CVHE320 PURGE UNIT urgent

[mr hottstepper]

sorry 96 entering the cooling tower, which would be 96dgf leaving the condenser , sorry abt that

[mr hottstepper]

I was just verifying because you said your ENTERING water was 96*.

Verify your water flow.

If that is good then check condenser approach.

Compare actual liquid temp to condenser pressure converted to temp. If there is a difference of more than 1-2 degrees then you may have air in the chiller. The wider the difference the more air you may have.

If you have air now check out the purge unit.

Troubleshooting the purge deserves a whole thread of it's own.

k thanks alot really appreciate all the help . i didnt think about checking that but my guess is still the purge unit but. why could it have so much air and purge unit not come on ? or maybe there is water in the purge sump? hmmm

[triggerhappy]

k thanks alot really appreciate all the help . i didnt think about checking that but my guess is still the purge unit but. why could it have so much air and purge unit not come on ? or maybe there is water in the purge sump? hmmm

You may be missing the point here.

You need to determine if the machine has air in it first.

If the machine does not have air then your problem is not with the purge.

If the machine does have air and the purge is not pumping out then you need to determine what is wrong with the purge.

Loss of charge, bad compressor(will not pump),restriction or bad txv are the most likely if the compressor is in fact running on the purge unit.

Like I said earlier just valve off the purge unit and it will pump out if the purge is working. You can even introduce some air into the valved off purge to determine if it is working.

This thread has gotten alot more complicated than it really is.

[mr hottstepper]

You may be missing the point here.

You need to determine if the machine has air in it first.

If the machine does not have air then your problem is not with the purge.

If the machine does have air and the purge is not pumping out then you need to determine what is wrong with the purge.

Loss of charge, bad compressor(will not pump),restriction or bad txv are the most likely if the compressor is in fact running on the purge unit.

Like I said earlier just valve off the purge unit and it will pump out if the purge is working. You can even introduce some air into the valved off purge to determine if it is working.

This thread has gotten alot more complicated than it really is.

WILL try what u recommended and let yall know how it goes thanks again for your advice.

[jayguy]

here are the readings,
evap pressure 16hg
cond press-13.5psig
chwe-58degf diff 9degf
chwl-51degf
con-in-96degf
con-out-86degf diff 10degf
current limit setpoint is 81%
water temp set at 50degf...

and trigger is right...this is not that complicated. everybody needs to just slow down. most of the numbers to determine if there is air in the chiller are here.

for R123:
16"Hg = 46F Saturation Temperature
13.5 psig = 117F Saturation Temperature
96F = 4.6 psig Saturation Pressure

ASSUMING a low to very low condenser approach temperature (this can be determined by measuring the ACTUAL chiller liquid line temperature and subtracting the ACTUAL leaving water temperature)...he has about 8 psi of extra head pressure due to air or overcharge....most likely he has air. please verify that the displayed readings are accurate first (including the purge values)...if they are, then use them. if not, don't use them and continue using your measured values.

as for the purge not working, let's assume that the chiller has air in it. the purge compressor and purge fan should be running...if not, investigate and repair. if they are running, then measure the purge compressor suction line (use a bead probe and insulation...i am a HUGE fan of infra-red measuring techniques, but they have their limitations and small, copper lines are a big limitation). if the purge compressor suction temperature READING is the same as what you are MEASURING, then you can bet that it is probably a purge txv or low charge problem. if they do not match, then the purge suction temperature sensor has probably come loose. depending on the purge version, if you are reading an actual temperature on the screen then you have a small thermistor that is screwed into a 'tee' in the purge compressor suction line. the thermistor is NOT sensing the purge refrigerant. the 'tee' is a special fitting that has a small, threaded fitting...refrigerant removal is not required. the thermistor is to be 'baby finger tight' in the tee...more than that and you are going to strip out the thermistor and you will have to buy a new one (or 3 in my case!). do NOT just wire tie it to the side of the suction line...you will be very disappointed.

again, check for air first and when you are done, check it again. working on the purge can suck especially if there isn't any real air in the chiller anyway.

[cperk]

What is the purge operating mode? Is it in adaptive, on or auto? If it's in adaptive or auto it may not run until it's calculated time to purge. For e.g., if the machine has been tight in the past and it only pumped out 5 min. a week then it may have 24 hrs or so, till the purge unit comes on in adaptive mode. My suggestion is to put the purge operating mode to on and see if purge suction starts dropping. If not check purge suction temp. sensor, if O.K. you need to look at all of the things mentioned before. Approach temps. water flows, cond. water entering. Then pull the heads on cond. Question, purge isn't tripped out on max pumpout rate exceeded, is it?

[klove]

Based on the level of working knowledge shown about the equipment in question up to this point, my suggestion would be to get someone that's familiar with the workings of refrigerated purges and low pressure centrifugal chillers to come and help you - it will be well worth the money in saved aggravation and heartache. Of course, that's just my opinion - I could be wrong.........

