Bradford-White Corp Modulating Boiler, BNTH Shutting Down Brute Elite, To Restart Brute Elite

Page 44 BRADFORD WHITE CORP.

label and turn on gas and electrical power to appliance.

4.Brute Elite will enter the start sequence. Blower and pump will energize for pre-purge, then the ignition sequence starts. After all safety devices are verified, the gas valve opens. If ignition doesn’t occur, turn off the Brute Elite, check that there is proper gas supply. Wait 5 minutes and start the unit again.

5.Turn Brute Elite on.

6.After placing the appliance in operation, the Burner Safety Shutoff Device must be tested:

(a)Close gas shutoff valve with burner operating.

(b)Flame will go out and blower will continue to run for the post purge cycle. One or three additional attempts to light will follow including pre-purge, ignitor on, valve/flame on and post purge. Ignition will not occur as the gas is off. The ignition control will lockout.

(c)Open gas shutoff valve. Reset the boiler control by pressing the RESET button on the control or on the display. Restart the appliance. The ignition sequence will start again and the burner will start. The appliance will return to its previous mode of operation.

Caution

Should any odor of gas be detected, or if the gas burner does not appear to be functioning in a normal manner, CLOSE MAIN SHUTOFF VALVE. Do not shut off switch. Contact your heating contractor, gas company, or factory representative.

10.2.2 Boiler Setup and Adjustment

1.Connect a manometer capable of reading 0.01"wc to the gas valve locations shown in Figure 33. The positive side of the manometer should be connected to the location labeled “air pressure tap.” The negative side of the manometer should be connected to the location labeled "gas pressure tap." This differential pressure should be slightly negative (see Table 16).

2.Measure the CO2/O2 in the flue products at high fire. The Brute Elite can be forced to high fire to allow for easier setup. Refer to Section 8.1, Table 14 for instructions on how to access the forced rate menu. The CO2 readings should be between the values shown in Table 16. If the CO2 is not within the range shown, adjustments may be made. To adjust the high fire CO2, locate the high fire adjuster screw according to the appropriate figure. Slowly make adjustments in 1/16 of a revolution increments until the CO2 is within the range identified.

3.Measure the CO2/O2 in the flue products at low fire. Brute Elite can be forced to low fire to allow for easier setup. Refer to Section 8.1, Table 14 for instructions on how to access the forced rate menu. CO2 readings should be between the values shown

in Table 16. If the CO2 is not within the range shown, adjustments may be made. To adjust the low fire CO2, locate the low fire adjuster screw according to the appropriate figure. Slowly make adjustments in 1/16 of a revolution increments until the CO2 is within the range identified.

4.Repeat steps 2 and 3 to confirm that the CO2 ranges are within the required ranges. Adjust if necessary.

5.Confirm that the differential pressure is still within the appropriate range.

6.If any of the measurements cannot be adjusted to the specified ranges or the CO levels are above 150ppm when adjusted please consult the factory for further information.

7.Remove the differential pressure gauge from the air and gas pressure taps making sure to close all ports after the gauge has been removed.

WARNING

Improper adjustment may lead to poor combustion quality, increasing the amount of carbon monoxide produced. Excessive carbon monoxide levels may lead to personal injury or death.

GAS TYPE	HIGH FIRE, CO2	LOW FIRE, CO2	DIFFERENTIAL
			PRESSURE
Natural	9.0 to 8.8%	0.5% lower than	-.005 to
Propane	10.0 to 9.8%	high fire setting	-.015" wc

Table 16. CO2 Range and Pressure Differential.

10.3 Shutting Down Brute Elite

1.Turn off the main electrical disconnect switch.

2.Close all manual gas valves.

3.If freezing is anticipated, drain Brute Elite and be sure to also protect building piping from freezing. All water must be removed from heat exchanger or damage from freezing may occur.

This step to be performed by a qualified service person.

10.4 To Restart Brute Elite

If drained, follow Section 10.1 in this manual for proper filling and purging.

1.Turn off the main electrical disconnect switch.

2.Close all manual gas valves.

3.WAIT FIVE (5) MINUTES.

4.Set the aquastat or thermostat to its lowest setting.

5.Open all manual gas valves.

6.Reset all safety switches (pressure switch, manual reset high limit, etc.).

7.Set the temperature controller to the desired temperature setting and switch on electrical power.

8.Burner will go through a prepurge period and ignitor warm-up period, followed by ignition.