Potterton Housewarmer 45, Installation & Service Instructions Manual, Page: 42 / 45

Replacement of Parts - Page 15
c) Close the gas fire isolation tap and undo the union.
d) Loosen the 2 wing nuts securing the burner tray to the
convector box, then carefully remove the burner tray.
e) To avoid accidental spillage, carefully empty the
vermiculite (Ash Effect) out of the burner tray into a
suitable container and put somewhere safe.
On re-assembly, check the level of the vermiculite, if it is
below the level of the burner tray top surface, it will need
topping up - See instruction sheet 966/9350/3.
11.2. A.S.D Assembly
a) Perform General Access - 11.1.
b) Remove 2 screws securing the pilot sighting plate and
remove the plate.
c) Disconnect the union nut securing the pilot pipe to the
pilot injector with 2 spanners.
d) Disconnect the thermocouple from the back of the gas
tap.
e) Pull the electrode lead off the piezo unit.
f) Remove 2 screws securing the A.S.D assembly and
heat shield assembly to the burner box.
g) Fit the new A.S.D assembly and check that the spark
gap between the electrode tip and the thermocouple tip
is 3.0 to 4.0 mm. If necessary, adjustment can be made
by gripping the base of the tip with one pair of pliers
whilst gently bending the end of the tip with another pair.
Take care not to crack the ceramic insulator.
h) Re-assemble in reverse order, check for gas soundness
and correct operation of the fire.