[servicetrane]

jayguy agree, may be two symptoms: dirty condenser, air in the system (leak)

[Healey Nut]

Based on the level of working knowledge shown about the equipment in question up to this point, my suggestion would be to get someone that's familiar with the workings of refrigerated purges and low pressure centrifugal chillers to come and help you - it will be well worth the money in saved aggravation and heartache. Of course, that's just my opinion - I could be wrong.........

Ditto

[mr hottstepper]

and trigger is right...this is not that complicated. everybody needs to just slow down. most of the numbers to determine if there is air in the chiller are here.

for R123:
16"Hg = 46F Saturation Temperature
13.5 psig = 117F Saturation Temperature
96F = 4.6 psig Saturation Pressure

ASSUMING a low to very low condenser approach temperature (this can be determined by measuring the ACTUAL chiller liquid line temperature and subtracting the ACTUAL leaving water temperature)...he has about 8 psi of extra head pressure due to air or overcharge....most likely he has air. please verify that the displayed readings are accurate first (including the purge values)...if they are, then use them. if not, don't use them and continue using your measured values.

as for the purge not working, let's assume that the chiller has air in it. the purge compressor and purge fan should be running...if not, investigate and repair. if they are running, then measure the purge compressor suction line (use a bead probe and insulation...i am a HUGE fan of infra-red measuring techniques, but they have their limitations and small, copper lines are a big limitation). if the purge compressor suction temperature READING is the same as what you are MEASURING, then you can bet that it is probably a purge txv or low charge problem. if they do not match, then the purge suction temperature sensor has probably come loose. depending on the purge version, if you are reading an actual temperature on the screen then you have a small thermistor that is screwed into a 'tee' in the purge compressor suction line. the thermistor is NOT sensing the purge refrigerant. the 'tee' is a special fitting that has a small, threaded fitting...refrigerant removal is not required. the thermistor is to be 'baby finger tight' in the tee...more than that and you are going to strip out the thermistor and you will have to buy a new one (or 3 in my case!). do NOT just wire tie it to the side of the suction line...you will be very disappointed.

again, check for air first and when you are done, check it again. working on the purge can suck especially if there isn't any real air in the chiller anyway.

NA THAT suction temp probe was the first thing i checked on the purge unit it was reding the same temp as my ir meter, and its insulated the suction line is actually warm to the touch as well( i cable tied the suction sensor on the back up and wrapped it in rubber tex its waokin fine right now) yes the purge compressor and fan are workin the air is kinda warm comin out of condenser fan the values are correct.

[mr hottstepper]

What is the purge operating mode? Is it in adaptive, on or auto? If it's in adaptive or auto it may not run until it's calculated time to purge. For e.g., if the machine has been tight in the past and it only pumped out 5 min. a week then it may have 24 hrs or so, till the purge unit comes on in adaptive mode. My suggestion is to put the purge operating mode to on and see if purge suction starts dropping. If not check purge suction temp. sensor, if O.K. you need to look at all of the things mentioned before. Approach temps. water flows, cond. water entering. Then pull the heads on cond. Question, purge isn't tripped out on max pumpout rate exceeded, is it?

purge mode was set to on . the baffels on condenser was recently changed , the purge has not tripped on pump out rate i raised it to 99 in 24 and it only did 2 minutes cuz i put it on manually. their water guages spoilt , but the back up chiller of same make and tonnage when started runs perfect so i doubt the flow rate is off ill in stall 2 guages wen i return there thr or friday,the condenser tubes were also cleaned

[mr hottstepper]

Based on the level of working knowledge shown about the equipment in question up to this point, my suggestion would be to get someone that's familiar with the workings of refrigerated purges and low pressure centrifugal chillers to come and help you - it will be well worth the money in saved aggravation and heartache. Of course, that's just my opinion - I could be wrong.........

as far as getting someone else to come check it lets put it like this there are probaly about 6 people in my country that works on chillers 2 that work on trane systems and low pressure centrifugal systems the other people who currently holds the contract asked(begged) me to take over and fix it for them , besides most of the centrifugal problems are electronic which is to easy to repair, ... but i have anaylized thge system and was just askin for a little insight on what could be wrong from people with more experience in this PARTICULAR type of low pressure system , so the only other people to call are u gyus . after all thats the porpuse of this forum to ask for a lil help - then again i could be wrong.................

[deltap10]

Purifier or Earthwise? What control panel? I rarely see a HP trip because the surging is so bad before that someone shuts the machine down or it goes down on extended surge. Get someone to help you with this one. Read the purge literature. Isolate the purge and do refrigeration temp.checks. Add some air to the purge chamber. You should see the suction temp. drop rapidly. Check the pumpout orofice for dirt. Manually energize pumpout comp. Does it pull 28" vacuum? Do solenoids energize and open? Can you see R123 cycling through sight glass? Install bypass hose or remove orofice until air is out. Leak check chiller. Repair leaks.

