Information Plate, II. Contactors

SEFL JOSDJ		SEFL JOSDJ
SEFL JOSDJ		SEFL JOSDJ
SEFL JOSDJ		SEFL	JOSDJ	SEFL JOSDJ		SEFL JOSDJ
SEFL	JOSDJ	SEFL		SEFL	JOSDJ	SEFL JOSDJ PAASFLDLKREW
			JOSDJ	SEFL		SEFL JOSDJCUTUHD
				SEFL JOSDJ		SEFL JOSDJHRMD
					JOSDJ	SEFL JOSDJ	ITYALK

A88411

Fig. 9—Information Plate

connection will be exposed to moisture, it is very important to cover the entire connection completely to prevent an electrochemi- cal action that will cause the connection to fail very quickly. Do not reduce the effective size of wire, such as cutting off strands so that the wire will fit a connector. Proper size connectors should be used. Check all factory and field electrical connections for tightness. This should also be done after the unit has reached operating temperatures, especially if aluminum conductors are used.

II. CONTACTORS

NOTE: The section applies to single-speed models only.

The contactor provides a means of applying power to unit using low voltage (24v) from transformer in order to power the contactor coil. (See Fig. 11.) Depending on unit model, you may encounter single-, double-, or triple-pole contactors to break power. One side of the line may be electrically energized, so exercise extreme caution when troubleshooting.

The contactor coil for residential air-conditioning units and heat pumps is powered by 24vac. If contactor does not operate:

1.With power off, check whether contacts are free to move. Check for severe burning or arcing on contact points.

2.With power off, use ohmmeter to check for continuity of coil. Disconnect leads before checking. A low-resistance reading is normal. Do not look for a specific value, as different part numbers have different resistance values.

3.Reconnect leads and apply low-voltage power to contactor coil. This may be done by leaving high-voltage power to outdoor unit off, and turning thermostat to heat or cool. Check voltage at coil with voltmeter. Reading should be between 20v and 30v. Contactor should pull in if voltage is correct and coil is good. If contactor does not pull in, change contactor.

4.With high-voltage power off and contacts pulled in, check for continuity across contacts with ohmmeter. A very low or zero resistance should be read. Higher readings could indicate burned or pitted contacts which may cause future failures.

SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ

	SEFL	JOSDJ
	SEFL
		JOSDJ
	SEFL
		JOSDJ

SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ

SEFL
SEFL JOSDJ
SEFL JOSDJ PAASFLDLKREWATC
SEFL JOSDJ UTUHD
SEFL JOSDJC MD
JOSDJHR	ITYALK
SEFL JOSDJ

SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ

	SEFL	JOSDJ
	SEFL
		JOSDJ
	SEFL
		JOSDJ

SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ SEFL JOSDJ

SEFL JOSDJ
SEFL JOSDJ
SEFL JOSDJ PAASFLDLKREWATC
SEFL	UTUHD
SEFL JOSDJC MD
JOSDJHR		ITYALK
SEFL JOSDJ

A88412

A88413

Fig. 10—Information Plate Removed/Installed Below Control Box

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