Trane Chiller RTAD 115

[meab]

Hi All,

Trane Chiller RTAD 115 has 2 No. Helrotor Compressors,
Active Chilled Water Setpoint= 6 Deg C
Evap entering Water Temp = 15.3 Deg C
Evap Leaving Water Temp = 12.5 Deg C
Active Current Limit Setpoint = 120%
Chiller % RLA =69%
Outdoor Air Temp = 31Deg C
CKT 1 Evap Refrigerant Pressure = 359.8kPa
CKT 1 Cond Refrigerant Pressure = 1085.3 kPa
CKT 1 Comp Suction Refrigerant Temp = 26.3 Deg C
CKT 1 Saturated Evap Refrigerant = 13 Deg C
CKT 1 Saturated Cond Refrigerant Temp 45.6 Deg C

CKT 2 Evap Refrigerant Pressure = 293.8 kPa
CKT 2 Cond Refrigerant Pressure = 996.2 kPa
CKT 2 Comp Suction Refrigerant Temp = 11.6 Deg C
CKT 2 Saturated Evap Refrigerant = 7.7 Deg C
CKT 2 Saturated Cond Refrigerant Temp 42.5 Deg C

I Suspect Lack of refrigerant that is why unit running only at 69% any other Suggestions very much appreciated.

Thanks

[CV_Geardrive]

Hello Meab,
Please let us know %RLA per compressor and unit / compressor status. (Unit is running, Evaporator limit, Condenser limit, Current limit)
Also check if the actual temperature of suction line on CKT1 is 26°C. I suspect damaged sensor. (Sat temp > water outlet, reverse (negative) approach)
Maybe the water temperature is dropping too fast and the unit is not further loading.
Please check if female loaders are loaded on each compressor.
Regards,
CV

[meab]

CV Geardrive

Thanks for your response. the compressors running at 67 and 70 %

Thanks

[meab]

CV Geardrive

sorry also the female loaders are not loaded on both compressors.

Thanks

[CV_Geardrive]

Meab,
If the female loaders are not loaded you can’t have further loading by slide valve.
Usually the unit starts one compressor and after 2 minutes energizes the female and then begins load-unload sequence by slide valve movement with load – unload valves.
It is strange that you have both compressors in operation and both females not energized. This can happen only in unloading while the outlet temperature is on or bellow set point or when the unit was in set point and suddenly great thermal loads came in. Both situations are not last more than 2 to 5 minutes.
So you have to check the status of each compressor and the unit status to see if you have any limitation. (Unit is running, Evaporator limit, Condenser limit, Current limit)
If you don’t have any limitation measure in reference to neutral or ground the output of each compressor module (A20-1, A20-2) on points J7 9. You should find 115VAC.
If you have 115VAC and the females are not loaded (energized) then you have problem with both coils or you have wire / connection problem.
If after of, at least, 2 minutes of operation you don’t have 115VAC then you may have problem with both boards or you have to check the programming of controller.
Maybe you have configuration for wrong type of compressor.
Please rename file extensions to .rar
Regards,
CV

[goshen]

Hi All,

Trane Chiller RTAD 115 has 2 No. Helrotor Compressors,
Active Chilled Water Setpoint= 6 Deg C
Evap entering Water Temp = 15.3 Deg C
Evap Leaving Water Temp = 12.5 Deg C
Active Current Limit Setpoint = 120%
Chiller % RLA =69%
Outdoor Air Temp = 31Deg C
CKT 1 Evap Refrigerant Pressure = 359.8kPa
CKT 1 Cond Refrigerant Pressure = 1085.3 kPa
CKT 1 Comp Suction Refrigerant Temp = 26.3 Deg C
CKT 1 Saturated Evap Refrigerant = 13 Deg C
CKT 1 Saturated Cond Refrigerant Temp 45.6 Deg C

CKT 2 Evap Refrigerant Pressure = 293.8 kPa
CKT 2 Cond Refrigerant Pressure = 996.2 kPa
CKT 2 Comp Suction Refrigerant Temp = 11.6 Deg C
CKT 2 Saturated Evap Refrigerant = 7.7 Deg C
CKT 2 Saturated Cond Refrigerant Temp 42.5 Deg C

I Suspect Lack of refrigerant that is why unit running only at 69% any other Suggestions very much appreciated.

Thanks
Hi
it would seem that you are using R134a in this unit.
your delta t is approx 7 degc that is far from the design delta.
your water temp is relativly high and folowing is your head pressure.
i think your unit is unloading due to the high pressure!
you should check that this units tonnage is sufficent for your sys!
also what is your water pressure drop?
if you have more than 0.5 bar this can also explain your problem.
as for ckt1 your suction temp is high check it with an external probe it might be faulty.
you should also check subcooling this will give you an exact status if you are lacking any refrigerant.
good luck

[meab]

Thanks to you guys for your advise will get back to you.

