Craftsman upright compressor trips breaker
- Thread starter ErVikingo
- Start date
truckdriver
Well-known member
One of mine was doing that and it was the start capacitor. I took it to a friend and he cleaned some of the contacts and it was fixed. On mine you could take the belt off and motor would turn very slow, with the belt it would trip breaker or overload switch.
panknuckshovel
Well-known member
I did the recall you mentioned for the cover and if I am remembering correctly the cover recall was because of this type of problem. Something about the design of the cover interferred with a switch or connection causing running problems and eventually leading to a fire. The compressor is gone, but I should have all the paperwork about it in the warranty/manual bin. I will PM what I find.
does it start OK when the tank is empty? if yes, read this thread and take special note of the cold start unloader or unloader assist in post 15 and on .
http://www.garagejournal.com/forum/showthread.php?t=196633
http://www.garagejournal.com/forum/showthread.php?t=196633
gibbon_guy
Well-known member
My compressor would trip the breaker when it was hot outside. It had some sort of underrated electrical component in the box. It also used to have issues starting from 90psi? I lowered the regulator pressure on the shop air and that seemed to help. Good advice above though
brooktre
Well-known member
When you tried different circuits were they on the same breaker? I had a similar problem and it turned out that the breaker was weak.
G_P
Well-known member
Does the motor run fine when not connected to the compressor? If it does then you have a problem with your unloader or check valve.
If it still trips the breaker when not connected to the compressor you have an internal motor issue. The contact for the centrifugal switch may be dirty or burnt or you may have a bad winding.
If it still trips the breaker when not connected to the compressor you have an internal motor issue. The contact for the centrifugal switch may be dirty or burnt or you may have a bad winding.
Will try all of these suggestions.
Pretty sure I tried to start it with the bleed valve open and it did the same thing.
How can I check the windings? (I do have the meter, just no idea how to check it)
When I tried on a different plug it was on a different breaker.
Pretty sure I tried to start it with the bleed valve open and it did the same thing.
How can I check the windings? (I do have the meter, just no idea how to check it)
When I tried on a different plug it was on a different breaker.
My compressor used to trip the breaker. It is a craftsman 33 gallon vertical oilless compressor. I did the recall for the shroud, no change. Verifyed the unloader valve was not the culprit hy bleeding the tank to 0psi. It would intermittently trip the breaker upon startup. I would hear the breaker trip, no noise from the motor really. It was on a dedicated 20 amp ckt with the outlet mounted at the panel. It did do it on the regular garage ckt also. With much research I read of a person in my same situation who had a square D panel. He got a special breaker they offer that was rated HM or high magnetic. It is like a slow blow fuse. I got it at Grainger. It has not tripped the breaker since. If you have a square D panel you are in luck. If not, maybe there is an equivalent in your brand.
Interesting. I will look at this!
well, I am finally starting to get ready to move to the new house and have gotten to the compressor. Hoping I can resurrect it rather than trash it.
I replaced one capacitor and the problem has not gone away. Apparently it is the second capacitor but the part number or specs are not visible. The kit is Start and Run capacitor D30107 and you guessed. I have not found anyone with a kit nor the specs of the large cap. All I can read is that it is a 370vac 50/60hz.
Suggestions?
I replaced one capacitor and the problem has not gone away. Apparently it is the second capacitor but the part number or specs are not visible. The kit is Start and Run capacitor D30107 and you guessed. I have not found anyone with a kit nor the specs of the large cap. All I can read is that it is a 370vac 50/60hz.
Suggestions?
jl4c
Well-known member
The start capacitor has a much higher microfarad (uF) rating than the run capacitor. I want to say the value is about 7-10x the run capacitor. I have a 55uF start capacitor sitting here in front of me that I'll send you for the cost of shipping if you want it. It's cylindrical, about 2" in diameter and 4-5" tall.
Take your suspected bad capacitor out and test it (many higher end Fluke meters will test capacitance). If it's not 7-10x the value of the run capacitor, it's bad. You can also take it to any HVAC shop and they'll have something that will work for you as the same types of capacitors are used to run your house A/C compressor. They'll get you something close enough.
Take your suspected bad capacitor out and test it (many higher end Fluke meters will test capacitance). If it's not 7-10x the value of the run capacitor, it's bad. You can also take it to any HVAC shop and they'll have something that will work for you as the same types of capacitors are used to run your house A/C compressor. They'll get you something close enough.
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Wow thanks for the offer. I will take the cap out and to an HVAC contractor before I bother you.
THANKS again for the kind offer and the suggestions. Have a great one.
