Checking low fuel gas pressure switch
With the burner operating in low fire, close the main gas manual shutoff valve (Fig. 4).

Figure 4. Controls on LH side of burner.

This should cause the switch to open. The following reactions should occur, indicating that the pressure switch is operating properly:

1. The burner should shut down.

2. Low fuel gas pressure light on control panel should be the first light to go out.

3. Fireye flame monitor should read 3 TO P INTERLOCK OPEN.

Reset low pressure switch using manual reset button.

Checking heater fuel oil pump auxiliary contacts
With the burner operating, trip the fuel pump circuit breaker. This should cause the auxiliary contacts to open. The following reactions should occur, indicating that the contacts are operating properly:

1. The burner should shut down.

2. Low heater fuel oil pump auxiliary contacts light on control panel should be the first light to go out.

3. Fireye flame monitor should read 3 TO P INTERLOCK OPEN.

Reset fuel pump circuit breaker.

Checking Low fuel oil pressure switch
With the burner off, unlatch the auxiliary contacts module and physically remove it from the fuel pump circuit breaker with wires attached. Pull out the blue plunger on the module and hold it out so as to close its contacts. Restart the burner. Trip the fuel pump circuit breaker. The following reactions should occur, indicating that the pressure switch is operating properly:

1. The burner should shut down.

2. Low fuel oil pressure light on control panel should be the first light to go out.

3. Fireye flame monitor should read 3 TO P INTERLOCK OPEN.

Checking high media temperature
With the burner operating, note the temperature shown on the high media temperature controller (Fig. 5). Press display on the controller to view the temperature set point. Change the setpoint to a value lower than the temperature noted.

Figure 5. High media temperature controller.

The following reactions should occur, indicating that the controller is operating properly:

1. The burner should shut down.

2. The high media temperature light on control panel should be the first light to go out.

3. Fireye flame monitor should read 3 TO P INTERLOCK OPEN.

Be sure to reset the controller to its previous setpoint and to depress the reset button on the controller.