MC2: 10/03/12 Page
68
of
90
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
•
Ph: 800-526-0288
GF-115-H
OMM-0083_0B
Modulex MLX Series Gas Fired Boiler System
Operation and Maintenance Manual
Chap 10:
Troubleshooting
FAULT
INDICATION
PROBABLE CAUSES
CORRECTIVE ACTION
8.
Worn flame detector
9.
No spark from Spark
Plug
10. Defective Ignition
Transformer
11. Defective
Ignition/Stepper
(IGST) Board
12. Defective SSOV
13. Defective Differential
Pressure Regulator
14. Carbon or other
debris on Burner
11. If 120VAC is not present, the IGST Board in the Control
Box may be defective. Refer fault to qualified service
personnel.
12. While externally arcing the spark ignitor, observe the
open/close indicator in the Safety Shut-Off Valve to ensure
it is opening. If the valve does not open, check for 120VAC
at the valves input terminals. If 120VAC is not present, the
IGST board in the Control Box may be defective. Refer
fault to qualified service personnel.
13. Check gas pressure readings using gauge or manometer
into and out of the Air/Fuel Valve to ensure gas is getting to
the burner.
14. Remove the burner and inspect for any carbon or debris.
Clean and reinstall
E6:
Outlet water
temperature
as detected
by the
heating
sensor (SR)
exceeds
203°F.
Immersed
probe
Water is not flowing
properly. It’s detected
when the local Flow
Sensor temperature is >
203°F (95°C) and cleared
when it’s < 80°C (176°F).
Verify that the water circulation is flowing properly.
Note: By opening the flap of the E8 and pushing the pushbutton,
an indication of the number of degrees that the burner is in error
is provided.
E10:
Local PCB
failure – BMM
Board
Boiler not seeing
information from Boiler
Management Module
PCB.
Check connections. If fault persists, contact qualified Service
Personnel.
E11:
Residual
flame at start
1. shorted flame rod
2. SSOV not fully
closed.
1. Annual Maintenance: Clean the flame rod
2. Check open/close indicator window of Safety Shut-Off Valve
(SSOV) and ensure that the SSOV is fully closed. If not fully
closed, replace the valve and or actuator.
Close gas shut-off valve downstream of SSOV. Install a
manometer or gauge in a gas test port between the SSOV
and the gas shut off valve. If a gas pressure reading is
observed replace the SSOV valve and or actuator.
E12:
Outlet
temperature
sensor failure
(SR)
1. Loose or broken
wiring.
2. Defective Sensor.
3. Incorrect Sensor.
1. Inspect Outlet Temperature sensor for loose or broken wiring.
2. Check resistance of sensor to determine if it is within specification.
3.
Ensure that the correct sensor is installed.
Table 10-1: Boiler Troubleshooting – PCB Terminal (Continued)