CV Geardrive am not able to open the files you have posted even after renaming to .rar can you please email to me on following address dtrekmsa@yahoo.com

Thanks

[CV_Geardrive]

Hi,
Please check your email.
PLEASE let me know if the unit has a limiting status.
Regards,
CV

[CV_Geardrive]

Hi again,
Except that you have to check your email, please ignore rest.
The unit has too high sat evaporator temperature / pressure to have evaporator limit.
The unit has too low sat condenser temperature / pressure to have condenser limit.
The unit has too low current % to have current limit.
Check above in reference to the files I sent you.
I suppose that the unit status is just “RUNNING”
Regards,
CV

[meab]

Hi CV Geardrive

Thanks have received the files you mailed to me let me go thru them and compare to settings on unit and will get back to you

[meab]

HI Goshen/ CV Geardrive

You are right the unit is using R134a. water pressure drop about plays between 0.2 and 0.3 bar

Checked the unit

female solenoid (2Y23) loads after about 2 mins from start up
Comp unload solenoid valve (2Y21) energises for a second and stays off for about 12 secs
comp load solenoid valve (2Y22) continous on from start up

Active current setpoint is 120%
Chilled water reset type - Return water
Return water reset ratio - 50%
Checked oil level in ckt B @ 110 mm in the receiver
oil level in ckt A @ 450 mm in receiver

Secondly the unit Ckt B makes a loud rattling noise and was locked out due to this maybe due to oil a little less. (110mm) the rattling noise starts about 30 mins of running not immediately on start up.

[CV_Geardrive]

Hi Meab,
In “OPERATOR SETTINGS” set the “EXTERNAL CHILLED WATER SET POINT” to “DISABLE”.
Also in same menu set the “CHILLED WATER RESET TYPE” to “NONE”.
SOLENOIDS:
When you start the unit the control energizes the unload solenoid and start counting 120 seconds. See “SERVICE SETTINGS” à “Restart inhibit time”.
About 20 seconds before 0 control is positioning the EXV. (EXV pre-position interval)
At 0 time starts the compressor at 30% of refrigerant capacity and for the next 120 seconds keeps the unload solenoid energized.
At 120 seconds of operation de-energizes the unload solenoid and increase the refrigerant capacity to 60% by energizing the female solenoid.
After more or less 10 seconds starts to modulate capacity by movement of slide valve with load and unload solenoids.
Please check this sequence in reference to attachment and act accordingly.
OIL:
45cm oil level is too much.
11cm oil level is lower than normal but it is not bad.
A normal value is 15 to 20 cm.
NOISE:
After you fix the unit and operates according to “SOLENOIDS” section, check the oil temperature in reference to saturated condenser temperature.
If after 30 minutes of operation the oil temperature should not be lower than 8°C in reference to saturated condenser temperature.
If it is bellow or about 8°C then you can do the following. (Easier to harder)
1. Clean the condenser.
2. Add a small quantity of oil.
3. Change the oil filter.
4. Change the oil check valve. It is located after the oil filter inside compressor.
Regards,
CV

[meab]

Hi CV Geardrive

Thanks for the above will get back to you

Cheers

[meab]

Hi CV Geardrive

Yesterday was at the site Checked and found the EXTERNAL CHILLED WATER SET POINT was on Disable and CHILLED WATER RESET TYPE was on return water set to Disable.
Then tried to follow the sequence of the Solenoids and found that the Male unload solenoid was energised throught out from the word GO even in stop mode it is still energised this is for both the Circuit 1 and 2.
Could the problem be the Modules but then again both Modules are behaving the same.

Please advise

Thanks.

[CV_Geardrive]

Hi Meab,
If you don’t have limiting operation, most probably you have problem in wiring of load/unload coils.
Please check wiring.
If you remove wires from modules you may have always 110VAC because these outputs are not relays but triacs.
If you want to separate coils from module (for testing) you can install two pilot relays to module outputs.
The possibility of both modules failure is very low.
Please let us know the age of the unit and when the problem occurred.
Removing coil from valve when energized will cause coil failure.
Regards,
CV

[meab]

Hi CV Geardrive

would like to request if you do have wiring diagram for this unit please mail to me so i can try and follow up on the wiring.
As to when the problem started can not tell as client says the unit has not been performing good for about an year

Thanks

[CV_Geardrive]

Hi,
Check your email.
CV

[meab]

Hi CV

Thanks for the wiring diagram.

