AADCO 737 Series, Operating Instructions Manual, Page: 27 / 72

23
12.0 PREVENTIVE MAINTENANCE.
12.1
BALLAST BLEED - All accumulated water must be bled from the ballast tank
at least once every three days during continuous operation. This is done by
operating the manual toggle valve, Figures 1, 2 and 9 (12), located on the
ballast tank. There should be a firm flow of air from the BALLAST BLEED
tubing, usually accompanied by water which can be caught in a suitable
container and discarded. The tank should be drained completely. During
periods of high humidity the ballast tank should be bled every day.
12.2
BLEED SYSTEM - A weekly routine check should be made for plugging of the
bleed system. When the bleed valve is opened there should be a strong flow of
air from the BALLAST BLEED tubing. If the air flow is weak or no water is
emitted, there is a possibility that there is some blockage within the tubing
leading to the bottom of the tank or the manual valve.
12.3
FILTERS - All filters should be cleaned and replaced once per month if the
compressor operates continuously. The filters in question are the two inlet
filters on the compressor, Figure 8 (44).
12.4
METHANE REACTOR - A one or two minute observation of the METHANE
HEAT lamp, Figure 4 (4), should reveal cycling of the lamp. This gives positive
indication of heat control to the methane reactor. A glance at the pyrometer will
also reveal that the unit is at temperature (290

C ± 10

C). If either check
reveals some problem, see Section 13.22 for remedial action.
12.5
COMPRESSOR (See Section 7.0) - A check of the INPUT PRESSURE
gauge, Figure 4 (3), over a one or two minute period should reveal: (a) the
compressor is operating properly (reaches a maximum pressure of about 80-
psig and cuts off), and (b) the pressure switch/compressor pressure relief
system is operating properly (cycles between 60-psig and 80-psig over a one
minute period). If not, see Section 14.0 for remedial action.
12.6
PURIFICATION REACTOR - A one or two minute observation of the rotameter,
Figure 4 (10), should show the rotameter ball as remaining constant. If both the
rotameter ball and the OUTPUT PRESSURE gauge, Figure 4 (6), show sudden
drops during a one minute cycle, see Section 13.8 for cause and remedy.