york dirty filter - clogged filter YSDBC

[socal13]

OK, changed filter, ran chiller @ 50% pull down for 30 min. Meanwhile display reads dirty filter, which I know I changed out the day before. Now I know by reading invoice copys from the previous maint. co. (york) ,that this is an ongoing issue. When the pulldown time expired and it loaded up it shutdown on clogged filter. According to thier records they changed out filters and transducers, and this seems to be a problem machine. From the scraps in the control panel it looks like they changed out the eproms at least twice. OK my question is ... could this be a control board problem ?, or could the oil cooler be kinda restricted and and causing a high pressure differental on the transducers ?

[klove]

Check your compressor. On the control panel side, about (+/-) midway of the compressor body, if there's an oil line with a service valve on it, shut it off. This is the oil injection to the rotors. There's enough natural oil flow thru this compressor that it's not needed. Unrestricted flow thru this line causes such high flow rates thru the filter that it creates a "false" high pressure drop thru the filter, thus triggering the clogged oil filter display. If you're not comfortable shutting it off, frontseat the valve,crack it off the front seat, start the compressor, and with the load stable and slide valve not taking load or unload hits, set your filter differential at about 4-9 psid by adjusting the valve. Obviously, before you do this, make sure your transducers aren't lying to you. GL

[socal13]

Is this a standard operating procedure ? Is it in documentation ? I know exactly the service valve you are talking about. Why would they install this oil line if it was'nt needed?

[klove]

Those are all very good questions. First, no, there is nothing in documentation to that effect (I would say "Trust me", but you don't know me from Adam's housecat). Because of the problem that came up on this compressor, yes, it is SOP. If you have any of the newer YS's around, you'll see that they don't have the oil injection line, but they're the same compressor. According to York engineering, there should have been an orifice at the input of the injection port so that no matter how far you open the valve, you can't go past a certain flow rate, but for whatever reason, they didn't do that. That's why I threw it in about not closing the valve completely but adjusting it to a reasonable amount of input. Reason for the line in the first place is this is just an upside down Frick screw, and it was just a normal course of engineering to design oil injection into the compressors because on most refrigeration applications, it can get to be a necessity. On these chillers, at a/c temps, the gas densities and velocities are such that there is a lot of natural oil circulation in the system which does away with the need for rotor injection. Just set it, don't shut it off if that makes the pucker factor go up too high.

[socal13]

There is a little history on this machine beyond what I prevously explaned.
The service valve you point out was closed off to give a 11 psid reading for the filter , according to the log book, which had only one set of readings ,when we took over this contract. Of course my co worker and I, upon seeing this valve closed off ,thought that someone who tread before us forgot to back seat it. Now, this chillers twin , that sits next to it ,has the same valve fully backseated and runs with a 8 psid on the filter. more to follow.

[frick]

there is a mathmatical formula that you can use to see if the micro is calculating the psid right also sorry I do not remember how to do it, call the factory 800-838-7219 they should help you with this matter?? If i can find the formula I will let you know

[frick]

There is a little history on this machine beyond what I prevously explaned.
The service valve you point out was closed off to give a 11 psid reading for the filter , according to the log book, which had only one set of readings ,when we took over this contract. Of course my co worker and I, upon seeing this valve closed off ,thought that someone who tread before us forgot to back seat it. Now, this chillers twin , that sits next to it ,has the same valve fully backseated and runs with a 8 psid on the filter. more to follow.

is ther a filter installed on the side of the compressor (balance piston) area

[MrYork]

KLOVE and Frick hit it right on the head, close the said valve then check your condenser approach, high pressure will also cause nuisance trip's.

[socal13]

Frick, there is not a filter installed on the side of the compressor. Shaft seal does need replacing though. I pulled the oil pressure and filter transducers and confirmed proper operation.
Changed the filter and ran chiller, with valve fully backseated ,Filter PSID showed 5 psid. Chiller backed off on low water leaving temp. when it came back on line the filter psid shot up and it shut down on clogged filter.
Before I changed the filter and checked transducers ,I had the afore mentioned valve closed down to where it made me a little uncomfortable, and the psid gradually climbed back up to the shutdown state, 25 psid, >5 sec.
MrYork the Condensor approach is 3 degrees

[klove]

There is a little history on this machine beyond what I prevously explaned.
The service valve you point out was closed off to give a 11 psid reading for the filter , according to the log book, which had only one set of readings ,when we took over this contract. Of course my co worker and I, upon seeing this valve closed off ,thought that someone who tread before us forgot to back seat it. Now, this chillers twin , that sits next to it ,has the same valve fully backseated and runs with a 8 psid on the filter. more to follow.

Starting from this point, if you haven't already, do 2 things. One, make sure you have the same oil filter in both machines - should be 026-32831-000. This is a 3 micron filter. There are lots of filters that will fit that York has sold over the years, but this is the correct one. It gives plenty of protection to the seal and brngs, w/out excessive DP (this MAY be the other chillers thing - it could have a 10 or 12 micron filter in it, which would drop the DP). Two, go into service program and make sure that "auto zero" is enabled on your oil and filter pressure transducers. This will zero the error between the transducers during prestart as long as they're not too far out. This could also have something to do with the DP reading on the 2nd chiller. Never trust your reputation to an instrument that sits on a vibrating piece of machinery all day.

Another thing to remember is that your DP will go up drastically (albeit momentarily) when you take a load hit on the SV solenoid. This is because that hydraulic cylinder takes a BUNCH of oil to move it. You have a 2 second resolution on the one-line micropanel (I think that's the one you have), and you can get into a resolution cycle sometimes that will make you see things that aren't there, or vice versa, during this period. This could be the cause of your startup DP going high when it takes that initial load hit to get the SV to it's minimum position. Which brings up another point - what's your SV % readout? Is the SV pot working? If not, you could be throwing this thing into a constant load condition at startup, and the DP wouldn't drop off 'til the SV was completely loaded, or current limit killed your load signal.

Don't be afraid to shut down the oil injection if need be. Close down the input line to the load side of the slide valve cylinder to slow loading if need be. And, if this machine has the duplex oil filters, there's a lot of DP through that commuter valve setup on top of that thing. It may be that you're developing a problem there. Let us know how things turn out. Hope one of these things gets you on the right track.

[MrYork]

If your shutdown is happening right after startup than forget about what I said about high discharge pressure maybe being a cause. I'm not sure what style of machine your working on. If your working on a style c than there is a solenoid valve on the oil supply line right after the oil cooler if this solenoid valve is sticking (unlikely) this maybe your problem. There is a capacity control block on these machines n the style c the block is on the top of the compressor. You may be having a problem with this block, If your trying to load and port sc which should closed at this point open than all your oil is shooting right back to the compressor. This block can be isolated so troubleshooting shouldn't be hard. Once you take off the 4 hex screws the block comes apart then using the service mode load and unload this valve. Using a straw check which ports are opening and closing.

[it's me]

So Cal


I realize that this is an old thread, but I'm a little slow. Was wondering if you ever got to the bottom of this problem. I'm sure by now you have, but did not see a final outcome.

The reason I ask is because I had a very similar situation a few years ago, and although the suggestions posted were great ideas, they did not work for me at the time. It was a very strange phenomenon that had me puzzled for days and the thing that finally worked out (I stumbled upon ) I still can't explain.

Let me know what you did to clear your problem. . . just curious

[socal13]

front seated the valve aforementioned , to 9 psid. All the way shut gives a 4 psid reading. Exact same chiller next to it has the same valve open all the way and runs at the same psid. York needed to put out a service bulletin for this issue.