Single Gas Instrument Service Manual
Page 16
Bacharach, Inc.
Instruction
0019-9166
Symptom
Cause
Remedy
Sensor connections loose
Motor has excessive arcing in
its carbon brush/commutator
interface causing RFI
Chamber assembly screws loose
Fan-blade Assembly loose
Inlet and/or outlet port(s)
blocked
Motor connections loose
Motor defective
P.C.B. defective
Bouncing display > ± 3 counts
Very little (<0.25" H2O) or no
draft indication on manometer
dead headed into instrument
Check Sensor connections.
See Fig 2-2.
Run Motor for at least 3 hours
to wear away arc spots. If
display still bounces, replace
Motor Assembly. Refer to Sec-
tion “2.6 Chamber Assembly
Servicing.”
Tighten screws. Refer to Sec-
tion “2.6 Chamber Assembly
Servicing.”
Open chamber assembly and
ensure that Fan-blade Assem-
bly is mounted on Motor shaft.
Refer to Section “2.6 Chamber
Assembly Servicing.”
Clean ports. Refer to Section
“2.3 Cleaning.”
Reconnect Motor leads. Refer
to Section "2.6 Chamber As-
sembly Servicing."
Check operation of Motor. If
motor is receiving power but
isn’t turning, replace Motor
Assembly. Refer to Section “2.6
Chamber Assembly Servicing.”
Replace P.C.B. Refer to Sec-
tion “2.5 Printed Circuit Board
Replacement.”
