Ingersoll-Rand M952V060BD36AB, Service Facts

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Service Facts
M952-SF-4
2 Flash Fault LED
Cycle power to
furnace and call
for 1
st
stage heat
Does gas
ignite?
YES
NO
Is outlet gas
pressure
~1.7"WC (NG)
~6.0"WC (LP)
YES
Do all burners
ignite within 5
seconds?
Check igniter
position and
correct if needed.
Check operation
Adjust manifold gas pressure to
~1.7"WC (NG)
~6.0"WC (LP)
Check operation
NO
Clean and align
burners correctly.
Check operation
NO
YES
Measure flame
current. Is flame
current less than 1
micro-amp?
(3-4 ua = Normal)
YES
Is flame sensor
located
correctly?
Replace flame
sensor. Check
operation
YES
Correct and check
operation
NO
Flame sensor is
good
NO
Is minimum
outlet gas
manifold
pressure
maintained?
Does inlet gas
pressure drop
more than 2"
WC
NO
Correct inlet gas
pressure
Check operation
Replace Gas Valve
Check operation
YES
Disconnect electrical
power to furnace.
Connect manometer
to oulet gas pressure
connector
NO
Cycle power to
furnace and call
for heat
YES
DEFINITION
RETRY Lock Out = 3 unsuccessful tries for
ignition within a single call for heat
Flame has never been sensed
RECYCLE Lock Out = 10 recycles within a
single call for heat.
Flame is sensed & then lost
Disconnect electrical
power to furnace.
Connect manometer
to inlet gas pressure
connector
Is inlet gas pressure
above 14" WC or less than
nameplate minimum ?
NO
Correct inlet gas
pressure
Check operation
YES