Service manual

AMERICAN DISH SERVICE

TECHNICAL SUPPORT MATERIAL

Preventative Maintenance

QUESTIONS TO EVALUATE OPERATION OF CONVEYOR MACHINES

1. Will the machine ﬁ ll with water when it is turned on for the ﬁ rst time during a new work period? If it does

not ﬁ ll, is the “ON” light illuminated when the master switch is turned on? If not, the machine will need

electrical service. [SERVICE ITEM]

2. When the machine ﬁ lls with water, what is the incoming water temperature? It should be 120°F for

Chemical Sanitizing and 160°F for Hot Water Sanitizing. This requirement is supplied by the building’s

primary water heating source. [BUILDING MAINTENANCE]

3. After the machine has ﬁ lled with water, a rack of dishes can be pushed into the machine on the “soil

table” side. The wash pump and the conveyor should begin operation. If they do not, look at the

inspection door, is it fully closed? Look at the table limit switch (if one is being used); is a rack or other

item pushing on the switch activator? These switches must be closed (meaning not activated) for the

operation to begin. [OPERATOR ERROR]

4. Does the machine continually ﬁ ll, causing the primary water-heating source to run out of hot water? This

condition will be a result of water escaping from one or both of the tanks:

The rinse tank is likely to pump out water via a bent deﬂ ector ﬁ n on the pumped rinse spray arm.

This can be remedied by bending the ﬁ n back in line, so that the sprays are falling straight down

and pumping straight up (12:00 o’clock & 6:00 o’clock). This problem most often occurs as a result

of striking the spray arm against a table or trash can to clear soil stuck in the arm. [OPERATOR

ERROR]

For the wash tank, the likely cause will be water cascading out on the soil-table. This is remedied

by correct installation of the tables. The scrap sink must be no closer to the entrance of the

machine than 20 inches; and the tables must pitch into the machine so that water ﬂ ow on the table

surface will return to the machine. Quick drains or table scuppers are not used on “stage washers.”

[INSTALLATION ERRORS]

NOTE: The auto-ﬁ ll feature should not operate during normal use, its only operation is at the ﬁ rst of the shift

when the machine is off and empty. Intermediate ﬁ lling is an indication of installation problems.

5. Is the ﬁ nal rinse water at the correct temperature? 120°F min. for Chemical, and 180°F min. for

High Temp. The correct ﬁ nal rinse temperature is critical to operational temperature. [BUILDING

MAINTENANCE]

6. When the last rack exits the machine, will the conveyor and ﬁ nal rinse shut down? If not, open the

inspection door and check the rack guide sequence switches (magnet bars, which hang down from

the rack guide). Look for a glass or bowl that may be obstructing the bar and keeping it from hanging

straight down (at 6:00 o’clock). [OPERATOR ERROR]