Need some help:(

[okan]

We have Trane RTHD in our plant which is installed 2 months ago.We are having oil loss at compressor problem.We are using directly river water in condenser and we have a variable cooling need conditions.The river water temperature is 11-13 C in this winter.Altough head pressure,oil pressure,refrigerant luquid level is OK we sometimes face oil loss problem.

Evap entering water 1.2C
Evap leaving temp -2.8C
Condenser entering water 12C
Condenser leaving water 13C

Evap refrigerant pressure 136
Condenser ref. pressure 400

Evap app. temp : 3-4 C
Condenser app. temp: 1-2C
Load: %42

Chiller works in above conditions about 75-80 minutes.Then as we dont have cooling need so much it goes to;
Evap entering water -1.7C
Evap leaving temp -3C
Condenser entering water 12C
Condenser leaving water 12.5C

Evap refrigerant pressure 128
Condenser ref. pressure 360

Evap app. temp : 2 C
Condenser app. temp: 0.8C
Load: %26

But after working 6-7 hours while in above conditions the chiller goes to "oil loss"
İs this because of cold condenser water?If I can warm it up to 20 C then is everthing going to be OK?

Many thanks for asnwers

[Pat A/C]

This runs on what refrigerant and when u say it runs at 400 is that psi,and yes condenser water is to cold

[Pat A/C]

You must have the design sheet of the chiller ,that will tell you what should be the entering and leaving temp for the evap and cond and the gpm

[spinning wheel]

WARRANTY!!!!!!!! Call Trane.

[Healey Nut]

No condenser water temp control , no water treatment ..........Kiss the Warranty goodbye ...its in great big print in the IOM and on labels on the chiller .

[okan]

We have a condenser regulating valve in the outlet of condenser and works when the head pressure is under limits(1,7 bar).The data sheet says;

Evap. entering temp 2 C
Evap leaving temp -3 C

Condenser ent. temp 25 C
Condenser leaving temp 30 C

But it also says you can use cold water minimum 12.5C and as far as I know cold water means lower power suction.

[Healey Nut]

Read the rules at the top of the page .....NO DIY ......... CALL A PRO

[Tech Rob]

Read the rules at the top of the page .....NO DIY ......... CALL A PRO

Who said anything about DIY? If the machine is only two months old, I agree that the owner should have Trane come out and look at the thing.

[R123]

Why don't you convert all the temps to F and pressures to PSI for the metrically challenged.

[Pat A/C]

Okan convert pressures and temps to psi and degree F like R123 said ,and explain more ur operation of the valve at the outlet of ur condenser and I still say water in at the condenser is to cold bring that up to 25 c

[spinning wheel]

This is the problem with us in America. The entire word uses metric units, we even signed an agreement to start converting to it. However, we are cowboys and refuse to learn new ways. So to the rest of the world, if you want an Americans help, convert to imperial units please. We are to lazy to learn it!
Thank You, for understanding our limitations.

[Screwit]

Is the chiller controlling the cond water reg valve or is this external control, the chiller does not need to be controlled to have 25 Deg C ECWT provided the refrigerant differential pressure is being made. The chiller can control this directly by throttling the CLWT. I also agree with Graham, Healay Nut - if your running direct river water for the condenser you are going to run into serious issues sooner than later with the heat exchanger. Not sure why this is a product warranty issue, sounds like installation issues to me on information available

[spinning wheel]

I am sure that a Trane service person started the chiller and performed a commisioning report. During this time the start up tech should have explained the unit's limitations if any and configured the condenser water flow valve, if it was supplied by the Trane branch. Anyone who works on ships or chemical plants by a water source will have experienced this before. Not the end of the world, just some problems to contend with. This is a Trane problem as the sales guy sold them this chiller and they knew where it was going. The only problem is who pays for it "Trane warranty department or the sale department."

[jayguy]

I am sure that a Trane service person started the chiller and performed a commisioning report....This is a Trane problem as the sales guy sold them this chiller and they knew where it was going...."

not necessarily. i have run into many jobs where i spoke with the salesman and he did not know where it was going or what it is going to do. often times (when they are lucky) they get a decent set of conditions. when they aren't, they get a set of conditions like: 75 tons of cooling, no heat, economizer...need it in 4 weeks.

that is the truth...it may be wrong to do it that way...but this is how it is done many times. as for a Trane service tech doing the start up...doesn't always happen and it is not required by trane for this model in order to get the warranty.

[okan]

I would like to thank everyone for help.A trane tech started up the unit and told the limits.He just adviced to warm the water but said there should be no problem with this condenser water.They installad an electronic card which controls the regulating valve but it only works when system differantial pressure is under the limits otherwise it is full open.We have been using direct river water since years fot the oher chillers and also heat exchanger and had no problem so far as we have a good filtration.

