Contactor on Central Air Blew up
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Contactor on Central Air Blew up
This is the 4th time in a year that my AC went out. The first time the contacts were pitted and black. I filed them down and reinstalled it. That was over the 4th of July last year. It worked the rest of the summer that way. This year over Memorial Day weekend it went out again. This time the contacts were gone. I replaced the contacts on the existing contactor and it worked till last week. When I took off the panel, I noticed that the contact had blown off the contactor. I replaced it with a new contactor and a week later, it blew the contacts clear off that one too. I checked the voltage and all looks normal. Any ideas? Thanks.
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It's a 2.5 ton unit and a 30 amp contactor. Should be the right size. I havn't been able to measure the draw yet because the contactor is not functional. I talked to a hvac technician and he recommended trying a 40 amp contactor and keeping an eye on it. Does that sound like good advice? In a month, our power company will fix if for free through a maintenance program that they offer. So I just need to keep it going till then.
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The 30 amp sounds right .Dont think id go for a 40 amp till I found out I need it. So that means to amp the unit. Also you might Ohm out the compressor. Could need a good start kit. One that has a potential relay with it.
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Not sure if this will help or not, but do you have any ants around your outside unit? If so, ants love voltage for some reason and they will get into the electrical components of the unit. My contactor shorted out because of them.
Sprinkled some serious ant killer powder all around the unit and have not had problems since.
Sprinkled some serious ant killer powder all around the unit and have not had problems since.
#6
never seen one explode very unusual I would go back and double check the contactor that you installed, you could very well have the wrong one, what comes to mind is a 24 volt control contactor installed in a unit that uses 120 volt control to its contactor BLAM but anyway we all do know that all these parts are now manufactured overseas by starving child slave labor in places like bangledesh so the quality could be kinda low maybe switch to another brand contactor and make SURE you match the units control voltage and get proper amperage contactor.