Compressor issues

[aca carwash 2]

Before I get called out again, I called an electrician and paid $250 and compressor still not working.


3 phase

Compressor was running all the time and kicking breaker, pressure switch was leaking. replaced the pressure
switch before I realized the check valve was bad,replaced the check valve and the pressure switch with one that's not adjustable.
in other words could not adjust the variable of on/off cycling. the previous one was adjustable. the new one cycles from about 100-107
psi.

the breaker was still kicking 3/4 times a day. replaced the breaker. Didn't kick for a month, now kicking 3/4 times a day again.

trying to find out if its the contactor or need another pressure switch that cycles less around 110-150 psi, how can I test the contactor? Do you think its the pressure switch? coming on 5/10 times an hour.

Happy Thanksgiving!!!!!

 

[Eric H]

I'd start by confirming that the motor is spinning in the proper direction. then check that there isn't some sort of mechanical issue, belt too tight or too loose and both pulleys are in the same plane, oil level correct, etc
After that, get a clamp on amp meter and measure the amp draw on each leg to confirm that you have the properly sized breaker and wire. Compressors have a huge startup amp draw (called inrush). when I installed my last compressor the manual called for a 30 amp breaker, we ended up with a 50 amp which required replacing the wire from the panel to the compressor.
Are all of the wire connection tight and wires undamaged? a loose connection can overheat the wire which over time will increase resistance which could cause a breaker to trip. Damaged wires, including broken strands from improper striping or over tightening lugs, can also overheat the wires. Are there areas on the wire casing that are burnt or brittle?

5-10 on off cycles per hour seam like a lot! is there an air leak (or several small leaks) somewhere? Turn off EVERYTHING in the equipment room including the lights and listen for a minute. Small air leaks are a huge energy waster...but now we are getting a bit away from your original concern.

It's hard to diagnose these issues after Thanksgiving dinner while enjoying another glass of whiskey!

 

[MEP001]

Start with the simplest things first - when is the last time you drained the tank? Too frequent cycling could make it trip.

It could also be the motor failing.

 

[JGinther]

All of the above is right, but I'm betting you got the wrong part. 170 (I'm guessing that's what you meant to type) is probably too much for the compressor ratings... Too much pressure is too much current... Snap.

Do you have the old pressure switch? Sounds like you replaced it when the check valve was the culprit.

 

[MEP001]

All of the above is right, but I'm betting you got the wrong part. 170 (I'm guessing that's what you meant to type) is probably too much for the compressor ratings... Too much pressure is too much current... Snap.

Do you have the old pressure switch? Sounds like you replaced it when the check valve was the culprit.

I'm assuming that a compressor with a 3-phase motor is a dual stage unit capable of reaching 170.

 

[Kevin James]

Did you replace the tank check with the right tank check? I’ve replaced some tank checks that were bad out of the box. There was probably nothing wrong with the pressure switch you took off, I'd put it back on. You always want to use the same pressure switch that you took off. I always have a spare pressure switch on hand, you never know when one is going to go bad, like on a Friday night before a busy weekend. Take you clamp on Amp meter and check how many amps each arm is drawing, you might have a bad motor. Report back!

 

[aca carwash 2]

it cycles all the time because its only a 7 psi on off cycle

 

[aca carwash 2]

yes, the old switch cycled around 130 and 170 psi I believe

 

[JGinther]

it cycles all the time because its only a 7 psi on off cycle

So you got me confused again... If its tripping at only 107 psi ( I guessed you mis-typed 170 earlier), then its time to learn how to use a clamp-on meter or get a better electrician. Or better yet - a proper repairman. Oh, and this time, pay him AFTER its fixed. You sound very nice, to the point where I'm thinking about sending a bill for my worthless time here... (I'm joking.... Or am I...?)

So many things can cause that problem, that stabbing at it could get very costly... Less than just buying a new compressor. With clear details, though, were here to help.

