7)Start the boiler using the lighting instructions on page 49. After the boiler is powered up, it should go through the following sequence.

Sequence

Display

Meaning

1

U.125 or Blank

Checking internal software (power-up only)

2

0.SWT

Boiler in standby. SWT = Supply Water Temp. No call for heat.

(After call for heat from heating thermostat)

3

A.SWT

Self-Check on Start-up

4

5.SWT

Blower and circulator on. Checking for adequate air flow.

5

1.SWT

Prepurge

6

2.SWT

Trial for ignition

7

3.SWT

Flame established. Boiler responding to a call for heat.

8)Upon initial start-up, the gas train will be filled with air. Even if the gas line has been completely purged of air, it may take several tries for ignition before a flame is established. If more than 5 tries for ignition are needed, it will be necessary to press the reset button to restart the boiler. Once a flame has been established for the first time, subsequent calls for burner operation should result in a flame on the first try.

9)Inspect the flame visible through the window. On high fire the flame should be stable and mostly blue (Fig.11.1). No yellow tipping should be present; however, intermittent flecks of yellow and orange in the flame are normal.

Figure 11.1: Burner Flame

10)Check the inlet pressure and adjust if necessary. Verify that the inlet pressure is between the upper and lower limits shown on the rating plate with all gas appliances on and off.

WARNING

THE OUTLET PRESSURE FOR THE GAS VALVE HAS BEEN FACTORY SETAND REQUIRES NO FIELD ADJUSTMENT. THIS SETTING IS SATISFACTORYFOR BOTH NATURAL GAS AND PROPANE. ATTEMPTING TO ADJUST THEOUTLET PRESSURE MAY RESULT IN DAMAGE TO THE GAS VALVE ANDCAUSE PROPERTY DAMAGE, PERSONAL INJURY OR LOSS OF LIFE.

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