Bradford-White 50T65F(BN User Manual

Size:
1.47 Mb
Download

SERVICE PROCEDURE RG-IV

Piezo Igniter, Electrode

Testing and Replacement

Piezo Igniter, Electrode Testing and Replacement

With the pilot not in operation (no pilot flame) you can check the Piezo and electrode circuit by viewing pilot thru the sight glass located on the inner door and observing the spark action.

Step 1. Remove outer jacket door.

Step 2. Repeatedly depress the Piezo igniter while viewing the pilot thru the sight glass. If a spark is present, the circuit is OK. If there is no spark, proceed to step 3.

Repeatedly

Depress Piezo

Igniter View spark Action through

Sight glass

Remove orange wire from Piezo igniter and install a jumper wire in its place. Hold per by the wire insulation or using an insulated tool, next to an unpainted

or gas valve and depress the Piezo igniter. If there is a spark, the igniter is OK, functioning and must be replaced, see SERVICE PROCEDURE RG-IIIfor pilot re present the igniter is not functioning and must be replaced.

orange wire disconnected from Piezo igniter. Using a common screw driver, under Piezo bracket and gently pry bracket from front of combination

unhook bracket from rear of combination thermostat/gas valve.

Common

Screw Driver

11

SERVICE PROCEDURE RG-V

Combination Thermostat/Gas Valve

Testing and Replacement

Combination Thermostat/Gas Valve Testing and Replacement

The combination thermostat/gas valve is a non repairable device. If trouble shooting has determined a problem with the combination thermostat/gas valve, it must be replaced. If the burner and/or pilot do not function, service checks for gas pressure, thermocouple output, magnet assembly and ECO are to be performed. If these check OK, the combination thermostat/gas valve may be faulty.

LINE PRESSURE

The combination thermostat/gas valve is designed for a maximum line pressure of 14.0" w.c. and a minimum line pressure of 1.0"w.c. over the water heater rated manifold pressure.

MANIFOLD PRESSURE TESTING (this procedure assumes a maximum line pressure of 14.0" w.c.)

Step 1. Set combination thermostat/gas valve to “OFF” position.

Step 2. Remove pressure tap plug (3/16" Allen wrench) and install pressure tap (7/16 wrench)

Pressure Tap

Shown Installed

Step 3. Connect manometer to pressure tap.

Step 4. Follow lighting instructions and proceed to light main burner.

Step 5. Manometer gauge should read 4.0" w.c. for Natural gas and 10.0" w.c. for L.P. gas

Step 6. If adjustment is necessary proceed to step 7. If pressure is OK, set combination to “OFF” remove manometer and pressure tap and replace pressure tap plug. before placing water heater back in operation.

Step 7. While burner is in operation, remove regulator access cap to expose the regulator

With small screw driver, rotate adjusting screw clockwise to increase pressure and to decrease pressure.

Step 8. Set combination thermostat/gas valve to “OFF”. Remove manometer and pressure tap plug. Check for gas leaks before placing water heater back in o

12

SERVICE PROCEDURE RG-V

Combination Thermostat/Gas Valve

Testing and Replacement

THERMOCOUPLE TESTING

See SERVICE PROCEDURE II

MAGNET ASSEMBLY TESTING

Step 1. Disconnect thermocouple from combination thermostat/gas valve.

Step 2. Connect a thermocouple adapter (BWC P/N 239-44642-00,Robertshaw P/N 75036) at the thermocouple location in the combination thermostat/gas valve.

Step 3. Reconnect thermocouple to adapter. Make certain all connections are tight (finger tight plus 1/4 turn).

Step 4. Using a multimeter capable of measuring millivolts, connect one alligator clip to the set screw of the adapter and the other alligator clip to copper portion of the thermocouple.

Step 5. Following the lighting instruction label on the heater, proceed to light the pilot and allow to operate for three minutes.

Step 6. With a meter reading of 13 millivolts or greater, rotate knob of combination thermostat/gas valve to the “OFF” position.

Step 7. The magnet should remain closed for a drop of at least 5 millivolts. You will here a “snap” or “click” sound when the magnet opens, if you hear this sound prior to a drop of 5 millivolts, the magnet is out of specification and the combination thermostat/gas valve should be replaced.