Checked on the wiring all is OK. checked all the settings seems fine. But the unload solenoid still stays energised through out tried to modulate to modulate the solenoid valve manually by removing and replacing the solenoid coil for about 10 seconds and the compressor capacity increased to 103% from 70% infact even the compressor sound changes the rattling sound reduced so much, Wonder what the problem could be??? dont think it is the module

[CV_Geardrive]

Hi Meab,
The answer to your problem is what repairs and by who have been done and what parts have been used before 3 years.
If for example you find out that coils have been replaced!! then you probably know that old coils burn out (by mistake!) and took together the triacs.
Also:
Both coils are getting command by A20-1 or 2 module in points E7 & E8.
These two wires (HOT X2-1) are going to coils via two connection points. One in the control panel and the other to compressor junction box.
After these points wires are going to coils. The other two wires (NEUTRAL) are connected together with neutral of female loader and go to neutral of junction box point. Then one wire (NEUTRAL) is going to general neutral of unit X2-2.
Please check the integrity of this circuit in both compressors.
If wiring is OK and you have made all previous checks of all posts and the unit have no limiting status then you may have two choices.
1. Remove a compressor module ask for triac check out by electronic specialist. (Replacing of triac is very easy)
2. Order one new compressor module. (Use TRANE part number MOD01200, check with local office or dealer)
At your disposal.
Regards,
CV

[meab]

Hi CV

Yes it looks like 2 of the solenoid coils were replaced, as they did not have the part No. Stickers :- e.g 2Y21-1 and 2Y22-2 and looked newer then the others.

Thanks again for all your advise will get back to you

Regards
Meab

[imran ansari]

Hi CV Geardrive

Thanks for the above will get back to you

Cheers
set chilled water setpoint from return water to disabled

[imran ansari]

nothing wrong with female loading valve just check. set you water setpoint to retrun water to diabled from service setting

[meab]

Hi Guys

Thanks CV Geardrive and Goshen for the advise.

Yesterday Managed to replace the 2 compressor modules and also replaced ckt 1 entering evaporator refrigerant temp sensor, and the chiller performance has improved very much leaving water temp now at about 7.4 degrees Centigrade. Compressors running at A 97% and B 114%.thinking of topping up refrigerant in system one.
Now if anybody has a replacement parts list for the above chiller unit as client would like to order for some parts and keep on standby i will appreciate if can get one.

Thanks again for the advise

[meab]

Hi Imran Ansari

The return water has been set to Disabled

Thanks

[meab]

Hi Imran Ansari

Yes the Chilled water setpoint has been set to Disabled

Thanks

[CV_Geardrive]

Hi Meab,
Send me a log at the above running conditions in order to tell you my opinion about refrigerant charge.
Also send me:
Unit full model number. (ERTAD115XXXXXXXXXXXXXXXXXXXXXXXXXX……)
Unit serial number.
Unit order number.
Compressors full model number. (You can find them in compressors bodies. CHHPXXXXXXXXX…….)
Most probably there is a white sticker in the inside of panel doors.
In this sticker you can see full model number and order number.
With these data I can send you full parts list for unit and compressors.
Send them in my email.
Regards,
CV

[meab]

Hi. CV

Please check your mail

Regards
meab

[CV_Geardrive]

Hi Meab,
Pls check your email
Regards,
CV

[meab]

Hi. CV Geardrive

Thanks received the mails and appriciate all the assistance you have given me.
will check on phase unbalance and get back to you

thanks and best regards

meab

[Whitney]

Good Morning,
. Currently I am trying to get a Trane RTAA 400 (400 ton chiller) up and running for the new season some fuses were blown, troubleshot and replaced fan motors and completed all other PM ie cleaned coils checked levels etc, now am having a Evaporator Refrigerant Temp Sensor error on ckt 2. (error 94). My question is whether or not this repair requires a circuit isolation and an un-charge of the line or can this sensor be changed on the fly like a car where it simply is unscrewed and replaced ? This is a chilled water/glycol system fyi
Thank You in advance
W

[mugris]

Can you send me th wiring diagrams?? I have a RTAD 100

[mugris]

please send to mugris3@hotmail.com

[chillerman2006]

Can you send me th wiring diagrams?? I have a RTAD 100

bribe me & I'll:rolleyes:

Deal ?

[install monkey]

normally theres a wiring diagram inside the control circuit door!!

[chillerman2006]

normally theres a wiring diagram inside the control circuit door!!

damn! thats blown it - was hoping he went for second option:D

[install monkey]

damn! thats blown it - was hoping he went for second option:D

his mrs might be bigger than mine! i need to do a method and risk assesment if i want to have a do! coz she wears the trousers -custom made 48waist and 28leg! id prefer her 28waist and 48 leg! but its amazing once they get a ring on there finger they start liking cake!!!haha

[chillerman2006]

his mrs might be bigger than mine! i need to do a method and risk assesment if i want to have a do! coz she wears the trousers -custom made 48waist and 28leg! id prefer her 28waist and 48 leg! but its amazing once they get a ring on there finger they start liking cake!!!haha

Just as I read this mine waddled over & put her pile of sweet wrappers in the bin saying 'wat you laughing at' :D:D:D

[install monkey]

check the wrappers! theyre firemans favourites! haha:p

[chillerman2006]

check the wrappers! theyre firemans favourites! haha:p

yeah ! probaly or mr bartlett's
:D