[klove]

as far as getting someone else to come check it lets put it like this there are probaly about 6 people in my country that works on chillers 2 that work on trane systems and low pressure centrifugal systems the other people who currently holds the contract asked(begged) me to take over and fix it for them , besides most of the centrifugal problems are electronic which is to easy to repair, ... but i have anaylized thge system and was just askin for a little insight on what could be wrong from people with more experience in this PARTICULAR type of low pressure system , so the only other people to call are u gyus . after all thats the porpuse of this forum to ask for a lil help - then again i could be wrong.................

No idea what country you're in. I looked at your location and it says "tt, wi". I thought you were in Tubert Town, Wisconsin. I also read your biography. I must say that there's a lot of intrinsic praise in there. Based on that, I'll stick with my first post as my best suggestion.

[mr hottstepper]

Purifier or Earthwise? What control panel? I rarely see a HP trip because the surging is so bad before that someone shuts the machine down or it goes down on extended surge. Get someone to help you with this one. Read the purge literature. Isolate the purge and do refrigeration temp.checks. Add some air to the purge chamber. You should see the suction temp. drop rapidly. Check the pumpout orofice for dirt. Manually energize pumpout comp. Does it pull 28" vacuum? Do solenoids energize and open? Can you see R123 cycling through sight glass? Install bypass hose or remove orofice until air is out. Leak check chiller. Repair leaks.

purifer, ucp1, no surge machine jus runs to 16psig and cuts on hi press cutout

[mr hottstepper]

No idea what country you're in. I looked at your location and it says "tt, wi". I thought you were in Tubert Town, Wisconsin. I also read your biography. I must say that there's a lot of intrinsic praise in there. Based on that, I'll stick with my first post as my best suggestion.

im not tryin to argue or make enimies,or waste time im a contractor trying to make money and learn cuz i really love thermodynamics, just like u , and i think i have a valid question and a problem thats worth bringing forward and i have tried most of what was recommended by other members before so i dont think im that bad off.im from the caribbean btw , i tend to get a little beside myself sometimes , . dude i jus wanna get the equipment running ,i just asked for a lil help im sure when u started to work on these equipment you didnt know everything, but i welcome a challange cuz this isnt really a js compressor or screw,or gas fired absorb system,or one of those tecogen natural gas engine driven chillers, it is a piece of work and i really wanna see this job tru, ....and if u guys think thats something they want me to overhaul the backup cvhe chiller from pre rotational veins the works befor the year ends , the bearings in the motor are singing away, i alreddy signed up to go la croose for cvhe mechanical but they said i have to do cvhe fundementals first,but cuz of my good business with them they will try get me in the mechanical on nov 1st but i cant leave the equipment hanging till then, so im here jus tryin get some advice frm u guys, beside how would u like it if u went to get a light bulb in the supermarket and they told you they only sell light bulbs to electricans. u doh hav to gimme such a hard time because i dont no more about low pressure centrifugal than you.

[deltap10]

If the condenser has a marine water box,open that end and check the divider plate. I've had to weld new channels in many of them.

[mr hottstepper]

If the condenser has a marine water box,open that end and check the divider plate. I've had to weld new channels in many of them.

NOPE theres no exchanger on the condenser frame actually looked to see if it had one cause i had to do the same with a carrier XRV centrifugal last year but it was 134a not vaccum. i even inspected the rapture guard ,cuz that has a way of spoiling a good day.

[Trane_Dude]

Haven't read this entire thread, but it is not uncommon after 30-80K hours for the compressor valves to fail on the condensing unit. When the valves fail or partially fail the unit simply will not do its job. Check the discharge line when it's running. It should be quite hot to the touch, if it isn't then order a new condensing unit (complete) new expansion valve and copper-spun dryer.

[klove]

im not tryin to argue or make enimies,or waste time im a contractor trying to make money and learn cuz i really love thermodynamics, just like u , and i think i have a valid question and a problem thats worth bringing forward and i have tried most of what was recommended by other members before so i dont think im that bad off.im from the caribbean btw , i tend to get a little beside myself sometimes , . dude i jus wanna get the equipment running ,i just asked for a lil help im sure when u started to work on these equipment you didnt know everything, but i welcome a challange cuz this isnt really a js compressor or screw,or gas fired absorb system,or one of those tecogen natural gas engine driven chillers, it is a piece of work and i really wanna see this job tru, ....and if u guys think thats something they want me to overhaul the backup cvhe chiller from pre rotational veins the works befor the year ends , the bearings in the motor are singing away, i alreddy signed up to go la croose for cvhe mechanical but they said i have to do cvhe fundementals first,but cuz of my good business with them they will try get me in the mechanical on nov 1st but i cant leave the equipment hanging till then, so im here jus tryin get some advice frm u guys, beside how would u like it if u went to get a light bulb in the supermarket and they told you they only sell light bulbs to electricans. u doh hav to gimme such a hard time because i dont no more about low pressure centrifugal than you.

No offense intended. I wish you the best of luck in figuring out where your problem lies.