electric scheme

I don't have the schematic with me so please tell me what the problem that you have is and I'll see if I can help you out.

Don

I have four of them.

THey have several problems.

I couldn't open the door.

Compressor doesn't work

Timer doesn't work

OK, lets deal with the obvious easy stuff first.  If the timer doesn't work, then the timer has failed.  The bad news is that the vendor that Beckman used for the timers stopped making them about 10 years ago so unless you can find a suitable substitute then you will have to manually turn it on or off but just using the always on position to turn it on and then turn it to the "0" position to turn it off.  There's really nothing else that I'm aware of that can help you with this problem.

Door issues can be more problematic.  It all depends on what has happened with the door latch.  There should be a small access hole on the right side of the top cover near the door latches position.  If you take a sturdy paper clip that has been straightened out, you can insert it into the hole and push the release mechanism out of the way so that the door can be opened manually.  Door latches fail on older model centrifuges such as the J2-21.  There is a replacement for the latch but it requires some reworking of the top cover.  If the handle has come free of the latch then you are really in trouble.  There's more that can be discussed but first I need to know where the trouble lies with the latch.

As to the compressor not starting, there is a black capacitor box down near the compressor.  There are two capacitors and a relay in the box.  Typically, the start capacitor fails and it will be pretty obvious if that is the case.  Next will probably be the start relay failure followed by the run capacitor.  Any or all of these parts can be replaced.  If none of these components has failed then you probably have a compressor failure.  You can check the windings of the compressor by checking between the common terminal and both of the other connections on the compressor.  These values should be very low BUT they should NOT be shorted out.  If the compressor has failed, then you will probably be faced with a major repair bill.  The original compressors are not available anymore because of the type of refrigeran that they used.  You can replace the compressor with a newer version compressor but you will also need to replaced the parts in the capaciotr box because the newer compressors require different component values.  This is not an insignificant repair operation even for factory trained engineers such as myself.

Sp, you now have a starting point but you are dealing with very old, but usually reliable technology.  Understand that many of the parts used in the J2-21 centrifuges are no longer available through Beckman or any other sources.  This probably means that you may have to canabalize one or more of your centrifuges to keep the others functioning.

Get back to me on this site and I will try to help you out if I can.

Don

Thank u very much

We figured out the problem with the door and compressor

Now we have other problem. Centrifuhe is not running when we push start button. We fought problem with engine and took other engine from the working centrifuge but that engine didn't work either 

I think problem in start button or in wiring. Can u help me with this problem

P.s Sorry for my english. It is not good so maybe I couldn't explain u my problem clear enough

I forgot to say that problem with copressor is. There was a leak of freon so it is not cooling.

Do u know the type of freon this compressor use? F12 F134 F22or some other

And one more spindle not spinning how to solve this problem?

Don't worry about your English.  As to the drive MOTOR not starting condition of the centrifuge, the problem could most likely be one of the two door interlock switches.  There is one switch that is activated when the eyebolt on the chamber door pushes down on the switch that is located under the plastic cover that sits over the door latch assembly.  The other switch is located at the very rear of the door latch assembly but it sits underneath the top cover assembly so access is really quite limited.  The only way to get to the switch is by releasing a screw that is accessed by removing the lower front access panel.  Up underneath the right front of the centrifuge is a triangular opening.  There is a screw that secures the top cover at the top of this opening.  It is a VERY tight fit so you will need someone with fairly small arms to be able to reach up with a socket wrench in order to remove the hex head screw.  I believe that it is a 3/8" standard head screw.  After it is removed, you can then lift up the right front corner of the top cover AFTER you have also loosened the door latch assembly.  You can then check out the operation of the door latch switches.  You should know that there was a MAJOR update of the door latch assembly from the old style to the last version.  The old style latch is no longer available.  The new style fits in the exact same position but there can be issues getting a replacement latch installed.  We will deal with that if/ when that becomes the issue.

If the door latch switches appear to be operating properly, it still does not mean that the door latch is not the problem.  The door latch swich that is not physically attached to the latch assembly can sometimes require adjustment after constant usage.  Typically this requires reorienting the switch so that the contact arm makes closer contact with the eyebolt when the door is closed.

Please check these items out and get back to me.

Don

The freon that is used in the old J2-21 centrifuges was NOt any of the types that you referred to.  There should be a label on the back of the centrifuge telling you what type of coolant it uses.  Sorry, but it has been way too many years since I worked on one to tell you the exact type of coolant.  If you cannot find the label, let me know and I will ask some of my old coworkers for that information.

Where exactly is the leak that you found?  Frequently, the schraeder valve body in the low side access valve is not secure and over time, freon will bleed out of the fitting.  Sometimes just slightly tightening the valve will fix the leak.  Hopefully, the compressor was not run so long that it has caused a burnout of the compressor.

Don

Thank u very much I did what u said and everything is working :)

I couldn't find any label about coolant type but i will try to find it tomorrow.

Any way as i could understand that type of coolant is not producing now.Can use another type of freon? Should I change the oil type in compressorfor that?

I didn't find any leak yet but when I oppened front acces panel there was oil spots that is why I decide that there was a leak. After that I found a tube from which I guess freon is fueled so i took off a cap and push a nipple there was't any freon that is why I am sure what there is no freon in the system