Bradford White U-TW4-75S-76R-3N - Manual (Page 14)

Step 5. Fully inspect burner door and right side inner door gaskets for the following:
>Tears >Other imperfections that will inhibit proper seal
>Missing Material >Gasket adhesion to inner door
>Cr acks >Material left on combustion chamber (around opening)
>Dirt or debris
If the gasket is not effected by any of the above, gasket replacement is not required. If replacement is
required, proceed to Inner Door Gasket Replacement Procedure.
Inner Door Removal Procedure
Step 1. Position gas control power switch to the “OFF”
position and unplug heater from wall outlet.
Step 2. Remove outer jacket burner access door.
Step 3. Remove wire clip from main burner feedline.
Step 4. Inner Door Removal.
a) Disconnect the spark igniter/flame sensor wire and the
simulated resistive device from the gas control (see photo 1).
b) Disconnect main burner feed line (¾” wrench), pilot tube
(7/16" wrench) and igniter wire from gas control (see photo 2).
c) Remove (2) ¼” hex drive screws from right side inner door
(see photo 3).
d) Remove (2) ¼” hex drive screws from flange section of
inner door (see photo 3).
e) Remove (3) 1/4" hex drive screws from burner door
(see photos 4&5). The burner door and burner are
one-piece.
f) Remove burner and inner door and inspect per step 5.
1
2
3
4
5
Simulated Resistive
Device
Spark Igniter/
Flame Sensor
Wire
Main Burner
Feedline
Pilot Tube
Igniter Wire
Right Side
Hex Drive
Screws
Flange Hex
Drive Screws
Burner Door
Hex Drive
Screws
Position #1
Position #2
Position #3
U TTW SERVICE PROCEDURE I
Burner and Inner Door/Gasket Removal,
Inspection, Replacement and Reinstallation
Page 14
Gas Control shown in the “OFF” position
R
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