaulty
DJM3

Turnover
magnetor
replace

If0or10Vdcacross‘YS’and‘G’
withCombustionfanrunning,
replacespeedsensor
Ignition
Enablelight
‘
ON
’
?
Unitstuckin
Pre‐Purge

PowergoestoIgnition
Control,burnerwill
light.OnceDJM3
receivesfeedbacksignal,
firingratewillmodulate.
Normalo
p
eration
YES
YES
YES
NO
NO
NO
YES
YES
NO
NO
YES
YES
YES
NO
NO
NO
YES
NO