Testing Procedure - Panasonic SR-GA421 Service Manual

4. TESTING PROCEDURE

1. Bubbling test
Input the pan in the main body, and lightly rotate the pan clockwise and counter clockwise
to set the pan on the heating plate properly.
1. Fill water until the center area of the pan bottom is dipped, and close the lid. Then turn
on the boiling switch.
2. When it beings boiling to produce steam, remove the lid and immediately check the
bubbling condition on the pan bottom.
3. Bubbling condition is shown in figure 3.
A. Bubbles generate through out the circumference of the pan bottom ............... Proper
B. Bubbles does not generate on more than one quater part of the pan bottom
circuference .................................................................................................. Improper
Water Level
Sheathed heater
If it is improper, it may result from the insfficient contact between the pan bottom and
the sheathed heater. Check the pan bottom and the sheathed heater for foreign material
remained. Clean up the foreign materials or replace the parts.
2. Evaporation test
1. After satisfactory bubbling is confirmed, remove the lid and put a weight on the cooker.
2. Cover the entire pan bottom with 2 or 3 pieces of tissue paper (or gauze), and turn on
the switch subsequently.
3. The cooker is considered acceptable if the timing when steam generation comes to
a stop after water of the pan bottom has evaporated, is within 1 minute before and
after the cooking switch is turned off. If these requirements are not satisfied, check the
center thermostat as well as the contacted condition between the pan bottom and the
cooking heater, and then repair or replace the parts.
Center thermostat
Figure 2
5 cm.
COOK
WARM
Water Level
A
Figure 3
Pan (viewed from above)
Holes of
tissue paper
9
SR-GA421/SR-GA281/SR-GA721
B
Pan flange
section
Tissue paper