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giovanni
11-05-2006, 08:18 AM
Hello everyone I am new to this site and the field in general. What I have learned has come from service techs and reading various mags, manuals,and tons of knowledge from this site. I work at an ice rink and we will be purchasing a new complete package. WE currently have a carrier 30gt 200 tons (***** and gylcol system) for the past 9 years. We recently had to have a rental unit set up because only 5 of the 7 comperssors are working. They are reciprocating compessors and have had a lot of service and have seen better days and maintainence costs have out weighed anymore repairs.
Can anyone advise on using reciprocating or screw compressors. I have heard that reciprocating require a lot of maintainence but are cheaper in price as opposed to screw which are more expensive but are more reliable and have less maintainence costs. Any advice would greatly appreciated. Thank you.

NoNickName
11-05-2006, 12:41 PM
We have been using screws for some time, and I can't say they are more reliable. 40.000 hours is the average MTB overhauls for bearings.
Of course there are exceptions: some manufacturers have good and reliable screw cmps, others suck.
For 200 tons I would still suggest semi recips or a small one or two circuits screw cmps chiller with bitzers.

US Iceman
11-05-2006, 02:30 PM
Hi giovanni,

The chiller you currently have is an air conditioning chiller that is derated for use with glycol. If it is only 9 years old and being replaced already it has been badly treated.


They are reciprocating compressors and have had a lot of service and have seen better days and maintenance costs have out weighed anymore repairs.


The compressor type has nothing to go with the problem. I suspect the chiller has not been serviced properly with very low regular maintenance performed. Any system should last longer than this.


I have heard that reciprocating require a lot of maintenance but are cheaper in price as opposed to screw which are more expensive but are more reliable and have less maintenance costs.

Not necessarily true. Almost all of the compressors can be reliable if they are serviced and installed correctly.

How is the system started? Is it simply turned on and allowed to run all of the compressors at full capacity until the floor is frozen? Most of the rinks I've seen operate like this and it contributes to the most repairs and energy use.

Most of the ice rink chillers I have seen use industrial open drive reciprocating compressors.

The MG Pony
11-05-2006, 06:03 PM
I'm with US 9years is way too short lived for any real system, some one was very mean to it.

old gas bottle
11-05-2006, 06:51 PM
i think some of the build quality of newer chiller packs is poor to say the least,condensers failing,gas leaks from cheap pipework,then leading to compressor failures and so on,yes good maintainence is very important but price is the catalist,back to the ice rink,have a look at the J&E HALL website,good solid units.

US Iceman
11-05-2006, 07:27 PM
giovanni,

Here is a contact for someone very close to you. They are down in Johnstown, PA.

http://www.burleys.com/

I would recommend you at least talk to them for other ideas and considerations.

Josip
12-05-2006, 10:35 PM
Hi, giovanni :)


WE currently have a carrier 30gt 200 tons (***** and gylcol system)


We have been using screws for some time, and I can't say they are more reliable. 40.000 hours is the average MTB overhauls for bearings.
Of course there are exceptions: some manufacturers have good and reliable screw cmps, others suck.
For 200 tons I would still suggest semi recips or a small one or two circuits screw cmps chiller with bitzers.


Most of the ice rink chillers I have seen use industrial open drive reciprocating compressors.


yes good maintainence is very important but price is the catalist

You must be very :confused:

How many suggestions :eek: , and all of them different, mine too ;)

I'll try to suggest something also but final decision must be done by you :D

For 200 tons (700kW) you can use 2 x Turbocor by 90 tons :)

http://www.turbocor.com

Or you can see about ammonia open screw or piston with PHE for glycol with very small amount of ammonia. Of course with VFD (variable frequency drive or rotatune)

http://www.sabroe.com/Products/Standard%20package%20solutions/PAC%20chillers%20-%20screw%20/index.html

Today you have a lot of screw compressors with roller bearings and without full time running oil pump, that means all of them are reliable for long time, of course with proper maintenance.

