Robinair 14830A Thermistor Vacuum Gauge - Manual (Page 2)

Model 14830A
Thermistor Vacuum Gauge
Description
The 14830A Thermistor Vacuum
Gauge has been designed to use with
high vacuum pumps to accurately
measure vacuum level during evacuation
of A/C and refrigeration systems. This
unit indicates precisely when the system is
free of air and water, eliminating guess-
work and saving valuable service time. It
can also be used to check for leaks without
precharging; if the system holds a vacuum, it
is leak-free.
Battery and A/C powered and self-contained in a durable carrying
case, the 14830A is easy to use and transport. The sensor is built into
the unit and connected to the system through a fitting on the front panel.
A 24” Premium Refrigerant Charging Hose is included for connecting
the thermistor and the system. The hose is stored in a recessed area of
the case.
Power Supply
The 14830A can be used with an A/C power adapter or 4 “D” cell
batteries. See below for A/C adapter requirements.
*A/C adapter output: 6VDC 200mA, + outer ring and
- center pin. Robinair Part No. 18712, 110V.
LCD Range and Tolerance
The 14830A uses the micron scale, the most accurate indicator of
vacuum, measuring from atmosphere to 50 microns. Micron readings
are shown on a custom LCD divided into 10 segments which are shown
as “bars” on the LCD. These segments are:
25,000 microns ................. ±5,000 microns
2,500 microns ...................... ±500 microns
1,300 microns ...................... ±100 microns
1,000 microns ...................... ±100 microns
700 microns ......................... ±100 microns
400 microns ........................... ±50 microns
275 microns ........................... ±25 microns
200 microns ........................... ±25 microns
100 microns ........................... ±10 microns
50 microns ............................... ±5 microns
Operating Instructions
1. Install four “D” batteries into the holder by removing the screw on
the bottom of the battery plate holder. Lift out the plate and install the
batteries into the holder following polarity indicators. Replace the
battery plate into the unit panel by sliding in the top edge first and
secure with the screw.
2. Connect the 24” hose to the flare fitting marked “Vacuum” on the front
panel.
3. Connect the other end of the hose to the system.
CAUTION: Before attaching the hose to the system, depressurize the
system. Damage to the sensor may occur if the connection is made
while the system is pressurized.
4. Turn the power ON and allow one minute for the unit to warm up.
5. Check the LCD window. If all 10 “bars” appear on the screen the
system is above 25,000 microns (1” Hg vacuum).
6. Begin evacuating according to the system manufacturer’s specifica-
tions. As the system is pumped down, the “bars” on the LCD will go out
one by one. At the point when the bar goes out, the system is at the
vacuum level shown next to that bar.
CAUTION: When you finish the evacuation cycle and during equip-
ment shut-down, close any valve between the gauge and the pump
or open the connection at the flare fitting on the instrument panel.
Maintenance
1. The word BAT will appear on the display when the batteries need
replaced. Replace the batteries as soon as possible.
2. If the sensor aquires an oil film, flush the interior with rubbing alcohol
and allow to air dry.
3. If the unit is not going to be used for an extended period of time,
remove the batteries to eliminate possible battery damage due to
leakage.
4. The panel may be cleaned with a damp cloth. DO NOT use harsh
solvents and/or chemicals to clean.