Burnham K2WT Residential, Installation, Operating And Service Instructions

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XIV. Troubleshooting
(continued)
Soft Lockout Codes Displayed
F. Troubleshooting problems where a Soft Lockout Code is displayed.
When a soft lockout
occurs, the boiler will shut down, the display will turn red and the “Help” button will “blink”. Select the “blinking”
“Help” button to determine the cause of the soft lockout. The boiler will automatically restart once the condition
that caused the lockout is corrected.
Lockout
Number
Condition Possible Cause
2
Boiler Safety Limit
Open
Boiler Safety Limit wired to terminals J6-1 or
3 OPEN:
• External Limit.
• Optional LWCO
External Limit:
• Water temperature is higher than External Limit setting. See “Hard
Lockout 4” for additional information.
• External device not used and jumper not installed.
• External Limit device is defective.
• Loose wiring to limit device
Optional Low Water Cut Off (LWCO)
• If yellow light on LWCO is on, system is low on water. Ensure air vent
is unobstructed and properly functioning as a blocked air vent can
result in low water indication.
• If neither yellow or green light on LWCO is on, check LWCO harness.
3
Boiler Safety Limit
Open
Blocked Flue/Inlet Switch wired to terminals
J5-1 OPEN
• Blocked Flue/Inlet Switch contact open - check for blocked flue/air intake.
NOTE
Blocked Flue/Inlet Switch Special Note
Before a call for heat the air pressure switch is closed. When there is a
call for heat with a blocked vent the air pressure switch will open (due to
excessive pressure of the blower against a blocked flue pipe) after the blower
starts. The control stops the start sequence and stops the blower. After the
blower stops the pressure switch re-closes and the cycle continues. The
displays shows the cause of trip for only the time the pressure switch is open.
7
Return sensor
(10 KOhms) fault
Shorted or open return temperature sensor.
• Shorted or mis-wired return sensor wiring.
• Defective return sensor.
8
Supply sensor
(10 KOhms) fault
Shorted or open supply temperature sensor.
• Shorted or mis-wired supply sensor wiring.
• Defective supply sensor.
10
Stack sensor
(10 KOhms) fault
Shorted or open flue gas (stack)
temperature sensor.
• Shorted or mis-wired flue temperature sensor wiring.
• Defective flue temperature sensor.
11
Ignition failure
Flame failure after 5 tries to restart. Flame
rod not detecting flame.
• No gas pressure.
• Gas pressure under minimum value shown on rating plate.
• Gas line not completely purged of air.
• Gas valve rectifier switch off.
• Defective Electrode.
• Loose burner ground connection.
• Defective Ignition Cable.
• Defective gas valve (check for 24 Vac at harness during trial for ignition
before replacing valve).
• Air-fuel mixture out of adjustment - consult factory.
• Defective or fouled electrode.
• Blocked vent
• Condensate trap plugged or dirty.