It is not easy to decide what to install.

Come back with decision

Best regrds,

Josip :)

Renato RR
13-05-2006, 09:45 AM
Some points:
1)Carrier
2)9 years
3)frequently repairs

Answer:
Find service crew with good reputation and analise sitem performance.If is posible get all bils for maintance in past 9 years and se what they did on the machine.
First report then analise old system.
Old generation of Carrier chiller is goooood goood machine.
Problem is in the construction not in the chiller.

Renato

giovanni
26-05-2006, 06:53 AM
Guys sorry for the delay in responding I was unable to log in, technical difficulites I guess. First Thanks for the responses. We finally laid the 30GT to rest and currently renting a 200 ton chiller from carrier. Its actually a Trane unit. They bought out some small division from them. It is a model RTAA200. 2 screw compressors and doing the job fantastically. WE are going to see how it holds up in the summer and see if it gives us good ice. With the old unit the ice was wet in the summer in a lot of spots.

You guys hit the nail right on the head with service. I checked the old records from before I worked there and the only time service techs showed up was when there was a problem. They had an independant service company. Tried to save money. guess you have all heard that before.. No maintenance on the unit other than a cleaning once a year and the cleaner they used ate up the fins,,, I later learned just to use water once a week to keep the condensor fins clean. There was hardly no air flow at all before. I got the air flowing thru the fins but it was a little to late. The unit was working so hard that they replaced 5 compressors in 2 years. When the tech asked me why I reading the manual I knew we were in trouble.... Thanks again for all the help and I sort of answered my own questions a bit.

RIF... reading is fundamental LOL

bruceboldy
26-05-2006, 11:17 PM
Glad to hear our chiller is doing well. that RTAA PACKAGE IS VERY COMPETITIVE in price and is easy to service
let me know if you need some info or literature on it
I sell a lot of those units.
Also check with Mollenberg Betz in Buffalo they are experts in ice rinks.

Bruce

Texas Trane

giovanni
27-05-2006, 09:20 AM
so far we are happy with the unit (RTAA). We are using it as a rental. The real test will be this weekend when the temperatures should be in the mid 80's here in NY. As the temps got higher we were getting wet spots on the ice which was probably due to the older chiller's poor lack of maintenance and service. we just had the set point lowered to +12 from +15 degrees and it has made a difference so far. Thanks for the reply and offer

giovanni
28-05-2006, 05:12 AM
sorry about delay in response thanks for the info we are renting a trane rtaa200 for the time being

giovanni
28-05-2006, 05:16 AM
Brunce can I ask where I may download or obtain an users manual for the trane rtaa200. and also the model we have has the ability to lower the set point as low as zero. any opinions on that. We are currently at +12 degrees and we had dome damp spots on the ice today

Samarjit Sen
28-05-2006, 03:47 PM
Hi Giovanni,
With the capacity rating as suggested by you, I would suggest that you may contact J&E Hall for their Screw Compressors or Dorin, Italy for their Semi Hermetic Compressor Racks.

Samarjit Sen

giovanni
29-05-2006, 06:28 AM
Thanks Samartij but I think the owner and manager might stay with Carrier if this rental works out Carrier proposed a 240 ton unit with screws. There are a lot of variables in the decision which I should have mentioned earlier. This is not a regular building it is a bubble dome and the problem with that is cooing the bldg which the ice itself does for the mostpart. We do have dehumidiers and and air conditioning but a bubble is a problem in itself

zvikard
01-07-2006, 01:06 PM
Hi everybody , i'm new in this forum , and i have a question , what is the meaning of the numbers engraved on the face of the screw shaft in the Trane screw compressors , model CHHB100 ? , both screws have the exact same number engraved ,(only 3 digits) .
I will apreciate the info , thanks , Tzvi.

chemi-cool
02-07-2006, 07:18 PM
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