Service Manual
3 Troubleshooting (continued)
Table 3G (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface
FAULT | DESCRIPTION |
| CORRECTIVE ACTION | |
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| • Check the wiring connections to switch. Wires should | ||
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| be connected to the common and normally open | |
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| terminals. |
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| • | Remove switch and check for blockage in the orifice. | |
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| • Vent/air intake lengths exceed the maximum allowed | ||
Blower Proving |
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| lengths. Refer to Section 2 - General Venting of the | |
|
| Crest Installation and Operation Manual for | ||
Switch Open 2 |
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| proper lengths. |
|
(will require a manual |
| • Check for obstruction or blockage in | the vent/air | |
reset once the condition | Pressure switch contacts are open. |
| intake pipes or at terminations. |
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has been corrected. Press | • Inspect the burner. Reference page 34 of this manual | |||
the RESET button on the |
| |||
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| for removal and cleaning procedures. | Replace if | |
display to reset.) |
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| ||
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| necessary. |
| |
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| |
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| • Verify combustion air blower 2 is operating. Replace if | ||
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| necessary. |
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| • Inspect the heat exchanger. Reference page 35 of | ||
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| this manual for removal and cleaning procedures. | |
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| • Faulty pressure switch. Replace switch. | ||
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| ||
Burner Supply |
| • Inspect the combustion air temperature sensor and | ||
Temperature |
|
| associated wiring. |
|
Differential | Combustion air to burner 1 temperature | • Measure the resistance of the combustion air | ||
(will require a manual | is higher than combustion air to burner 2 |
| temperature sensor and compare to Table 3E on | |
reset once the condition | temperature or vice versa. |
| page 38 of this manual |
|
has been corrected. Press |
| • Replace the sensor if necessary. |
| |
the RESET button on the |
| • Verify that the vent / air intake pipes | are properly | |
display to reset.) |
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| installed and that there are no obstructions. | |
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| ||
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| • Check if the vent backflow preventer is installed for | ||
Burner Supply |
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| boilers commonly vented. |
|
Temperature |
| • Check if the vent backflow preventer is stuck open | ||
High 1 |
|
| while the unit is off. |
|
(will require a manual | Combustion air temperature is very high. | • Inspect the combustion air temperature sensor and | ||
reset once the condition |
| associated wiring. |
| |
|
|
| ||
has been corrected. Press |
| • Measure the resistance of the combustion air | ||
the RESET button on the |
|
| temperature sensor and compare to Table 3E on | |
display to reset.) |
|
| page 38 of this manual. |
|
|
| • | Replace the sensor if necessary. |
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|
|
| ||
|
| • Check if the vent backflow preventer is installed for | ||
Burner Supply |
|
| boilers commonly vented. |
|
Temperature |
| • Check if the vent backflow preventer is stuck open | ||
High 2 |
|
| while the unit is off. |
|
(will require a manual | Combustion air temperature is very high. | • Inspect the combustion air temperature sensor and | ||
reset once the condition |
| associated wiring. |
| |
|
|
| ||
has been corrected. Press |
| • Measure the resistance of the combustion air | ||
the RESET button on the |
|
| temperature sensor and compare to Table 3E on | |
display to reset.) |
|
| page 38 of this manual. |
|
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| • | Replace the sensor if necessary. |
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