Lochinvar Shield SNA285-125 - Manual (Page 66)

66
13
Troubleshooting
Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater
Interface
FAULT DESCRIPTION CORRECTIVE ACTION
Temp O/Shoot
(continued)
The temperature rise across the heat
exchanger has exceeded the set
parameters for the water heater.
• Verify that the system is full of water and that all air
has been properly purged from the system.
• Verify that the water heater is piped properly into the
heating system. Refer to Section 6 - System Piping
for the proper piping methods for the Shield water
heater.
• Check for 120 VAC to the water heater pump motor
on a call for heat. If voltage is not present, check the
wiring back to the main control board. Replace the
main control board if necessary.
• If 120 VAC is present on a call for heat and the water
heater pump is not operating, replace the pump.
• Verify that the water heater pump is set to the proper
speed or that the pump is the proper size.
Reference Section 6 - System Piping for water heater
pump specifications.
Heat exchanger outlet water temperature
has exceeded the maximum outlet water
temperature.
• Verify that the system is full of water and that all air
has been properly purged from the system.
• Verify that the water heater is piped properly into the
heating system. Refer to Section 6 - System Piping
for the proper piping methods for the Shield water
heater.
• Check for 120 VAC to the water heater pump motor
on a call for heat. If voltage is not present, check
wiring back to the main control board. Replace the
main control board if necessary.
• If 120 VAC is present on a call for heat and the water
heater pump is not operating, replace the pump.
• Replace the main control board.
Parameters
Progr
(will require a manual
reset once the condition
has been corrected. Press
the RESET button on the
display to reset.)
After downloading parameters from a
laptop, the main control board must be
reset.
• Press the ENTER/RESET button on the display
panel.
Blocked Drain
SW
(will retry after 5
minutes. RESET may be
pressed after condition is
corrected.)
The blocked drain switch has detected
excessive condensate build up inside the
unit.
• Check condensate tube from unit to floor drain for
proper installation and obstructions.
• Inspect condensate trap for blockage. Clean if
necessary.
• Check for loose wiring connection at wire harness
plug.
• Bad blocked drain switch. Replace switch.
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