A DIR includes several key sections that provide a thorough overview of the chiller’s condition, performance, and any potential issues. Each section offers valuable insights to technicians, supervisors, and customers. Below are the major sections of the DIR:
A. Chiller Overview
Provides detailed information about the chiller’s specifications and setup.
Content:
Model and Serial Number: Identification of the specific chiller being inspected.
Location: The site where the chiller is installed.
Key Specifications: Cooling capacity, operating voltage, and refrigerant type.
Manufacturer Details: Relevant information on the chiller's manufacturer and maintenance guidelines.
To update the information retrieved from Salesforce, raise a request to the service manager:
The requested changes will be reflected in the next time-generated AHP report.
It has been observed that, for example, a chiller asset tag may need an update in SF; it sometimes has the chiller SN instead.
B. Chiller Health Score
Chiller Health Score: An overall rating (e.g., percentage or grade) reflecting the chiller’s current condition and operational health.
How It Works:
Weighted Average: CGHI is a weighted average of parameters from the Chiller Operations Check (e.g., temperature, pressure, energy use).
Algorithm-Based: Specific algorithms calculate the CGHI during high-load periods for accurate performance evaluation.
Key Benefits:
Early Issue Detection: Identifies problems early for timely intervention.
Proactive Maintenance: Predicts service needs to prevent unplanned downtime.
Data-Driven: Supports informed decisions on repairs and optimizations.
C. Circuit-level Health Score
Circuit-level Health Score: A circuit-level rating (e.g., percentage or grade) of the 30 Series chiller that reflects a specific circuit’s current condition and operational health.
How It Works:
Weighted Average: CGHI is a weighted average of parameters from the Chiller Operations Check (e.g., temperature, pressure, energy use).
Algorithm-Based: Specific algorithms calculate the CGHI during high-load periods for accurate performance evaluation.
Key Benefits:
Early Issue Detection: Identifies problems early for timely intervention.
Proactive Maintenance: Predicts service needs to prevent unplanned downtime.
Data-Driven: Supports informed decisions on repairs and optimizations.
D. Observations and Recommendations (Chiller and its circuit)
The observations and recommendations section provides targeted insights and actionable guidance based on the chiller’s operational data. The observations and recommendations for the chiller and its circuit help the technician to take appropriate actions on the specific module of the 30 series chillers.
For the 30 Series chillers, you can also see the separate observations and recommendations for each circuit along with the overall chiller level. The below image is for your reference:
Each observations and recommendations section has mainly two items:
Observations: System-generated notes highlighting chiller health impacting parameters for technician review.
Recommendations: Actionable advice associated with each observation for system optimization based on the digital inspection findings.
E. Service Configuration
The service configuration section contains the operation setup and design parameters used to evaluate the chiller’s performance. These parameters are reflected here from AHP platform and CCN point. They are also configurable on AHP platform. To learn more about the design data configuration, click here.
The service configuration has the following parameters:
Type of Fluid: It indicates the fluid used in the chiller system (e.g., water, glycol mix). It affects heat transfer efficiency and system compatibility.
Delta T*: The temperature difference between entering and leaving water. It is a key indicator of system performance and cooling load.
Total Water Flow: It measures the volume of water circulating through the system. It is essential for ensuring adequate heat exchange and system balance.
Outside Air Temp: It is the external ambient temperature. It influences condenser performance and overall system efficiency.
Min Setpoint: The lowest temperature on which the system is configured to maintain. It helps prevent overcooling and protects equipment.
Max Setpoint: The highest temperature on which the system is allowed to reach. It ensures the system doesn’t underperform or exceed operational limits.
F. Chiller Operation Check
The Chiller Operation Check section contains the checklist of the parameters based on the global standards of operational inspections for individual chiller models. Each check is associated with a representative graph in the graphs section that provides more details.
Graphs show daily averaged data. For deeper diagnostics, the AHP portal provides detailed telemetry to understand the data better.
The detailed telemetry is also available now on the AHP mobile view.
Chiller Operation Check Highlights are included:
Algorithm-Based: Operational checks use specific algorithms.
Health Score: Determines the general health score; parameters with an asterisk (*) are weighted more heavily.
Load-Specific: Conducted only at specified chiller load profiles.
In the chiller operation check section, the parameters are grouped in their chiller’s unit. This section provides the following information for each parameter:
Normal Range: Specifies normal values and acceptable thresholds for each parameter.
% Hours in Range: Shows the percentage of time within the normal range, offering insight into performance stability.
Average Value when in/out Range: Shows the average values of the parameter when in/out range.
