unit needs resetting over and over??

[garytulsa]

Can anyone help with this one? I have this 12 ton carrier package unit that has a call for cooling but compressors arent running or outdoor fans. I got voltage but contactors are not engaging. I was told to just hit the disconnect and give it five minutes and turn it back on and it will run. I took a look at it and and found the contactors wont pull in, with a little nudge they suck right in. any ideals what i can look for. model number 48 HJF 012 571HQ thank you for any help.

[ACFIXR]

Check your voltage drop to contactor. Check conductor size.

[invisiblecollar]

Sounds like a bad contactor coil to me.

[garytulsa]

i have high voltage and good low voltage to contactor and its not just one contactor its both compressors and outdoor fan contactor

[KY-kid]

i have high voltage and good low voltage to contactor and its not just one contactor its both compressors and outdoor fan contactor

I am not the greatest trouble shooter for sure - but if you have good control voltage, and the coil is not engaging enough to close them, I would think either something wrong with contactor coil -- or more probable as you said someone suggested in your previous post Loose connection somewhere-- possibly the board has a setting of higher than 5 minutes before it can be turned back on ???

[garytulsa]

I have 3 contactors and all of them are not fully engaging. I did ohm out the contactor coils and they tested good. I am getting good voltage at the relay. I didnt ohm out its coil. Today it ran fine. Seems like every other day and up to three times a day i have to pull the disconnect or just push in the coils. i will check out the line voltage at the disconnect and see if i am gettin a full 440. I am not sure where to go from there. thank you for your help so far.

[sdtech]

Most Carrier unit there is Compressor lock out circuit board for each compressor sometimes unit wont come on when its call for cooling your circuit is open check that first. good luck

[DavyB]

Wait, What? Is this a question, or are you teaching us something??

EDIT: Sorry, my browser popped up with thread #7 first sorry 'bout that.

[DavyB]

Sounds like a bad contactor coil to me.

Sounds like low line voltage to me. time for a new transformer?

[garytulsa]

Not tryin to teach anything dave. I will recheck the components mentioned. Thank you for everyones help. It almost seems like weak magnets but on all three contactors? And the issue is not constant. I am just out of school and starting to see how much I dont know lol. again thanks for everyones time. glad i found the site.

[alpha480v]

Sounds like a low voltage problem. One contactor, maybe contactor problem. All three, possible voltage problem. Could be Clo problem also, they act up alot on Carriers.

[hands]

i have high voltage and good low voltage to contactor and its not just one contactor its both compressors and outdoor fan contactor

Just so I have this right. With a call for cooling you have good low voltage at the contactors but they are not pulled in. If this is the case, I would replace one of the contactors and see if it works.
Are you sure you didn't check the voltage at the contactor while it was pulled in?

[VTP99]

First this is a 10 ton unit.
Second fallow the advice of Davy post #9.