06e compr trips breaker

[realjd]

have 25hp 06e compr; suct78 disch 250;one unloader suct cutoff;
compressor runs for approx 8 mins then breaker to comp trips;sorry,at time didnt have amprobe to ck amps.
this unit was running ok couple weeks ago,no probs.
found this when i returned to work to ck system
i can front seat suct valve unit runs ok.
any suggestions?

[txhvac]

If you can run the compressor w/ the suction svc. valve closed does it pump into a vacuum? 20" or so. Your not locked up, an amp draw would be helpful, the breaker could be going bad, is the breaker warm to touch? Can you swap breakers & see if another one will stay on line? Is all your electrical tight & clean? Unloader mechanical or electric? Are you starting unloaded? Hope this can help.

[realjd]

thanks for ur help

[realjd]

unloader mechanical;
will try and get amprobe to ck amps;yea,thought about breaker being bad
comp only trips now when suct valve open more than half way; seems like when it loads up it trips breaker. oh, liq line s.g. bubbles- little low charge? i will try and get s.h. and sub cool readings. 2 wks ago super at comp was around 20 and sub cool was 15.

[clgman]

The breaker that trips, is it the breaker which is part of a Carrier unit, or it is a breaker part of a built up service panel ? If it's a Carrier breaker, they are typically rated for "Must Hold Amps" and "Must Trip Amps". Be sure of the actual current draw and test the breaker. If the breaker(for whatever reason)was used for repeatedly stopping the compressor during operation, it could be bad. Also, be sure all the connections are clean, tight, and secure without any carbon tracking, that includes inside the motor terminal box. Continue to measure the voltage and current when you think the compressor is about to trip the breaker. You should also be measuring oil pressure and observing what is happening in the oil sight as the trip is about to take place, and what the operating pressures are. Good Luck !!!!

[joepaul]

Just a thougth, check your oil pressure, oil level, discharge superheat,return gas temperature, temperature on the motor barrell from top to bottom and the temperature of the oil sump below the oil level. Carlyle publishes what all the readings should be and what they mean if they are out of range. You can get this info from there website.



We had an o6D with flood back, a bad CCH and a severe overcharge last year. System was fixed orifice. By the time we got the call the oil pump had been pumping refrigerant instead of oil and it damaged the main bearing on the motor end (you know, the very last item to get oil from the source). After about 45 minuites of run time the breaker would trip.

Joe

[tjc76]

does the suction line vibrate erratically when the compressor runs? i' ve had the same problem with carlyles very recently. unit runs for a few minutes, then trips breaker. you need your amprobe my guess is you have a busted rod or crankshaft. 3 different units, busted up cranks, caused by high compression ratios.

[clgman]

have 25hp 06e compr; suct78 disch 250;one unloader suct cutoff;
compressor runs for approx 8 mins then breaker to comp trips;sorry,at time didnt have amprobe to ck amps.
this unit was running ok couple weeks ago,no probs.
found this when i returned to work to ck system
i can front seat suct valve unit runs ok.
any suggestions?

So what did you find ?

[Jabarco]

sorry,at time didnt have amprobe to ck amps.
any suggestions?

Hey, we can't help it if you don't have an amp meter!

[chiller mekanik]

Hello,

You may want to take a look at the oil pump/bearing end. Sometimes this bearing can wear out & you can tell by the temp rising as the compressor operates, the hotter the bearing, the higher the amps.

This is of course after you've taken all of the good advice thats been given so far to prove what the problem is not.

If you decide that the bearing is the problem, replacing the bearing only has about a 50% success rate. So, the question is: is it worth it? IMO, yes. You have to weigh the level of difficulty in replacing the compressor with the cost against the bearing replacement cost factored with your (or your boss) comfort level of the taking the risk.

Good luck!

[hvac_czar]

Condenser coil (s) clean? Check pressures and condenser fan operation. Dirty coils sometimes show up on RTUs as breaker trips on equipment that had been "fine".

[atmosphere]

And how much make up air air you using?

[realjd]

does the suction line vibrate erratically when the compressor runs? i' ve had the same problem with carlyles very recently. unit runs for a few minutes, then trips breaker. you need your amprobe my guess is you have a busted rod or crankshaft. 3 different units, busted up cranks, caused by high compression ratios.

yea,busted rod on comp. changing with new txv and unloader,plus new drier cores. i noticed another comp on another unit,same model without unloader (pressure unloader). Is this ok,or should i add an unloader to this comp.


thanks for all your replies.