Aerco Modulex MLX-303 User Manual

MC2: 10/03/12 Page 66 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
Figure 10-1: E8 Controller Front Panel Showing Error Code in Display
Table 10-1: Boiler Troubleshooting – PCB Terminal
FAULT
INDICATION
PROBABLE CAUSES CORRECTIVE ACTION
E1:
Thermostat
indicates high
temperature limit
exceeded
1. Temp HI Limit setting is too
low.
2. Faulty temperature sensor.
3. Faulty Water temperature
switch.
4. Incorrect PID settings.
5. Faulty shell temp. sensor.
6. Unit in Manual mode
7. Unit setpoint is greater than
Over Temp Switch setpoint.
8. Boiler Management System
PID or other settings not
correctly setup.
9. No interlock to boiler or BMS
to disable boiler(s) in event
that system pumps have
failed.
10. System flow rate changes
are occurring faster than
boilers can respond.
1.
Check Temp HI Limit setting adjust Parameter to
XXXXXX.
2. Test the temperature sensor and replace if necessary.
3. Test the temp switch to insure it trips at actual water
temp setting.
4. Check PID settings against Menu Default settings in
the Appendix. If the settings have been changed,
record the current readings then reset them to the
default values.
5. Use resistance charts in Appendix C. Measure the
resistance of Shell sensor and BTU sensor at a known
water temperature.
6. If unit is in Manual Mode switch to Auto Mode.
7. Check setpoint of unit and Temperature Switch;
Ensure that the temperature switch is set higher than
the unit’s setpoint.
8. Check the BMS for changes to PID default values and
correct.
9. If system pump is controlled by Energy Management
System other than BMS or pumps are individually
controlled by boiler, check to see if flow switches are
interlocked to the BMS or boiler.
10. If the system is a variable flow system, monitor
system flow changes to ensure that the rate of
flow change is not faster than what the boilers can
respond to.
Error Codes are
Displayed Here

Aerco Modulex MLX-303 Specifications

General

Brand	Aerco
Model	Modulex MLX-303
Category	Boiler
Language	English