Remove the rust and corrosion within the water compartment, as necessary, with solvent, and paint the bare spots with heat-resistant aluminum paint.

Check the thermostat with a mercury thermometer. The thermostat must be accurate to within either plus or minus 5F.

NOTE

Use table P of appendix II to check other items that apply to this equipment.

DISHWASHERS

From time to time, you may be called upon to adjust dishwashing machines that have become defective (figs. 5-4 and 5-5). Some of the most common difficulties, the usual reasons for their occurrence, and possible remedies for them are listed in table Q of appendix II.

Now and then, descaling deposits from within the machine, the piping, and the pumps will be required. You can fill the tank halfway with hot water, add an approved cleaning solution, fill the tanks to overflowing, and then operate the machine for 30 minutes at high temperature with trays, spray arms, and curtains in place. Next, drain the tanks and fill them with hot water and run the machine for 5 minutes. This rinsing action should be repeated several times to make sure all of the cleaning solution is removed from the unit.

Dishwashing machines and accessories should be lubricated according to the manufacturer's instructions. This is especially true in the selection of

Figure 5-4. - A semiautomatic single-tank dishwasher.