S-Series Technical Manual 53 Cambridge Engineering, Inc.
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem Possible Cause Corrective Action
IX. MODULATING
VALVE DOES NOT
MODULATE;
CONTINUOUS
LOW FIRE
(Continued)
5. Space Temperature Selector
(T244 or TS244/TD244)
a) Short in sensor circuit a) Replace the sensor if the resistance mea-
sure is less than 5,000 Ω for the T244 or
3,500 Ω for the S244 and 1,950 Ω for the
TD244.
6. Remote Heat Adjust
(TD114 or CEI 4175-0-960)
a) Open in the Remote Heat Adjust control
circuit
a) Replace the control if the resistance
measured at terminals 1 and 3 exceeds
12,000 Ω.
7. Multi-Functional PC Board
a) Terminal X has power
b) Defective board
a) Determine power source.
b) Replace board.
X. ERRATIC OR
PULSATING FLAME
1. High Pressure Regulator
a) Vent undersized
b) Defective regulator
a) Enlarge vent piping size or reduce vent
piping length.
b) Replace regulator.
2. Amplifier
a) Hunting
b) Temperature control system out of cali-
bration
c) Defective amplifier
a) Adjust sensitivity control dial counter-
clockwise.
b) Perform appropriate calibration procedure
(pages 29-31).
c) Replace amplifier.
3. Space Temperature Selector
(T244 or TS244/TD244)
a) Induced voltage in field wiring a) Utilize shielded, twisted pair wiring.
4. Remote Heat Adjust
(TD114 or CEI 4175-0-960)
a) Induced voltage in field wiring a) Utilize shielded, twisted pair wiring.
To Next Page
Loading...