Each 30 Series chiller has different parameters for the chiller operation checks depending on their model family. Below are the different lists of the parameters based on their model family:
a. 30H-X WC Screw model family:
The 30H-X WC Screw chiller model family has the following parameters for the chiller operation check:
General
Setpoint accuracy (Cooling mode)
Z Multiplyer
Circuit A
Evaporator approach - Circuit A
Condenser approach - Circuit A
30 GX and HX: Discharge Superheat; 30 XA: Superheat
Compressor Discharge Pressure
Saturated Suction Temperature Check
EXV Positioning
Compressor A1
Differential Oil Pressure (deltaP) - Compressor A1
Compressor Motor temperature - Compressor A1
Run hours vs starts/stops - Compressor A1
Compressor A2
Differential Oil Pressure (deltaP) - Compressor A2
Compressor Motor temperature - Compressor A2
Run hours vs starts stops
b. 30R-M AC Screw model family:
The 30R-M AC Screw chiller model family has the following parameters for the chiller operation check:
General
Setpoint accuracy (CTRL Point difference)
Z Multiplier
Condenser Entering Airside Temp. (OAT)
Evaporator
Evaporator Entering Water Temp
Evaporator Leaving Water Temp
Circuit A
Evaporator approach
Saturated Suction Temp
EXV Positioning
Condenser Circuit A
Saturated Condenser Temp
Compressor A1
Run hours vs Starts
Compressor A2
Run hours vs Starts
Circuit B
Evaporator approach
Suction Temp
EXV Positioning
Condenser Circuit B
Condenser Entering Airside Temp. (OAT)
Saturated Condenser Temperature
Compressor B1
Run hours vs Starts
Compressor B2
Run hours vs Starts
c. 30MP WC Scroll model family:
The 30MP WC Scroll chiller model family has the following parameters for the chiller operation check:
General
Setpoint accuracy (Cooling mode)
Z Multiplier
Evaporator
Evaporator Entering Water Temp
Evaporator Leaving Water Temp
Circuit A
Evaporator approach
Saturated Suction Temp
EXV Positioning
Condenser Circuit A
Condenser Entering Water Temp
Condenser Leaving Water Temp
Condenser approach/Fouling
Compressor A1
Run hours, Starts (Compressor A1)
Compressor A2
Run hours, Starts (Compressor A2)
Circuit B
Evaporator approach (Circuit B)
Suction Temp
EXV Positioning
Condenser Circuit B
Condenser Entering Water Temp. (Circuit B)
Condenser Leaving Water Temp. (Circuit B)
Condenser approach/ Fouling (Circuit B)
Compressor B1
Run hours, Starts (Compressor B1)
Compressor B2
Run hours, Starts (Compressor B2)
G. Trend Chart
The Trend Charts section of the DIR provides a graphical representation of available parameters in the chiller operation check. The type of the graphical representation for the 30 Series chiller model family varies based on the parameters available for the particular model family in the chiller operation check section.
These visualizations help the technicians identify the possible issues so they can take correct actions to rectify them before any major fault occurs.
Graphs display daily averaged out data. For deeper diagnostics, the AHP portal provides detailed telemetry to understand the data better.
The detailed telemetry is also available now on the AHP mobile view.
Trend Chart 1: Evaporator Entering and Leaving Water Temperature and Setpoint Trend |
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Trend Chart 2: Evaporator and Condenser Approach and Threshold Trend |
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Trend Chart 3: Oil Pump Pressure Threshold Trend |
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Trend Chart 4: Oil Temp, Motor Winding & Compressor Discharge Pressure Trend |
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G. Alarm Summary
The Alarm Summary provides details on the five most recent alarms based on the chiller control manuals. Here’s what’s included for each alarm:
Alarm Code: Unique identifier for the alarm.
Time: Timestamp when the alarm was triggered.
Description: Brief explanation of the alarm.
Type of Alarm: Specifies the category or severity of the alarm.
For a full alarm history going back up to one year, you can access it on AHP: hvac.abound.carrier.io
Importance:
Highlight the role of alarm history and data logs in maintenance and troubleshooting.
Techniques:
Analyze alarm logs to identify and address frequent issues or recurring alarms.
Use operational logs to monitor system performance and note deviations.
Workshops:
Interactive alarm analysis with real logs.
Simulations to practice logging and reporting based on DIR data.
H. Chiller Logs
The Chiller Logs provide a record of the key chiller parameters that technicians enter the Salesforce. These logs capture data from the specific point in time when the peak load was reached during the reporting period.
Purpose: To document chiller performance at peak load.
Data Entry: Technicians input the required parameters into Salesforce.
Timing: Logs reflect the moment of highest load within the reporting period.
Ensure accurate and timely logging to support effective analysis and reporting!
