Should AC Clutch Coil Be Hot

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arty4444
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Joined: Wed May 31, 2017 11:00 am

Should AC Clutch Coil Be Hot

Postby arty4444 » Fri Jun 16, 2017 5:44 am

I'm bench testing a new replacement AC clutch coil before installing it in a van. The coil was placed on a large iron girder and when power (14V from alternator and drawing about 3.5A) was applied the coil magnetized and after a minute or so was very hot to the touch although the 14 gauge jumper wires were not hot. This was not engine compartment heat but from the coil itself- is this normal?
Thanks
GM Tech
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Re: Should AC Clutch Coil Be Hot

Postby GM Tech » Fri Jun 16, 2017 9:24 am

Normal to get wlarm- I'd put a 10 amp fuse in-line and test it for 30 minutes- if fuse doesn't blow- you're golden.-- Although you have already quoted a good amp reading-
arty4444
Posts: 15
Joined: Wed May 31, 2017 11:00 am

Re: Should AC Clutch Coil Be Hot

Postby arty4444 » Sat Jun 17, 2017 7:16 pm

This is beyond warm. Like if you put a finger solidly on it you would have a tuff time leaving it there for as long as a second- longer and you may blister. Resistance, voltage and amps all check out but I'm replacing a coil I know has shorted and concerned about the coil wires or their slight insulation melting.
It has been suggested to me I'm testing this coil with an air core and the metal core on the compressor is needed to reduce heat.
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bohica2xo
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Re: Should AC Clutch Coil Be Hot

Postby bohica2xo » Sat Jun 17, 2017 11:41 pm

There is no inductance in steady state DC. Air core or not, it does not matter.

It gets hot? Huh. 14v X 3.5a = 49 WATTS. How long can you hold an energized 50w incandescent light bulb in your hand?

How many times did the Shorted coil blow the fuse in the vehicle?

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