I already called the Trane tech.When start up he did not say you should warm the water but now says you should warm the water.When I ask him that all the conditions are ok,gas pump working-system differantial pressure is not under limits-the check valve is ok(We hope so because the machine is new) what the reason is for oil loss problem I could not receive a good answer he just said warm the water and if you still have this problem we will come again and check the other things.But I dont want to spend money for it before I am sure that the problem is cold condenser water.

Thanks to everyone who wants to help and also special thanks to PAT A/C friend.I will convert the units tomorrow and write here

[Screwit]

Your entering condenser water is below minimum (refer to the bulletin on CW control posted in the previous post) but you also have an issue with your flows as you have 4K delta on youe evap (design 5K) and only 1K delta on your condenser (design 5 K). I suspect you are way down on evap flow by your percentage RLA of 42% and no that ain't equipment waranty.

Actual
Evap entering water 1.2C
Evap leaving temp -2.8C
Condenser entering water 12C
Condenser leaving water 13C

Design
Evap. entering temp 2 C
Evap leaving temp -3 C
Condenser ent. temp 25 C
Condenser leaving temp 30 C

[Screwit]

And converted for the metrically challenged......

We have Trane RTHD in our plant which is installed 2 months ago. We are having oil loss at compressor problem. We are using directly river water in condenser and we have a variable cooling need conditions. The river water temperature is 11-13 C (52-55.4 F) in this winter. Although head pressure,oil pressure,refrigerant luquid level is OK we sometimes face oil loss problem

Evap entering water 1.2C (34.2 F)
Evap leaving temp -2.8C (27 F)
Condenser entering water 12C (53.6 F)
Condenser leaving water 13C (55.4 F)

Evap refrigerant pressure 136 (20 psig)
Condenser ref. pressure 400 (58 psig)

Evap app. temp : 3-4 C (3.2 to 7.2 F)
Condenser app. temp: 1-2C (1.8 to 3.6 F)
Load: %42

Chiller works in above conditions about 75-80 minutes.Then as we dont have cooling need so much it goes to;
Evap entering water -1.7C (29 F)
Evap leaving temp -3C (26.6 F)
Condenser entering water 12C (53.6 F)
Condenser leaving water 12.5C (54.5 F)

Evap refrigerant pressure 128 (18.5 psig)
Condenser ref. pressure 360 (52 psig)

Evap app. temp : 2 C (3.6 F)
Condenser app. temp: 0.8C (1.4 F)
Load: %26

We have a condenser regulating valve in the outlet of condenser and works when the head pressure is under limits(1,7 bar 24 psid)).The data sheet says;

Evap. entering temp 2 C (35.6 F)
Evap leaving temp -3 C (26.6 F)

Condenser ent. temp 25 C (77 F)
Condenser leaving temp 30 C (86 F)

But it also says you can use cold water minimum 12.5C (54.5 F) and as far as I know cold water means lower power suction.

[Healey Nut]

Define filtration , A screen with 6" holes in it to remove large fish , dead bodies , skunks, beavers and large fish is a filter and could be described as good filtration....why ...because it works to remove those objects that are too big to pass through it .
When I said water treatment I was meaning chemical treatment to reduce the corrosive qualities and biological nasties , if present in the water being used .

Your condenser water is to cold and just because the "Trane tech" installed the card doesnt mean he set the parameters up properly ??
I have also posted the warning right out of the IOM about untreated water .
This is the page that no one ever reads ...


CAUTION
Proper Water Treatment!
The use of untreated or improperly treated water in a RTHD may
result in scaling, erosion, corrosion, algae or slime. It is
recommended that the services of a qualified water treatment
specialist be engaged to determine what water treatment, if any,
is required. The Trane Company assumes no responsibility for
equipment failures which result from untreated or improperly
treated water, or saline or brackish water.
Using untreated or improperly treated water in these units may result in inefficient
operation and possible tube damage. Consult a qualified water treatment
specialist to determine whether treatment is needed.

[spinning wheel]

That is for a stock unit with copper tubes and steel shells. I would hope that the chiller was ordered for marine conditions CuNi or titanium. This is what usually tips off the sales guy that this is a special chiller. Just because you are using raw water, the manufacturer cannot wash his hands of the chiller unless the customer did not specify thier intentions. Raw water does not cause oil loss; poor operation and maintenance cause oil loss and breakdowns.
Ships don't have cooling towers, I promise you that; and somehow they still work, from the equator to the poles.

[Dallas Duster]

Why don't you convert all the temps to F and pressures to PSI for the metrically challenged.

Just google for a kpa to psi converter .