POWER VTX
®
WATER HEATER
33
PV500-68 06/16
11 COMMUNICATIONS AND DIAGNOSTICS
11.1 Indicators
The PIM has three LED indicators to display operational status and to help diagnose system error conditions:
•
Power: Green LED indicating the PIM module is receiving 24 VAC power.
•
Alarm/Test: Amber LED which indicates the PIM is in Commission Test Mode or that a diagnostic alarm (fault)
is present.
•
Diagnostic
Code:
Red LED that is normally off. During a control or system fault condition, this LED flashes the
error codes.
11.2 Alarm Messages – Diagnostic Codes (Flashes)
ALARM
MESSAGE
DESCRIPTION OF ALARM
LED
Flashe
s
MODBUS
CODE #
ID CARD
The ID card is connected to the PIM control board when the system
is initialized for the first time, the ID card selects the control profile to
be used. An ID card error may occur when the original card is
replaced with an incorrect card or has been disconnected from the
PIM control board.
Red LED
ON,
Green
LED OFF
20
INTERNAL FAIL The PIM control board may have failed. Replace the control board if
manually resetting the control does not correct the fault.
Red
LED ON
21
CTL SETUP
FAIL
Try resetting the defaults in the TOOL BOX menu. If unable to
correct, replace the control display
N/A 1
VENT LIM
The vent temperature sensor is approaching the programmed limit.
This will force the burner to operate at a reduced firing rate to
prevent overheating.
N/A 5
AIR FLOW FAIL
During blower purge periods the air flow proving switch is not
closing this circuit. This could be caused by a faulty blower or
pressure switch.
1 9
FLAME FLSE
A false flame signal is usually cause by a leaky gas valve which
propagates a flame after the call for heat cycle has ended. Check for
leakage through the gas valve. If no mechanical cause can be
found, replace flame control.
2 19
FLAME FAIL
Flame failure indicates that during the burner ignition process, the
burner either failed to light or it did light but no flame signal was
detected. If the burner fails to light it is likely that the hot surface
igniter (HSI) is faulty or the burner fuel/air mixture is too far out of
adjustment to ignite. If the burner lights but immediately go out,
check for an inadequate gas supply, faulty gas valve or regulator or
poorly adjusted combustion.
3 15
FLAME LOSS
Flame loss indicates that sometime after flame has been
established and the burner is operating, the flame signal is lost. This
can be caused by a faulty igniter, damaged refractory or combustion
that becomes poorly adjusted as the burner modulates to higher
inputs.
3 16
LOW HSI
The PIM control board is not sensing the correct amp draw from the
HSI (Hot Surface Igniter). This is most likely caused by a faulty or
disconnected igniter.
4 23
LOW 24VAC
The 24VAC supply to the PIM control is below the threshold for
reliable control operation. This may be caused by low voltage to the
heater or a faulty 120/24VAC supply transformer.
5 24