ECO (Energy Cut Off) TESTING

Step 1. Disconnect thermocouple from combination thermostat/gas valve.

Step 2. Using a multimeter capable of measuring Ohms (or continuity), attach one lead (alligator clip) to the pilot tube. Insert the other lead (probe) fully into the magnet opening, Be sure the probe makes contact only at the top center of the magnet opening. Do not allow the probe to make contact with the threaded sides of the opening.

Step 3. If continuity is indicated, the ECO is OK. If continuity is not indicated, the ECO has opened and the combination thermostat/gas valve must be replaced.

13

SERVICE PROCEDURE RG-V

Combination Thermostat/Gas Valve

Testing and Replacement

COMBINATION THERMOSTAT/GAS VALVE REPLACEMENT

Step 1. Rotate knob of the combination thermostat/gas valve to the “OFF” position.

Step 2. Turn off gas supply to water heater.

Step 3. Disconnect gas supply line from combination thermostat/gas valve.

Step 4. Turn off water supply and drain water heater completely.

Step 5. Remove outer jacket burner access door.

Step 6. Right side inner door removal.

a)Disconnect resettable thermal switch wire leads (leading from combination Thermostat/Gas Valve) and remove wire tie from feedline.

b)Remove (2) 1/4" hex drive screws from right side inner door.

c)Remove (2) 1/4" drive screws from flange section of inner door.

d)Remove right side inner door and set aside. Be careful not to damage gasket material on inner door.

Switch

Remove Wire Tie

1/4" Hex Drive Screws shown on Right Side Inner Door

1/4" Hex Drive Screws at Flange section of Inner Door

14

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SERVICE PROCEDURE RG-V

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Combination Thermostat/Gas Valve

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Testing and Replacement

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Step 7.

 

 

 

 

 

 

Removal of combination thermostat/gas valve.

Refer to

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SERVICE PROCEDURE RG-IV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a) Disconnect main burner feedline

 

 

 

 

 

 

 

to remove Piezo igniter

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(3/4” wrench), pilot tube (7/16"

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

wrench) and thermocouple (3/8"

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

wrench) from combination

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

thermostat/gas valve & remove

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

from the combustion chamber.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

b) Remove Piezo bracket with Piezo

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

igniter (refer to SERVICE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PROCEDURE RG-IV)from

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

combination thermostat/gas valve.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

c) Remove combination thermostat/gas valve from heater, rotating counter clockwise using an

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

appropriately sized wrench. Use caution not to damage cast aluminum body of combination

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

thermostat/gas valve.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Step 8.

 

 

 

 

 

 

Installation of combination thermostat/gas valve.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a) Install new combination thermostat/gas valve. Be certain not to damage the bundled wire leads.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Note: combination thermostat/gas valve must be installed in proper upright position to

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

assure the feedline will align properly at the inner door flange.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

b) Reattach Piezo bracket with Piezo igniter to combination thermostat/gas valve.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

c) Reattach main burner feedline, pilot tube and thermocouple to combination thermostat/gas valve.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

d) Gather wire leads of combination thermostat/gas valve and Piezo igniter and secure along side of

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

feedline using new wire tie provided.

 

 

 

 

 

 

 

Step 9.

 

 

 

 

 

 

Reinstallation of inner door assembly.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a) Prior to reinstallation of inner door, fully inspect inner door gasket for the following:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

> Tears

 

> Gasket Adhesion to inner door

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

> Missing material

 

> Other imperfections that will inhibit proper seal

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

> Cracks

 

> Material left on combustion chamber

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

> Dirt or debris

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

If the gasket is not affected by any of the above, gasket replacement will not be required.

If replacement is required, replace using new gasket kit following the instructions provided with kit.

15

SERVICE PROCEDURE RG-V

Combination Thermostat/Gas Valve

Testing and Replacement

Step 9. Reinstallation of inner door assembly. (cont.)

b)Clean any gasket residue or other debris from combustion chamber surface before installing the inner door/gasket assembly.

c)Position thermocouple, pilot tube and Piezo wire against left side inner door flange gasket.

