Armstrong World Industries 203 Air Conditioner User Manual


 
9-2
TROUBLESHOOTING Magic-Pak: HW/HWC
SRM-HW/HWC 8/99
Troubleshooting
Compressor Checkout
The objective of this section is to help in diagnosing compressor prob-
lems. It presents a series of tests that should be conducting before a
determination on the condition of the compressor is made. This section
has been organized so that the simplest checks are done first, followed by
the more detailed tests (if necessary).
Initial Testing
If a compressor failure is suspected, several simple checks should be
done initially to make sure that the right course of action is being taken.
The following is a list of items and points that should be looked at before a
determination is made of the condition of the compressor.
Is the correct voltage available at the unit? Using a volt/ohm meter,
check the voltage and compare with the voltage specified by the
manufacturer (found on the data plate on the unit). Many compres-
sors are replaced only to find later that there was either no power or
incorrect power available to the unit.
Is the contactor closing? Check to make sure that there is 24 volts at
the coil side of the contactor. Check to make sure the points in the
contactor are in good condition. Are they pitted or corroded to the
point where they no longer conduct electricity?
Is the capacitor in good condition? Does it have the correct rating for
the application? Using a meter, determine if it still has the correct
capacitance.
The last of these initial tests to do is a touch test. This should be
done very carefully as the compressor can become very hot in
certain situations. This information may be helpful if further tests are
needed to determine the condition of the compressor.
Further Testing
Use extreme caution when conducting the following tests. The power
must be turned off before continuing with the testing.
Checking Continuity
1. Remove wires from the fusite plug in the compressor, recording the
location of each wire as it is removed. If a wire is misplaced when the
test is complete, serious damage could be done to the compressor.
Use extreme caution when performing maintenance or
troubleshooting operations. Electrical shock could
cause personal injury or death.
WARNING