New to forum. York Ycas CODEPAC problem High oil temp
having problem with high oil temp. replaced plate and frame oil cooler with larger cooler. run unit at 26 degree outlet setpoint. problem occurs when slide valve goes below 30%. have calibrated slide valve and checked sensors. amk running unit at 45% load to keep unit from tripping on oil temp and is cycling on LWT-auto restart. not doing motor and starter a lot of good. have checked freon to oil cooler and where is located(downstream of orifice on bottom leg from condensor to evaporator i would think it has to be full of liquid. Good filters on oil line(changing every few days) to try to make sure i have good oil flow. oil pressures look good and so does oil differential. HELP
I'm not familar with this chiller, but this statement makes me suspect low water flow. Are you having to change oil filters so frequently because of pressure drop, or is it just an effort to reduce high oil temp trips? And does it help? You could have multiple problems. I like to start with bringing the machine to design conditions (such as water flows) and go from there. Running outside of design specs can sometimes create unexpected problems, and troubleshooting those problems while outside of specs can be an exercise in futility. But like I said, I'm not familar with this chiller.
Originally Posted by guess1956
have been told unit from factory has problem running at these "low" temps. lowering head pressure to 150 has helped. started at 180psi. thought about installing expansion valve on freon feeding oil cooler. unit "i believe"was designed from factory to run 50-60 degree temps. am changing filters to elinate any oil flow problems that i dont believe we have. the changing filters does not help. pressure drop trips at 26# and am running 14#
delta t across condensor varies as cooling tower feeds various exchangers in plant. most delta t i get is about 20 degrees
i guess i could write all on one post. the cooling water temp is about 70 degree entering
welcome to the forum! (i will now speak in my best 'old west' voice for fun)
around these parts, we like things mighty technical! full model numbers and serial numbers are great. if you don't like ta post'in the full serial number, at least give us the manufacturing date of the unit as that is what we are interested in...you may not think it matters, but it does, see-uns how designs change over the years.
another thing is not to post like you know what is good or not gooder. there are a good many people who think they know ever'thing, yet they want us to help-em. you may know a lot...shoot, you may know more than us! but posting things like 'oil pressures look good' don't tell us a darn-fool thing. the more technical information you provide, the faster we kin help ya.
my bestest guess (without any other informa....infoMAT...stuff) is to look at that suction superheat thingy. as them there spinning things go round and round they generates lots o'heat. as they move less of that green 22 goo, they still make bunches of heat but there is less green 22 goo to cool 'em. so oil temps go up.
maybe post a full set o' readin's at full load and at lower loads and stuff and we can get 'er done (spoken well before that chubby guy said it).
good luck...yee haaaaaaa!
(now we return to your regularly scheduled jayguy)
lol. i guess i need to ask better with more info. i will go out and get most recent data and the numbers off of unit. i am always learning. i never went to a school to learn(still learn every day) this trade. i have tried to make the units that i have run by reading and hands on. i need to learn more on what info to give out to get better help from the pro's. i will try to get info in next day or so and post. thanks for any help. technical and other. also i do not type so well. thanks again
hopefully this will give some more info. this is at low load. have not caught it at high load. dont have a lot of original info on unit but maybe this will help.
york model YSDACBS3-CLAS R-22 300 HP think unit is a early 90's model
COND design-480 GPM 85/96 evap design-360 gpm 32/20
26 degree setpoint is what we are running
running conditions at 30% slide valve
suct-18 degree disc-133 degree
sat evap 14 degree cond 83 degree
oil temp 113 oil pressure 136
delta filter 14 lb
cooling water in 67 out 78
glycol in 25 out 22
this is right at low leaving water cutout which is 22 degrees.
dont know if this will help. will try to catch at high load. Thanks
this is why we need all of the information. in your first post, you state the model number is a 'YCAS' and now you say that it is a 'YS'. a YCAS is an air cooled screw chiller with 2 (or more) smaller screw compressors. the YS is a single large screw compressor that is water cooled. this is making more sense now.
how many evaporator passes and how many condenser water passes? your flow rates look very low but it does depend on the number of passes.
you are running about 50F discharge superheat which seems a little high to me, but then again it is glycol, so it probably isn't your greatest problem.
14 psid on your oil filter seems high for something so new and unloaded.
what is the actual oil temperature entering the oil cooler (should be about high 120's if your discharge temperature is 133F) and the actual oil temperature leaving the oil cooler? you could have a faulty 'oil temperature regulator'. what is the refrigerant temperature entering the oil cooler? the leaving refrigerant temperature of the oil cooler?
condenser entering water temperature is pretty low. raising that up will help move more refrigerant. you state tha tthe design is 85F in andd 96F out so you should be ok there...even if you only raised it to 80F.
will get more of the info as i can get back to unit. day or so. the evaporator is a flooded chiller. condensor is a 2 pass. have no control on cooling water temp as it comes off of cooling tower that feeds rest of plant and it ranges from 50 degrees to 90 degrees. not to good to me. using head pressure control valve and is set at 150 lb right now. will get the freon feed temps and oil temps to plate and frame cooler for oil. has been changed to larger cooler. engineer said it was 3 times larger cooler than factory. no regulater to cooler just a solenoid which was changed out and tested for operation. will try to get the loaded compressor numbers as can.i have to catch unit when not in idle i have very little documentation on unit. the flow rates that i gave were what i found for design on that unit. the high oil trip point is 165 degrees thanks
do i need to try to see if i can research number of tubes in each
you don't need the number of tubes. if you are using a head pressure control, then you can raise the pressure pretty easily. also, the oil temperature regulator that i mentioned was actually a reference to the txv that is controlling the refrigerant.
Originally Posted by guess1956
there is no txv on system. only metering device is an orifice between condensor and evaporator for freon.. the only thing that controls oil is the solenoid on the oil feed to cooler and that is working as it was replaced with new just because. and did check for operation because have seen new stuff not work.i hope this is what you are refering to. this is a fairly basic system as controls go.
thanks for being patient.