Bacharach H-25C, Инструкция, Страница: 47 / 59

H-25C Instruction Manual
Instruction 3015-0216
47
handle), allowing the air to be expelled as the liquid R - 134a enters. After a short while some misty
liquid R 134a will begin to spray out in a mist.
Wait about 10 seconds after the mist begins spraying out, and then close the tank valve. Also be sure
to close the service cylinder valve. Then, waiting about one minute between repetitions, very slightly
open the tank valve again for about 5.seconds, and repeat this action two or three times.
(10) Remove the coupler from the tank, and remount the plug as it was originally. As soon as the coupler is
removed, R - 134a gas in the tank blows off. Quickly perform the work. Tighten the plug to a torque of
about 3 N-m f 30 kgf-cm 1.
(11) Verify that enough R - 134a liquid (25 to 30 g) went into the tank. Weigh the tank, and compare the
new weight to the weight measured in " (6) ". Also examine the tank to make sure that there is no leak
from the plug area.
(12) Remount the tank in the instrument main unit. Check to make sure that the gas outlet port 0-ring is in
place, and firmly tighten two mounting screws.
(13) Adjust the calibration gas secondary pressure following the procedure given in Section 2.6.
Note that proper calibration will be impossible if any air is left in the tubing. After adjustment, loosen the
gas bleed plug for about three seconds; repeat @s action two or three time.
5.4 Replacing the Sensor
Since the sensor sensitivity will gradually deteriorate over time, you will need to adjust the " HEATER "
variable resistor whenever the sensor sensitivity displayed during calibration goes outside the permissible
range (60 to 150% on the bar graph). When the " HEATER " variable resistor shaft will not rotate any farther
in the clockwise direction, the sensor has reached the end of its useful life.
Note: Our guideline for sensor life is 900 to 1000 hours of operation. However, the life is sometimes shorter,
depending on the concentration of the reacting gases (freon, etc.) and how long they are drawn in.
When the sensor reaches the end of its life, you must replace it with a new sensor. The replacement
procedure is as follows:
(1) Turn the power switch OFF, and wait until the sensor has cooled down (about ten minutes).
(2) Remove the instrument main unit cover and the sensor chamber cover. Then remove the sensor, by
first disconnecting the tubing connector on its top and then unplugging it from its socket.
(3) Plug the new sensor into the socket. Then reconnect the tubing connector to the sensor. After thus
installing the sensor, replace the main unit cover and the sensor chamber cover.