Maintenance; System Maintenance; Appliance Maintenance And Component Description - Bradford White Brute BNTH Installation And Operation Instructions Manual

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Section 10

MAINTENANCE

Disconnect all power to the appliance before
attempting any service. Contact with electricity can
result in severe injury or death.
10.1 System Maintenance
Do this once a year, unless otherwise noted.
1. Lubricate the system water-circulating pump, if
required, per the instructions on the pump.
2. If a strainer is employed in a pressure reducing
valve or the piping, clean it every six months.
3. Inspect the venting system for obstruction or
leakage at least once a year. Periodically clean the
screens in the vent terminal and combustion air
terminal (when used).
4. Keep the area around the appliance clear and
free of combustible materials, gasoline, and other
flammable vapors and liquids.
5. If the appliance is not going to be used for
extended periods in locations where freezing
normally occurs, it should be isolated from the
system and completely drained of all water.
6. Low water cutoffs, if installed, should be checked
every year. Float-type low water cutoffs should be
flushed periodically.
7. Inspect and clean the condensate collection, float
switch and disposal system yearly.
8. When a means is provided to neutralize the
condensate, ensure that the condensate is being
neutralized properly.
9. Inspect the flue passages, and clean with a brush
or vacuum if necessary. Sooting in flue passages
indicates improper combustion. Determine the
cause for this and correct it.
10. Inspect the vent system and air intake system,
and ensure that all joints are sealed properly. If
any joints need to be resealed, completely remove
any existing sealing material, and clean the joint(s)
with alcohol. Apply new sealing material, and
reassemble.
10.2 Appliance Maintenance and
Component Description
Use only genuine Bradford White replacement parts.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and danger-
ous operation. Verify proper operation after servicing.
WARNING
Caution
The gas and electric controls in the unit are engineered
for long life and dependable operation, but the safety
of equipment depends on their proper functioning. Only
a qualified service technician should inspect the basic
items listed below every year:
a. Appliance control
b. Automatic gas valve
c. Pressure switches
d. Blower
e. Pump
Burner
Check the burner for debris. Remove the blower arm
assembly to access the burner. Remove the four bolts
connecting the blower to the arm. (See Figure 47.)
Remove the five bolts which hold the burner arm in
place. Pull the burner up and out. Clean the burner, if
necessary, by blowing compressed air from the outside
of the burner into the center, and wipe the inside clean
with glass cleaner. A dirty burner may be an indication of
improper combustion or dirty combustion air. Determine
the cause of this, and correct it. If the burner gasket is
damaged, replace it when replacing the burner.
NOTE: When installing the burner, make sure the flange
is aligned with the mating surface, as each is keyed to
control the fit.
Modulating Gas Valve / Venturi
The modulating gas valve consists of a valve body that
incorporates the On/Off gas flow control and a negative
pressure regulator. It provides the air/gas ratio control
in combination with the Venturi to the unit. It is designed
to operate with a gas supply pressure between 4 and
13 inches w.c. To remove the gas valve and/or Venturi,
shut off the 120 Volt power supply to the boiler. Turn off
all manual gas valves connecting the boiler to the main
gas supply line. Remove the front door of the boiler to
gain access to the gas valve and Venturi. Disconnect
the four flange bolts connecting the gas manifold pipe
to the gas valve. Remove the electrical connections to
the gas valve. Remove the bolts connecting the Venturi
flange to the blower. This allows the entire gas valve and
Venturi assembly to be removed to facilitate inspection
and cleaning.
Reassemble the valve/Venturi assembly in reverse
order, making sure to include all gaskets and O-rings.
Turn on the manual gas valves and check for gas leaks.
Turn on the 120 Volt power. Place the unit in operation
following the instructions in Section 9. Once the boiler
is operating. check for leaks again and confirm that all
fasteners are tight.
Check the appliance setup according to Section 9.
B W
RADFORD HITE
f. Flow switch
g. Low water cutoff
h. Burner
i. Heat exchanger