A-dec 500 User Manual 135-144

85.0816.00 Rev A 2004-11 (PCA 04002.12) Page 135

A-dec Service Guide, Vol. II Floor Box

The A-dec 500 floor box is needed if a delivery system, assistant’s instrumentation, or a
cuspidor is installed. The floor box is mounted over the utilities on the floor of the
treatment room and contains the air and water manual shutoff valves, filters, air and
water regulators, pressure pre-regulator, vacuum, and gravity drains as well as
electrical outlets.

This section provides information related to servicing, maintenance, and adjustments.
Detail on how to service the floor box and troubleshoot specific problems is presented.
For information on service parts, see the Genuine A-dec Service Parts Catalog or contact
A-dec customer service.

Page 136 85.0816.00 Rev A 2004-11 (PCA 04002.12)

Floor Box A-dec Service Guide, Vol. II

How the Floor Box Functions

Air and Water Manual Shutoff Valves

Shutoff valves supply the air and water to the unit. To prevent leaks, these
valves should remain fully open (turned counterclockwise) except while the
unit is being serviced.

Gauge and Pre-Regulator

The pre-regulator controls the air and water pressure in the unit. The gauge
displays the unit air pressure.

A

B

F

C

D

E

G

Figure 96. Identification of the floor box utilities. (A) electrical
duplex outlet; (B) water filter regulator; (C) Air filter regulator;
(D) gauge and pre-regulator assembly; (E) moisture separator;
(F) vacuum drain; (G) cuspidor drain

85.0816.00 Rev A 2004-11 (PCA 04002.12) Page 137

A-dec Service Guide, Vol. II Floor Box

Filter Element

A clogged filter will reduce the amount of air and water pressure available to the unit.

1. Move the master On/Off toggle to OFF.

2. Close the manual shutoff valves.

3. Bleed the system of air and water pressure by operating the syringe buttons until air and water no longer flow.

4. Remove the filter housing from the air and/or water regulator assembly with a flat blade screwdriver.

5. Replace the filter if it is visibly clogged or discolored.

6. Install the new filter with the beveled edge toward the manifold.

NOTE: The system will not work properly if the filter is installed incorrectly.

Figure 97. Replace the filter by removing the filter housing
and installing the new filter beveled edge down. (A) filter
housing; (B) new filter

A

B