DO NOT ROUTE THROUGH RADIUSED CHANNEL WITH FEEDLINE. Be sure that thermocouple and pilot tube are not in position to interfere with outer jacket burner access door when reinstalled.

 

 

 

! WARNING

 

 

 

A seal breach may result in a fire or

Position thermocouple,

 

 

explosion causing property damage,

 

 

personal injury or death.

pilot tube and Piezo wire

 

 

 

 

 

 

 

 

 

 

side inner door flange against the left side inner door flange and secure with two screws from step 6c. DO NOT OVER TIGHTEN SCREWS.

inner door to combustion chamber and verify the fastener holes of the combustion aligned with the right side inner door slotted openings. Verify seal integrity around pening. Secure right side inner door using 1/4” hex drive screws from step 6b.

TIGHTEN SCREWS. Verify both left and right sides of the inner door are properly sealed against the combustion chamber.

Secure flange with

 

Verify threaded hole

1/4" drive screws

 

 

 

alignment with slotted

 

 

openings in inner door

 

 

 

Step 10. Reconnect wire leads from combination thermostat/gas valve to resettable thermal switch (See photo in step 6). Note: wire terminations are interchangeable with either resettable thermal switch connection.

Step 11. Replace outer jacket burner access door.

Step 12. Reconnect gas supply to combination thermostat/gas valve.

Step 13. Resume water supply to water heater. Be sure tank is full of water.

Step 14. To resume operation follow the instructions located on the lighting instruction label or the lighting

instructions located in the installation and operation manual.

16

SERVICE PROCEDURE RG-VI

Burner Operation Inspection,

Adjustment, Cleaning and Replacement

MAIN BURNER: Inspection, Adjustment, Cleaning and Replacement

At periodic intervals (not more then 6 months) a visual inspection should be made of the main burner for proper operation and to insure no debris accumulating.

Main burner should light smoothly from pilot and burn with a blue flame with a minimum of yellow tips.

Steel burner models have a self adjusting air mixture and do not have an adjustable air shutter. Cast iron burner can have the gas and air mixture properly proportioned by adjusting the air shutter on the mixer face of the main burner (see step 2 below).

Main burner must be free from any debris accumulation that may effect burner operation (See next page for cleaning procedure).

CAST IRON BURNER ADJUSTMENT

! DANGER

Under no circumstances shall flammable materials be used or stored in the vicinity of the water heater. With the inner door removed the Bradford White Defender Safety System will be inactivated.

If flammable vapors are present, a fire or explosion may result causing property damage, personal injury or death.

Upon completion of the cast iron burner adjustment procedure, the inner door must be replaced per SERVICE PROCEDURE RG-1,steps 4 through 14 to reactivate Bradford White Defender Safety System.

! WARNING

Inner door and burner components may be HOT when performing this operation. Take necessary precaution to prevent personal injury.

Step 1. With main burner in operation, remove right side inner door per service procedure I, steps 3b & 3c. Be sure to maintain wire connection to resettable thermal switch for this adjustment procedure.

Step 2. To adjust for proper burning, loosen the air shutter nut, rotate the shutter to close the opening in the burner, then slowly rotate the shutter until the yellow tips disappear and the flame becomes blue. Tighten the air shutter nut. Too much air will cause the flame to lift off the burner ports and create noisy burner operation. Too little air (yellow tips) will result in soot formation. Place right side inner door into proper position to confirm proper burner flame pattern and correct air shutter adjustment. It may be necessary to allow the burner to operate for several minutes for burner flame to stabilize.

Air Shutter Nut

17

SERVICE PROCEDURE RG-VI

Burner Operation Inspection,

Adjustment, Cleaning and Replacement

MAIN BURNER: Inspection, Adjustment, Cleaning and Replacement (cont.)

Step 3. Fully inspect inner gasket per SERVICE PROCEDURE RG-I,step 4. Replace gasket if required following SERVICE PROCEDURE I, steps 5 & 6.

Step 4. Be certain that thermocouple, pilot tube and Piezo wire are routed by inner door flange as shown and Reinstall inner door per SERVICE PROCEDURE RG-I,step 10 and 11.

