Watts Aerco Modulex MLX EXT 1530 - Page 113

Modulex EXT Commercial Series Boilers User Manual
CHAPTER 7: Troubleshooting
OMM-0095_0H AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 Page 113 of 144
GF-139 Phone: 800-526-0288 09/15/2017
TABLE 7-2: E8 Controller Fault Codes (Continued)
CODE DESCRIPTION EFFECT CORRECTION RESET
System Manager Fault – Sensor Defective (Break/Short Circuit)
E 69
E8: F5 – Flow temperature
sensor heating circuit 2.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 70
E8: F11 – Flow
temperature sensor
heating circuit 1.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 71
E8: F1 – Lower storage
temperature sensor
(Buffer).
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 72
E8: F3 – Higher storage
temperature sensor
(Buffer).
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 75
E8: F9 – Outer
temperature sensor (AF).
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 76
E8: F6 – DHW storage
temperature sensor (SPF).
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 78
E8: F8 – Boiler
temperature sensor (KF).
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 80
E8: F2 – Room
temperature sensor
heating circuit 1.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 83
E8: F15 – Room
temperature sensor
heating circuit 2.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 135
E8: F12 – Lower DHW
storage temperature
sensor MF2.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 136
E8: F13 – Boiler 2,
Manifold 2 MF 3.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 137
E8: F14 – Manifold 1,
Multifunction 4.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
E 138
E8: F15 – Room
temperature Hc2.
Check continuity. Use
multimeter to measure sensor.
AUTOMATIC
Communication Fault
E 90
E8: BUS addresses 0 and 1.
The BUS codes 0 and 1
cannot be used at the
same time.
Check addresses
E 91
E8: BUS code occupied.
The set BUS code is
already used by another
appliance.
Check addresses
E 99
E8: Internal failure.
Check E8 settings. Possibly
replace E8.
AUTOMATIC