York Affinity 3S Kicks Breaker when Starting

I have a York Model YZB03611B A/C-Heat Pump unit running R410A that will kick the breaker at the box when the compressor is supposed to come on. I replaced the Starter because the contacts on the old one were melted. I checked the compressor resistance at the plug on the compressor (pulled the plug off it) and found the compressor ohms to be 1.66-1.68 Ohms on the start winding and .6 to .7 Ohms on the main winding. From what I could find out, this was what it was supposed to be. I found no ground between either winding and ground or each other. I had infinity. I checked the capacitor (dual cap) and found it to be OK. The motor never tried to start, it didn't hum, it is almost instantaneous kick. I did not find anything wrong with the condensing fan when I ohmed it either. I also checked compressor wiring back to the local disconnect and found no ground on either leg.
During the winter when I was working on the house (House is in trust and I'm preparing it for future sale) I noticed the condensing fan would start and stop. Sometimes it never came on and the emergency heat would kick in (breaker downstairs wasn't kicked, so I assumed it was internal compressor breaker took it out). I only noticed it wouldn't work at all when it got hot this summer when I was there and tried to make it run.
Questioning my parents about it after looking at the compressor and noticing it had been replaced before (looked like a mud dobber had done the brazing) they said they had it worked on about two years ago. No one has lived in it for a year now, so the compressor has probably only had one hard season on it and one other winter.
My question is this. Is it possible that the previous repair individual did not put enough oil in the system and compressor is locked up? How common is it for a Danfoss HRH032U1LP6 compressor or any scroll compressor I suppose to freeze up mechanically?
Is there anything on the mother board that could cause a trip? I disconnected the compressor but the starter would not pull in (at least the condensing fan did not start, perhaps it wasn't supposed to until compressor starts?). But when compressor is plugged back in breaker kicks.
Is there any other test I can do to determine something else?
What have I overlooked?
I'm certainly not a refrigeration tech, but as a Mech E. I have fooled with them all my life. I know the cycle, and what the parts do, but am certainly not versed in the inner workings and hidden mechanisms of the units. I have gauges, vac pump and tank, but I see with the R410A all are useless.

 

Welcome to the forums.

You have a heatpump. In the winter.... the defrost board controls the condenser fan. If it's too cold outside.... the condenser fan could shut off or cycle. During a defrost cycle..... the fan may shutoff or cycle and the electric heat coils are energized to keep the house from cooling. Technically a defrost cycle is running the unit in A/C mode which dumps cold air in the house.

What are you measuring with ? Your values are a little on the low side but resistances vary widely.

Typical values......
R to C -- 3 ohms
S to C -- 6 ohms
R to S -- 9 ohms

 

After measuring the values, I found the Danfoss website and downloaded the info for the compressor. The values I measured are what the manufacturer say they should be.
I have a Fluke digital meter and a Simpson analog and I tend to use whichever will give me best reading for whatever it is I'm doing. I used the Fluke Digital on this. I used the Simpson to test the Cap.
I know it's a heat pump, wasn't thinking it was a defrost cycle though. Learn something all the time. I know what the reversing valve does, and how the system works. Just never thought of it as defrost cycle. But it would defrost the coils huh?
When I say the fan was stopping and starting, I mean it wasn't coming to a stop before starting again. It was surging almost. I thought it strange when I was looking out the window at it, but didn't think much of it till I noticed the gas was running a lot.

D

 

Usually when the breaker trips immediately on a call for cooling it indicates a winding short to ground. You said you didn't measure any continuity from ground.

If the compressor resistances are within spec. I would disconnect the compressor lines from the contactor and on a call for cool see if the breaker still trips. If it doesn't trip it could only mean that the compressor is frozen internally.

The specs for your condenser state 25.6A minimum circuit ampacity which means it requires at least #10 wiring. It also says 40A maximum overcurrent protection device. Typically a 30A would be used but in this case you should be using a 40A breaker.

 

I don't remember the breaker size off hand, I'll check it. The wiring is #10 THHN I believe.
I'm going to do one more round of ohm checks, and I'll take my megger and double check to ground. I think I've got a 300 v setting on it, been a while since I've used it.
I've found a replacement compressor for a little over $500.00, but this R410 pressures are over what my gauges are rated for, so it looks like I'm in for an equipment upgrade too. SIGH, It's always something, there is no rest for the weary.

Thanks for your help.
D

 

You shouldn't assume that if there's a short, it in the compressor or fan.

It could be anywhere.

Start by checking resistance between contactor (switched side) high voltage terminals and ground.

 

I checked those when I replaced the relay. I found nothing to ground on the either side of the contactor. When I unplugged the compressor, and turned the power on it did not kick the compressor. I'm not sure anything at all happened, but it did not kick. As soon as I plugged it back in the breaker kicked.

D

 

You have positively confirmed that the problem is solely the compressor.