Position thermocouple, pilot tube and Piezo wire

Step 5. Observe burner operation

2, if not, repeat procedure com door in place.

should operate as adjusted in step proper burner operation with inner

Step 6.

It may be necessary to clean main

 

achieve proper burner operation.

 

If cleaning is required proceed to

procedure.

BURNER CLEANING (Steel & Cast Iron)

 

 

 

Step 1.

Remove inner door assembly per

ps 1 through 3c.

Step 2.

Disconnect main burner feed line

wrench) and thermocouple (3/8)

 

wrench from combination

 

assembly from combustion

 

chamber.

 

 

 

Step 3.

Thoroughly inspect burner surface

 

any loose debris accumulation.

 

 

 

 

Burner

 

 

 

 

 

 

 

 

 

 

 

 

Surface

 

 

 

 

 

 

Area

 

 

 

 

 

 

 

 

 

Burner

Port

Area

Step 4.

On cast iron burners, inspect for

 

Burner Venturi

 

any debris build up inside burner

 

 

 

 

venturi. If found, disconnect

 

Opening

 

feedline from burner and remove

 

 

 

debris build up.

 

Feedline

 

 

 

 

18

SERVICE PROCEDURE RG-VI

Burner Operation Inspection,

Adjustment, Cleaning and Replacement

BURNER CLEANING (cont.)

Step 5. Disconnect (unscrew) main burner (stamped steel “B” burner) from main burner orifice or on cast iron burners (“C” burner), loosen air shutter & disconnect (unscrew) feedline from burner.

Step 6. Remove main burner orifice from feed line (1/2” wrench on steel burner, 3/8" wrench on cast iron). Inspect and clean if necessary.

Step 7. Remove pilot assembly, refer to SERVICE PROCEDURE RG-IIIfor cleaning and inspection.

Step 8. Reassemble burner.

Step 9. Inspect combustion chamber area of heater prior to reinstallation of burner assembly. If cleaning is required, refer to SERVICE PROCEDURE RG-VIII.

Step 10. Reinstall burner assembly into combustion chamber, reconnect feedline, thermocouple and pilot tube to the combination thermostat/gas valve.

Step 11. Reinstall inner door per SERVICE PROCEDURE RG-I,steps 4 through 13.

Step 12. To resume operation, follow the instructions located on the lighting instruction label or the lighting instructions located in the installation and operation manual.

19

SERVICE PROCEDURE RG-VII

Resettable Thermal Switch

Testing and Replacement

RESETTABLE THERMAL SWITCH CONTINUITY TESTING

Step 1. Remove outer jacket door.

Step 2. Disconnect wire leads from resettable thermal switch.

Step 3. Using a multimeter capable of measuring continuity (Ohms), place one probe of meter on one of the brass connection tabs of the resettable thermal switch, and the remaining probe on the other connection tab.

Step 4. If continuity is indicated, the switch is closed, allowing millivolt current to pass.

Step 5. If continuity is not indicated, the switch is open, possibly due to an overheating condition. The switch is designed to open at predetermined temperatures depending on model. An open switch can be reset by depressing the red colored button located at the center of the switch.

The overheating condition must be determined prior to putting the heater back in service.

PROBABLE CAUSE FOR RESETTABLE THERMAL SWITCH ACTIVATION

PROBABLE CAUSE

CORRECTIVE ACTION

 

 

 

 

1. Verify adequate combustion air supply is available.

Insufficient

2. Clear jacket slot openings of any dirt, dust, restrictions

combustion Air

or other obstructions.

 

 

3. Inspect flame arrestor plate and clean with stiff brush

 

and/or vacuum to remove scale deposits and debris.

 

 

 

1. Weak switch or

1. Replace resettable thermal switch

switch out of

 

 

calibration.

 

 

2. Incorrect switch.

2. Verify switch color code and approximate temperature.

 

 

 

 

 

Flammable vapor

1. Replace water heater.

incident

 

 

 

 

 

Resettable thermal switch color code reference.

Approximate switch

Color Code activation temperature

(open)

Blue 240˚

Yellow 270˚

Red 290˚

20