A/C Repair help

[insaneracin2003]

Hey everyone, I am having issues with my AC Unit. I replaced the fan motor and run capacitor in the condensor outside last year about this same time. Last week the fan quit working again and I changed the motor and cap again...Now it only lasted 1 week and the fan motor stopped working again last night. My outside unit seems to have 2 capacitors. I only changed the 1 small one that I was told to change when changing the motor. Should I try and get the other Capacitor changed?? I am not sure what it is for. It sits right next to the run cap but is a lil bigger. Can someone help me as I am concerned about this since my wife will be having surgery on the 31st and I need to make sure she is as comfy as possible during her recovery...Thanks and God Bless

[DnB_racing]

is the motor a multi tap motor?and are you absolutely sure the motor is wired for the proper voltage?

what type of motor are you replacing it with,and is there anything bent on the shaft or pulley that could be causing bearing failure?


I would meg out the motor first to make sure the motor is bad.and clean the fins in the cooler to make it easy for the fan to work... then when running take an amp reading and see if it exceeds the tag amounts

[insaneracin2003]

Originally posted by DnB_racing
is the motor a multi tap motor?and are you absolutely sure the motor is wired for the proper voltage?

what type of motor are you replacing it with,and is there anything bent on the shaft or pulley that could be causing bearing failure?


I would meg out the motor first to make sure the motor is bad.and clean the fins in the cooler to make it easy for the fan to work... then when running take an amp reading and see if it exceeds the tag amounts
Not sure if it is multi tap, but I did get the information off of the old motor and brought it all to Grainger. I replaced it with a Dayton motor and run Cap. I was talking with someone and they said to make sure the fan is mounted to manufacturer specs. That is what I will check tonight...Thanks for the help.

[HondaPohl]

Check to make sure that mice havent started chewing through the control wires that run back to the thermostat and air handler. Ive had that already.

[DnB_racing]

Originally posted by insaneracin2003
Not sure if it is multi tap, but I did get the information off of the old motor and brought it all to Grainger. I replaced it with a Dayton motor and run Cap. I was talking with someone and they said to make sure the fan is mounted to manufacturer specs. That is what I will check tonight...Thanks for the help. the reason I ask is it could be wired for the wrong voltage,,,

many motors have different winding taps for different voltages,

what are the voltage readings on the motor tag?
its possible you might have to move an internal jumper on the terminals, to wire it for the proper voltage


a Dayton motor should last a long time, i would double check to be sure its wire right for the proper voltage

[smr]

the other capacitor is your start capacitor. Wouldn't be a bad idea to replace it also.

Most likely if you wired it up for the wrong voltage it would have died out in the first few hours.

Have you cleaned the condensor? That is the #1 reason for the motors to go out. If you condensor is dirty then the fan can't pull the air through and this over works your motor.

good luck

[DnB_racing]

Originally posted by smr

Most likely if you wired it up for the wrong voltage it would have died out in the first few hours.

not always, it depends on the load,a 220 motor wired 110 with little load will run until the load increases enough to increase the amps, ohms law tells us the higher the voltage the less the amps

the motor will run on any of the voltages its the amps that create the heat that will overload the motor, but like you said dirty the fins in the condenser will increase the amp reading, and cause heat, both could cause the motor to overload,

a quick amp reading will answer many questions for the OP

or it could be a belt that's overly tight pulling pressure on the bearings, or if its direct shaft a bent fan blade causing the same,

but for any of these problems you can get amp readings and it will help answer what's going on

[outacontrol]

bigger capacitor is for the compressor, small one for the motor. almost all residential ac units are 220 volt. Confirm your motor is 220v. Other than amp draw, make sure the rotation of the motor is going in the right direction (blowing air up in your face), ive had brand new ac units out of the box, with the motor rotating in the wrong direction. This would cause compressor overheating and possible fan overheating.

[mxduner]

hope you already found the problem. But have you checked the actual voltage coming into the condensing unit? or even in to your house? it is not uncommon for the transformer to over fead you voltage. Just seen a guy burn up his 220 air compressor, then 2 weeks later his big welder. had like 260v coming in lol.