Issue:
What needs to be done to change unit from comfort cooling to low temperature process cooling?
Resolution:
If the RTAA or RTUA was originally ordered at comfort cooling conditions, it is a fairly simple change to allow the chiller to run at low temperature conditions.
Control setting that need to be changed:
- Low water temperature EXV gain comp should be enabled
- Leaving water and low refrigerant cutout should be set for the proper glycol and leaving chilled water temperature.
The refrigerant piping between the RTUA and air-cooled condenser should be evaluated to ensure the piping is sized correctly for the lower LWT.
This does not apply to the RTWA ordered at comfort cooling temperatures. For low temperature and high condenser applications, the compressors are different and an oil cooler may have to be installed.
The RTWA, RTAA, and RTUA are all able to be run in ice-building mode with only a controls change. Please see the unit's IOM for more information. Literature links can be found in the following solutions: Service literature Service Literature and sales literature Pueblo Literature.
Notes:
Changes:
Other Question/Problem/Cause Statements:
- What needs to be done to change unit from comfort cooling to low temperature process cooling?
Facts:
- Air-Cooled Chiller (Pueblo) (RTAA 70-125 Ton)
- Compressor Chiller (Pueblo) (RTUA)
- Water-Cooled Chiller (Pueblo) (RTWA)
- Air-Cooled Chiller (Pueblo) (RTAA 130-400 Ton)
Document Identifier: DOC-82601
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.