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107774-02 - 4/18
XV. Troubleshooting
(continued)
G. Troubleshooting problems where a Hard Lockout Code is displayed.
When a hard
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 Hard Lockout. Once the condition that caused the lockout
is corrected, the boiler will need to be manually reset using the Reset button on the “Active Fault” display or
located on the Control.
Hard Lockout Codes Displayed
Lockout Number
Condition
Possible Cause
4
Supply High Limit
Control supply sensor detected
temperatures in excess of 210°F.
• Heating load at time of error was far below the minimum firing
rate of the boiler.
• Defective system circulator or no flow in primary loop.
• Defective boiler circulator, no flow or insufficient flow in boiler
loop.
• Control system miswired so that the boiler operation is
permitted when no zones are calling.
6
Stack High Limit
Control Flue gas (Stack) sensor
detected temperatures in excess of
214°F (101°C).
• Heat exchanger needs to be cleaned.
• Boiler over-fired.
• Air-fuel mixture out of adjustment - consult factory.
12
Flame detected out of sequence
A flame signal was present when there
should be no flame.
• Condensate trap plugged.
• Defective gas valve - make sure inlet pressure is below
maximum on rating plate before replacing valve.
• Plugged drain line in trap.
18
Light off rate proving failed
Blower is not running at Light-off rate
when it should or blower speed signal
not being detected by Control.
• Loose connection in 120 VAC blower wiring.
• Loose or miswired blower speed harness.
• Defective blower
19
Purge rate proving failed
Blower is not running at Purge rate
when it should or blower speed signal
not being detected by Control.
• Loose connection in 120 VAC blower wiring.
• Loose or miswired blower speed harness.
• Defective blower
20
Invalid Safety Parameters
Unacceptable Control Safety related
parameter detected.
Safety Parameter verification required. Contact factory.
21
Invalid Modulation Parameter
Unacceptable Control Modulation
related parameter detected.
Reset the control.
22
Safety data verification needed
Safety related parameter change has
been detected and a verification has
not been completed.
Safety related Control parameter has been changed and verification
has not been performed.
23
24VAC Voltage low/high
Control 24Vac control power is high
or low.
• Loose connection in 24Vac VAC power wiring.
• Loose or miswired 24Vac harness.
• Miswired wiring harness causing power supply short to ground.
• Defective transformer.
• Transformer frequency, voltage and VA do not meet
specifications.
24
Fuel Valve Error
Power detected at fuel valve output
when fuel valve should be off.
• Reset the control. If problem reoccurs, replace the Control.
25
Hardware Fault
Internal control failure.
• Reset the control. If problem reoccurs, replace the Control.
26
Internal Fault
Internal control failure.
• Reset the control. If problem reoccurs, replace the Control.
27
Undefined Fault
Undefined Fault
• Reset the Control. If problem reoccurs, replace the Control.
54
Air Proving Switch
Failed to Open
Air Proving Switch Failed to Open
See Soft Lockout 54.
Summary of Contents for K2WTC-135
Page 81: ...81 107774 02 4 18 X Domestic Hot Water Piping continued Figure 10 1 Domestic Hot Water Piping...
Page 89: ...89 107774 02 4 18 XI Wiring continued...
Page 90: ...90 107774 02 4 18 Figure 11 8 Internal Wiring Connections Diagram XI Wiring continued...
Page 101: ...101 107774 02 4 18 Lighting and Operating Instructions XII Start Up and Checkout continued...
Page 142: ...142 107774 02 4 18 XVI Repair Parts continued...
Page 145: ...145 107774 02 4 18 XVI Repair Parts continued...
Page 148: ...148 107774 02 4 18 XVI Repair Parts continued...
Page 150: ...150 107774 02 4 18 XVI Repair Parts continued...
Page 152: ...152 107774 02 4 18 XVI Repair Parts continued 120 121 122 123 124 125 126 127...
Page 159: ...159 107774 02 4 18 SERVICE RECORD DATE SERVICE PERFORMED...