Bradford-White Corp BWCV Internet Version for Reference Only, Bradford White, Burners, Filter

Internet Version for Reference Only

Page 32 Bradford White

The gas and electric controls on the appliance are engineered for long life and dependable operation, but the safety of the equipment depends on their proper functioning. It is strongly recommended that a qualified service technician inspect the basic items listed below every year.

a.Ignition controls

b.Ignitors

c.Water temperature control

d.Automatic gas valve

e.Pressure switches

f.Blowers

7.2.1 Burners

Close main manual gas valve before proceeding. Checking the burners for debris - Remove the ignitor inspection panels(s) and ignitor(s) and inspect the burners through the ignitor hole(s) using a flashlight to illuminate. If there is any indication of debris on the burners that are visible, all the burners will need to be inspected more thoroughly. Remove the screws from around the front of the air box (large panel from which the ignitor inspection panel(s) were removed), and remove the large panel. Remove the gas manifold assemblies and the burner panels. Inspect the burners. Clean burners, if necessary, by blowing compressed air from the outside of the burners into the center

of the burner. A dirty burner may be an indication of improper combustion or dirty combustion air. Determine the cause, and correct. Replace the burners in the reverse order

7.2.2 Filter

The filter used in the heater is washable with an

83% arrestance. Since the filter is washable, it will only need replacement when unwashable, deteriorated or damaged. If filter replacement is needed, it should only be replaced with a factory part. Inspect the air filter. If there is debris on the air filter, remove it from the filter box, and wash it with mild soap and water. Ensure that the filter is completely dry before re- installing, in reverse order.

7.2.3 Gas Valves

The gas valves are designed to operate with supply pressures of 4-13 inches w.c. (1.0 to 3.2 kPa).

To remove a valve, shut off 120-volt power and the manual gas shutoff valve. Remove the top front panel from the unit. Disconnect the wires to the valve. Disengage the flanges before and after the valve, and remove the valve. Re-install in reverse order, ensuring that the gasket o-rings are placed properly in the grooves on the flanges. Turn on manual gas shutoff valve and 120 volt power and check appliance operation and tightness of gas valve connections.

7.2.4Manual Reset High Limit Control

The high limit switch is manual reset switch

with an adjustable set point, up to 200°F (93°C). To replace the switch, shut off the 120-volt power to the appliance. Remove the cover from the switch to access the mounting screws. Remove the screws, and pull the switch off the control panel. Remove the capillary and bulb from the thermal well located in the header. Replace in reverse order.

7.2.5Automatic Reset High Limit Control

An automatic reset high limit is used in addition

to the manual reset high limit. The high limit switch has an adjustable set point, up to 200°F (93°C). To replace the switch, shut off the 120-volt power to the appliance. Remove the cover from the switch to access the mounting screws. Remove the screws, and pull the switch off the control panel. Remove the capillary and bulb from the thermal well located in the header. Replace in reverse order.

7.2.6 Temperature Control

The temperature control is a Bradford White LHSC. To replace the control, shut off the 120-volt power to the appliance. Remove the cover from the control panel, and remove the mounting screws to remove the controller. Replace in reverse order.

7.2.7 Ignition Controls

The ignition controls ensure the proved interrupted-type ignition system. They control the hot surface ignitors and prove that the flame signal is appropriate for powering the gas valves. It also controls the blower’s pre-purge and post-purge. Copper Brute II models 500 and 750 have one ignition control. Models 1000 to 2000 have two ignition controls. On models 1000, one ignition control controls stages 1 and 2, and the second ignition control controls stage 3. On models 1250-2000, one ignition control is for stages 1 and 2, and the other is for stages 3 and 4.

To replace a control, shut off the 120-volt power to the appliance. Remove the cover from the control panel. Remove the electrical connectors from the ignition control. Take out the controller’s mounting screws, and pull the controller out. Replace in reverse order.

7.2.8 Ignitors

The ignitors used are 120v “Hot Surface” type. They are energized whenever there is a call for heat and switched off when ignition is established and the flame has been sensed. Copper Brute II models 500 and 750 have one ignitor. Models 1000 to 2000 have two ignitors. To replace the ignitor, shut off the 120- volt power to the appliance, remove the ignitor access panel, disconnect the Molex connector, remove the two mounting screws on the ignitor flange, and pull the