 

[mjwalsh]

yes, the old switch cycled around 130 and 170 psi I believe

aca,

It seems like you may want to examine what the label or documentation for the pressure switch says. They should have the turn on psi & turn off psi. That is the differential. It appears to be not performing correctly differential wise??? Based on actual experience ... the more often the motor starts up the more likely it could start to overheat etc & possibly blow a breaker. Something to consider.

 

[aca carwash 2]

How do you upload pictures to this forum?

 

[I.B. Washincars]

It’s extremely clunky and difficult, but can be done. if I remember correctly, you will need to click on the “insert image” box. It will ask for a URL, which you wil not have. It’s fumbling around from this point. I think you will need to click “go advanced”, then scroll down to “manage attachments”. You fumble around in that area to get the job done. Sorry I’m not more help than that, but it’s 10 times as hard as it should be.

 

[Waxman]

Uploading pics needs to be better and easier!

This website would be much better and more enjoyable if it were simple and easy. We all carry cameras now and we have lots of cool things to take pics of and post here. But we don't do that very much because it is clunky! Lets get with it!!!!!!! Look what it does for facehole ( what i call facebook).

 

[MEP001]

I use Facebook for hosting images now, just click on your username, then Photos, then Create Album, then upload a photo. Make sure you set the album to public, then once the photo is uploaded right-click and select Copy image URL and paste that to the forum with the Insert Image button. After that select Albums and the new hosting album to upload more.

I doubt your old pressure switch is bad. Unless it was leaking the only other thing that is likely to fail would be the contacts, but since you have a separate contactor there's no load on the pressure switch so that part is not likely to fail. With only a 7 PSI differential it may be cycling too often and just getting hot.

 

[I.B. Washincars]

I use Facebook for hosting images now, just click on your username, then Photos, then Create Album, then upload a photo. Make sure you set the album to public, then once the photo is uploaded right-click and select Copy image URL and paste that to the forum with the Insert Image button. After that select Albums and the new hosting album to upload more.

That doesn’t sound cumbersome or clunky at all . I tried the FaceBook thing and couldn’t get it done that way either. Geeks just don’t seem to understand that what is child’s play to them can be confusing as hell to the average joe. I could possibly accept that that is just the way it has to be, but I’m on several other forums that are very easy. This is the hardest one for posting pictures.

 

[MEP001]

I'll post a step-by-step for using Facebook along with pictures. I felt it was very cumbersome the first few times I used it for uploading/hosting images, but after doing it a few times it's easy. Once you create an album you can just shortcut it, then you're uploading with one click. There are very few ways you can upload a full-size high detail image for free hosting. Google Drive was one and it was very simple, but they no longer allow forum image linking.

 

[Ghetto Wash]

How do you upload pictures to this forum?

I have uploaded this pic directly to AutoCareForum.com and have included it in this post. This pic should give you all the info you need to do the same.

 

[wash4me]

Post wire size motor fla, motor service factor, breaker size, voltage. Put your old pressure switch back on as others have said it's probably fine. Get a clamp on amp meter and put it around all three of the leads going to the motor and post the amps. Leave meter on one wire until the compressor kicks off and note the amp reading at the low pressure when it kicks on and the amp reading just before it kicks off at 170.

 

[MEP001]

Get a clamp on amp meter and put it around all three of the leads going to the motor and post the amps.

I assume you meant to put the amp meter on each of the wire leads one at a time to read the current draw. Putting it around all three at once won't show anything.

 

[br549ms]

The cut in it 130 psi and 170 cut out, that's a 40 psi differential? if it is cutting on at 130 and off at 170, the pressure switch is working. If not the pressure switch is not working or not set right.

Sound like it is working, just cycling to much. You may have a tank full of water, like someone stated before. You may have several leaks causing air pressure to drain to rapid.

If this has been going on for some time the motor may have been damaged by the constant cycling and tripping of the breaker. Like MEPOO1 states put the clamp meter on and check the amps on each lead individually, if three phase - all three should be almost identical.