23 Series Screw Chiller Fundamentals
SER 275

This class is targeted at service technicians and facility managers who operate or service Carrier 23XR/XRV water-cooled screw chillers. This class will cover the chiller refrigeration cycle, compressor theory, drive theory, cooler heat transfer, and water-cooled condensers. Operation and function of the compressors, muffler, condenser, coolers, economizers, metering devices, oil concentrator and accessories are covered. You will learn how to analyze performance by recording and analyzing refrigerant and water pressures and temperatures. Service technicians will be able to distinguish between chiller and system problems and to quickly diagnose problems using service logs. The class also covers the unit controls and how to set up and adjust the controls for optimum system performance. In addition, recommended pre-start and startup procedures, and operational and field issues will be covered. These compressors have very few tear-down procedures; these procedures will be covered but are not demonstrated. The class consists of classroom instruction with a number of exercises to develop the skills taught in the class and some lab exercises using control simulators developing a working knowledge of the control system operation.

Who should attend this training

This class is for HVAC technicians with a minimum of one year of field experience or a graduate of an HVAC training program. Students are expected to have basic math skills and a basic understanding of HVAC tools (gages and digital thermometers) and troubleshooting equipment.

Learning Objectives

At the conclusion of this class each student should be able to:

• Set-up and adjust controls using Carrier instruction manuals
• Identify on machines, or from diagrams, the major components of a screw liquid chiller
• Describe from memory the operation of a 23XRV screw liquid chiller including start-up
• On a diagram be able to describe the refrigerant flow in a system including typical refrigerant conditions
• Measure refrigerant and water temperature delta T, LTD, and use them to analyze unit operation
• Using log sheets compare design and actual operating conditions and determine the corrective action which might be required
• Troubleshoot and identify system problems using data from operating log sheets and system operating conditions to determine unit and system problems
• Using the service manuals, list and describe the maintenance procedures

Training Methods Used

This course uses a combination of classroom lecture, videos, animations, tours in the training facility lab, demonstrations, practical labs on operating equipment and workshops to present the material. Student’s achievement of the learning objectives is determined by successful completion of the workshops, labs, homework, and final written and practical exam. Workshops are instructor guided exercises using the procedures taught in the lectures.

Topics Covered

• Overview of water-cooled 23XR/V screw chillers including the chiller’s refrigeration cycle, screw compressor, drive theory of operation, and cooler and water-cooled condenser. 
• Operation and function of the compressors, muffler, condenser, cooler, economizer, metering device, oil concentrator and accessories are covered. 
• Students will learn how to analyze performance and troubleshoot issues using refrigerant and water side conditions such as pressures and temperatures. 
• How to distinguish between chiller and system problems and how system issues affect the chiller. 
• Students will learn how to use the chiller control interfaces for machine setup and diagnostics and understand the chillers sequence of operation. 
• Review of recommended maintenance procedures and how site-specific conditions can affect maintenance requirements.

Completion requirements

To receive a certificate for this class, student must be present for the entire class, complete all workshops and labs and receive a grade of 70% (C+) on graded labs, homework and final.

Prerequisite requirements

None.

Suggested background

For technicians just entering the HVAC field or persons with no field experience, this course is most effective when preceded by SER024 Intro to HVAC Service, which introduces participants to fundamental concepts of both air conditioning and heating systems, including lab time with service test equipment and tools.

Materials to bring

No special equipment is required. We provide the appropriate safety equipment required by Carrier. If you are required by your company to use other PPE, you may bring that to class.

What you will receive

Students in this course will receive a course workbook, notepad and highlighter/pen.

Appropriate dress for this class

This class has a number of exercises that take place in the lab on operating units; participants should wear long pants, closed toed shoes and appropriate shirt, long or short sleeve. If your employer requires special dress which is more stringent than these requirements, this dress should be worn.

Class hours

Class starts at 8 AM and ends at 5 PM daily. Travel arrangements should be made accordingly.

Location & lodging

Carrier University is located at 5900 Northwoods Business Parkway, Charlotte, NC 28269. Lodging options can be found here.