Q. Why is my dehydrator running constantly?
A. Excessive leakage or a faulty compressor can cause a dehydrator
to run constantly. A dehydrator will operate continually when it
is not capable of supplying the airflow demanded by the pressurization
system. Leakage in the transmission line or connections can be large
enough to cause excessive operation. Check the polytubing and all
transmission line connections for leakage. Use a commercial leak
detector or soapy water on joints. Bubbles indicate leaks. A dehydrator
compressor that is worn beyond its useful life also can force the
unit to run constantly.
Q. What do I do if there is a build-up of water in the filter bowls?
A. The problem is most likely with the compressor where the pressure
output has dropped. Alternatively, there may be a blockage in the
brass fitting positioned below the bowl. Remove the filter bowl and
clean the orifice at the base, check for small air flow if none test
the compressor. The compressor may need to be rebuilt.
Q. What type of fittings are required to install my dehydrator?
A. All fittings are included in the installation kit that comes
with the Andrew dehydrator you have selected.
Q. The dehydrator has been properly fitted, yet there is a small
amount of leakage. Is this normal?
A. Yes. There will always be a small leak of between 1 and 5 percent
in your system. On the MT/XT Series of dehydrators, leakage increases
to 4-8 percent because of feedback through the membrane.
Q. What spare parts should I keep on hand?
A. The operator's manual for every Andrew dehydrator includes a
list of replacement parts for the unit.
Q. Does my compressor require lubrication?
A. No. All Andrew-manufactured dehydrators use oil free compressors
with sealed bearings.
Q. On my X Series dehydrator, the alarm contacts do not read "open" or "closed".
Why is this?
A. Andrew X Series monitors use solid state relays which do not
indicate an "open" or "closed" circuit (as a
form "C" dry contact relay would). The X Series unit power
does not come on and the power switch does not light up. Check the
unit's power cord to make sure that it is pressed completely into
the IEC socket on the unit.
Q. When using an X Series line monitor, a low pressure alarm is
signaled for ports not in use. How can I correct this?
A. Check the unit to make sure that the dip switch is set for the
correct number of ports being used. (Refer to the owner's manual
for the specific unit.). Or, cap the unused ports and open the valves
at the bottom of the flow meters.
Q. The dehydrator cycles on, then off very rapidly. Does this indicate
a problem?
A. This may not be a problem with the dehydrator at all. Rapid on-off
cycling usually indicates that the dehydrator is able to pressurize
the system volume very quickly. Check to see that the valves are
open to the waveguide. Rapid cycling may indicate that the dehydrator
is too large for the system.
Q. Is a bigger dehydrator better?
A. Not necessarily. A properly sized dehydrator for your system
will work best. First, determine the total waveguide volume. Then,
using the Andrew catalog or PSI Select software, select a dehydrator
that is matched to that volume having the other features desired.
Q. How often should I change the filters in the water bowls?
A. Filters should be changed every 6,000 hours, or when the compressor
is rebuilt. Replacement filters are included in the unit overhaul
kit.
Q. Can I use my dehydrator to purge the waveguide?
A. Yes. All Andrew dehydrators can be run to purge the waveguide.
This extended run will not damage the dehydrator.
Q. Why does the MT050 compressor run so often?
A. The MT050 has an internal air tank that is used to provide a
dry air source for the bleed air used to keep the membrane tube dry.
The run cycle is not dependent on system volume or condition.
Q. When do I need to rebuild the compressor in my dehydrator?
A. The compressor should be rebuilt at least every 6,000 hours.
Pressurization
