[ifIknew]

3.5 ton 50 amp compressor Tripping The Breaker on start.
C-R381 C-S255 R-S 128
149ohms lowest TO THE FRAME
I don't want the compressor to be Bad but it is looking that way. what do you guys Think?

 

[HVAC_Marc]

It's shorted internally or right under the compressor jock strap.

 

[catmanacman]

Any resistance to ground is bad

 

[timebuilder]

3.5 ton 50 amp compressor Tripping The Breaker on start.
C-R381 C-S255 R-S 128
149ohms lowest TO THE FRAME
I don't want the compressor to be Bad but it is looking that way. what do you guys Think?

If you took the readings correctly, yes. It is "bad."

 

[Airplumer]

From your readings yes shes gone

 

[heatingman]

I concur. If those readings are taken with a ohm meter - and you have ohms to ground - its done for sure.


Sent from my iPhone using Tapatalk

 

[Warmaire]

I thought we were not supposed to teach DYI if he doesn't know then he/she has no business messing with it

 

[HVAC_Marc]

I thought we were not supposed to teach DYI if he doesn't know then he/she has no business messing with it

This is tech to tech-residential. we are assuming the guy has an inkling of what's going on. It *could* be a greenhorn with little knowledge about compressor electrical internals. cut the guy some slack, you had to start someplace, too...

 

[kdean1]

Bad compressor, no doughnut!

 

[heatingman]

Bad compressor, no doughnut!

Or no doubt.


Sent from my iPhone using Tapatalk

 

[icy78]

Bad compressor, no doughnut!

Or: doubt not

 

[napple]

It depends where your taking your readings from.
If your reading from compressor terminal to ground then compressor is at fault
If reading with wires still connected you could have short thru wiring or even crank case heater (depending on how its wired )
if compressor is truly shorted to ground, take steps to clean system of acid before replacing the compressor

 

[aquadave]

is this a package unit with elec strips? if not why do you have a 50 amp breaker on a 3.5 ton condenser? did you isolate the compressor completely? So you're sure nothing else is shorted

 

[buttwheat]

3.5 ton 50 amp compressor Tripping The Breaker on start.
C-R381 C-S255 R-S 128
149ohms lowest TO THE FRAME
I don't want the compressor to be Bad but it is looking that way. what do you guys Think?

If you are taking your ohm readings correctly (no wires hooked up to the compressor) then there is no question, it gone

 

[JonnyD0331]

take the wires off first and take another reading.
your C-R S-R C-S readings all add up and "look" like your compressor might be alright.
Try disabling the contactor by pulling the 24v common off- cycle unit power- see if it trips the breaker.

Also if you are tripping the breaker- I always check the condenser fan motor wires first. Condenser fans tend to blow alot faster than compressors do.

items to check: Always remove wires first
condenser fan motor
capacitor (yes it can ground a 50A breaker)
crankcase heater
compressor
compressor contactor.