Armstrong World Industries 122, 243, 302, 242 Troubleshooting, Compressor Checkout, Initial Testing

TROUBLESHOOTING Magic-Pak: HW/HWC

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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).

WARNING

Use extreme caution when performing maintenance or troubleshooting operations. Electrical shock could cause personal injury or death.

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	SRM-
	test is complete, serious damage could be done to the compressor.
		HW/HWC

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