Wing Enterprises IOMWDF-1 - Manual (Page 15)

15
Symptom Possible Cause Field Test Remedy
E. continued
F. Incorrect
Maximum or
Minimum
Discharge Air
Temperature.
G. Continuous High
Fire (Electronics
OK).
H. Continuous High
Fire (Electronics
Problem).
I. Incorrect High Fire
J. Continuous
Maximum Discharge
Air Temperature.
K. Burned out
Transformer. No
Voltage to Amplifier.
3. Follow procedures outlined
in “Preliminary Circuit
Analysis” in Section IX.
1. Compare sensed
temperature reading at
TS144 with average
discharge air temperature.
2. Follow procedures outlined
in “Preliminary Circuit
Analysis” in Section IX.
1. Remove bottom plate and
inspect valve and seat.
2. Inspect. Plunger should
be smooth and clean and
operate freely in solenoid
sleeve.
1. Measure resistance per
item C3.
1. Read inlet pressure at valve
using manometer with
heater operating at full fire.
Pressure should be at least
equal to the sum of: outlet
pressure setting and
pressure drop of the valve
plus 1.0” W.C.
2. Read outlet pressure using
manometer and compare
with the pressure stated
on the specification plate.
1. Follow procedures outlined
in “Preliminary Circuit
Analysis” in Section IX.
2. Measure resistance per
item E2.
3. Follow procedures outlined
in “Preliminary Circuit
Analysis” in Section IX.
1. Measure resistance per
item B1.
3. If proper action is obtained,
first check item E2.
Recalibrate if necessary.
1. Move TS144 to location
where average temperature
can be sensed.
2. If proper temperatures are
not observed, refer to
Discharge Air Temperature
calibration procedures.
1. Clean, replace valve and/or
seat if necessary.
2. Clean, or if necessary,
replace plunger
1. If readings are incorrect,
replace the TS144 or repair
wiring.
1. Increase inlet pressure if
possible or change to larger
valve. Consult factory
about possibility of using
special spring to reduce
pressure drop on selected
installations.
2. See Valve Adjustments in
Section IX.
1. If amplifier is proven at
fault, install replacement
amplifier.
2. If reading is incorrect,
replace T244,
TS244/TD244 or repair
wiring.
3. If proper action is obtained,
first check item J2.
Recalibrate if necessary.
1. If proper resistances are
not observed, replace
modulator head or repair
wiring.
Control circuits external to Series 44 can cause burner malfunction. Always check manual valve to be
certain gas is on, and check limit controls for normal operation.
3. Incorrect space
temperature calibration.
1. Improper TS144
location.
2. Incorrect discharge
air temperature
calibrations.
1. Foreign material
holding valve open.
2. Plunger jammed.
1. Open circuit in TS144.
1. Inlet pressure too low.
2. Incorrect outlet
pressure adjustment.
1. Faulty amplifier.
2. Open circuit in T244
or TS244/TD244.
3. Incorrect space
temperature calibration.
1. Short in modulator coil
circuit.
TROUBLESHOOTING GUIDE
Series 44 Room Temperature Control continued Reproduced with permission from Maxitrol® Company