User Guide

Field Service Checklist
23
© Copyright 2007, Maxitrol Company. All Rights Reserved.
Observed Problem: Possible Cause: Remedy:
H.
Erratic or pulsating
ame, continued.
2. Erratic air patterns
or improper
TS194(Q) location.
2. Connect test
resistor as
described in step
2 of Preliminary
Circuit Analysis
(pg. 27). Set
point temperature
to process
temperature being
displayed.
If the ame
is steady, the
TS194(Q) should
be moved.
3. Wiring is run next
to high voltage
switching circuits
causing induced
voltages.
3. Temporarily wire
MP2, TS194(Q)
and modulating gas
valve externally
and observe
heater/equipment
operation.
If smooth operation
results, isolate
effected wiring from
source of induced
voltage.
4. Faulty amplier
or erratic voltage
supply.
4. With DC voltmeter
connected (per item
2 above) and locally
connected (per item
3 above), observe
D.C. voltage
across modulator
terminals.
If erratic or unstable
D.C. voltages are
obtained, the MP2
may be faulty.
Replace. If erratic
operation continues
after replacement,
consult Maxitrol
Company.