Outdoor unit (a/c / heat pump) is having some issues. It runs great most of the time but, there are times that it pops off and on and sounds like its going to blow up or something. The off and on carp is like flipping a light switch off and on. Inside fan keeps running and outside unit makes up its own mind on what to do. Once inside temp is reached everything shuts off. What the &^%#^%#$ is going on? Thank you and stay cool.

You need a hard start kit for your compressor. If you already have one get ready for a new compressor.

Sounds like it's short cycling which is usually indicative of low freon. It is NOT the capacitor. LOL
Side note, if it's flipping on and off quickly like that, that's quite hard on the compressor and other internal components too. It's not getting a chance to equalize pressures before it cycles again.

Quite the opposite of whats been said. The whoshing sound is the reversing valve switching. If the valve is going bad or getting weak you should have the coil checked. If the seals in the valve are going back then you need a new valve. One thing that can attribute to this is higher pressure on the discharge line. Ensure the coils are clean and free of damage and leaves. Power the unit off and clean the coils carefully so as to not bend/damage them.

Could be the contactor switch. Contacts may be arched or the coil may be bad.

When it starts making the noise, use a couple of screwdrivers and push in on the square buttons and see if it stops noise and unit runs. If it runs, go buy a contactor and install it.

DO NOT DO THIS.... THIS IS A VERY BAD IDEA IF YOU DO NOT KNOW WHAT YOU ARE DOING Unless you do not value your life,limbs, eyes, etc....

It is NOT an unsafe test. You must not know what you are doing.

If he is unsure, he needs to call a repairman MOST of those that ask for repair advise on this forum should call a repairman first, then ask questions here. It is NOT an unsafe test.

Probing a contactor always makes me nervous. I've done it hundreds of times. I still get nervous.

So bill what happens when the compresser shorts to ground and blows up in his face? What happens when he slips off the plastic and touches the contact poitns and gets lit up? What happens when there is an obstruction causing over pressure and he is hit by a ruptured pipe with 700+ PSI superheated vapor and oil? WIll it be unsafe then? It is only a miracle that the OT has not gotten someone seriously hurt or killed.... But it is ok because some random guy said it was ok on the internet fishing forum.

I would say OUCH!!! That's going to leave a mark!! I've changed my contacts and capacitor in the past, just don't like to but I can do it. I've got just enough sense to cut things off and not to probe around with a screwdriver.

LOL what if the earth got hit by a huge astroid? What if a car ran into him when he tested the contactor? What if he fell on the screwdrivers and drove them thru his heart when he got them out of his tool box? You can do what if all day long, and this random guy on an internet fishing forum will still say it is a safe test.


PS: What are the breakers for? The symptoms you describe would have tripped the breaker.

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I would say OUCH!!! That's going to leave a mark!! I've changed my contacts and capacitor in the past, just don't like to but I can do it. I've got just enough sense to cut things off and not to probe around with a screwdriver. [/quote]

And that is good. If you are unsure, call a repairman.

What you described is not a capacitor or contractor symptom. It sounds like a reversing valve sticking. Pressures can be upwards of 700+ PSI with hot oil and refrigerant. Lots of dangers involved. If it is a weak contractor only... sure push it in, carefully. But when other things are at play it’s best to not just jump in without knowledge.

Thats a lot of what if's. I think I'll just here and sip on a beer, hoping I don't choke to death. LOL Y'all have a great day, we'll get this figured out.