AERCO Innovation (G-14-2265 and above) - Manual (Page 105)

Innovation Water Heaters Installation, Operation & Maintenance Manual
CHAPTER 7 – TROUBLESHOOTING GUIDE
OMM-0078_0L AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 Page 105 of 206
GF-128
Phone: 800-526-0288
PRI: 11/25/2014
TABLE 7-1. WATER HEATER TROUBLESHOOTING – Continued
FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION
LINE VOLTAGE
OUT OF PHASE
1. Line and Neutral switched in AC
Power Box.
2. Incorrect power supply
transformer wiring.
1. Check hot and neutral in AC Power Box to ensure they are not
reversed.
2. Check transformer wiring, in AC Power Box, against the power
box transformer wiring diagram to ensure it is wired correctly.
LOW GAS
PRESSURE
1. Incorrect supply gas pressure.
2. Defective Low Pressure Gas
Switch.
1. Measure gas pressure upstream of the SSOV Actuator(s) with
the unit firing. For both FM and DBB gas trains, ensure it is
between 4.0” W.C. and 14” W.C. (see section 2.10.1).
2. Measure gas pressure at the low gas pressure switch. If it is
greater than 2.6” W.C., measure continuity across the switch
and replace if necessary.
LOW WATER
LEVEL
1. Insufficient water level in system.
2. Defective water level circuitry.
3. Defective water level probe.
1. Check system for sufficient water level.
2. Test water level circuitry using the Control Box front panel LOW
WATER TEST and RESET buttons. Replace water level
circuitry if it does not respond.
3. Check continuity of probe end to the shell, change probe if there
is no continuity.
MODBUS COMM
FAULT
Unit not seeing information from
Modbus network Check network connections. If fault persists, contact qualified
Service Personnel.
PRG SWTCH CLOSED
DURING IGNITION
1. A/F Valve rotated open to purge
and did not rotate to ignition
position.
2. Defective or shorted switch.
1. Start the unit. The Air/Fuel Valve should rotate to the purge
(open) position, then back to ignition position (towards closed)
during the ignition cycle. If the valve does not rotate back to the
ignition position, check the Air/Fuel Valve calibration. If
calibration is okay, the problem may be in the Air/Fuel Valve or
the Control Box. Refer fault to qualified service personnel.
2. If the Air/Fuel Valve does rotate to the ignition position, check
the purge switch for continuity between the N.O. and COM
terminals. If the switch shows continuity when not in contact
with the cam, check to ensure that the switch is wired correctly
(correct wire numbers on the normally open terminals).