Building Code Glossary
Refrigerating System: Building Code Definition
How the IRC 2009, IMC 2009 define refrigerating system, where the wording differs, and which chapters depend on the term.
On this page
Last updated September 7, 2026 · Definitions quoted from the 2009 International Codes as transcribed in this site's building-codes collection, with the source chapter linked for each quotation. Usage counts are computed over the chapters hosted here, one copy per code. The [ICC code library](https://codes.iccsafe.org/codes) publishes the current model text and the [ICC adoption maps](https://www.iccsafe.org/advocacy/code-adoption-maps/) show which edition a jurisdiction has adopted; those sources control.
Direct answer
Refrigerating system is a defined term in the International Residential Code (IRC) 2009, in Definitions. The code's own words are: “A combination of interconnected parts forming a closed circuit in which refrigerant is circulated for the purpose of extracting, then rejecting, heat. A direct refrigerating system is one in which the evaporator or condenser of the refrigerating system is in direct contact with the air or other substances to be cooled or heated. An indirect …” The IMC 2009 defines the same term with different wording, so the controlling text depends on which code governs the question in front of you — the comparison below sets the versions side by side. The term is used in 5 chapters of this corpus, most often in Definitions (IMC 2009), Refrigeration (IMC 2009), Definitions (IRC 2009). These pages transcribe the 2009 model text; verify the definition against the edition and amendments your authority having jurisdiction has adopted.
Content and cited inputs reviewed by Scott Barrington, Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.
What does this term mean?
Refrigerating System — IRC 2009, Definitions:
A combination of interconnected parts forming a closed circuit in which refrigerant is circulated for the purpose of extracting, then rejecting, heat. A direct refrigerating system is one in which the evaporator or condenser of the refrigerating system is in direct contact with the air or other substances to be cooled or heated. An indirect refrigerating system is one in which a secondary coolant cooled or heated by the refrigerating system is circulated to the air or other substance to be cooled or heated.
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Refrigerating System, and the wording is not identical — read the version that governs your question.
| Code | Where it is defined | Definition |
|---|---|---|
| IRC 2009 | Definitions | A combination of interconnected parts forming a closed circuit in which refrigerant is circulated for the purpose of extracting, then rejecting, heat. A direct refrigerating system is one in which the evaporator or condenser of the refrigerating system is in direct contact with the air or other substances to be cooled or heated. An indirect refrigerating system is one in which a secondary coolant cooled or heated by the refrigerating system is circulated to the air or other substance to be cooled or heated. |
| IMC 2009 | Definitions | A combination of interconnected refrigerant-containing parts constituting one closed refrigerant circuit in which a refrigerant is circulated for the purpose of extracting heat. |
Where refrigerating system is used in the code
The term appears in 5 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Definitions | IMC 2009 | 13 |
| Refrigeration | IMC 2009 | 9 |
| Definitions | IRC 2009 | 5 |
| Building Services and Systems | IFC 2009 | 1 |
| Heating and Cooling Equipment | IRC 2009 | 1 |
The term in use
How the code actually writes about refrigerating system, quoted from the 2009 text hosted here:
Joints and all refrigerant-containing parts of a refrigerating system located in an air duct of an air-conditioning system carrying conditioned air to and from human-occupied space shall be constructed to withstand, without leakage, a pressure of 150 percent of the higher of the design pressure or pressure relief device setting.
Refrigerating System compared with Refrigeration System
These two are the closest pair in the 2009 I-Codes: about 45 per cent of their defining words are the same. The code states both and compares neither, so the difference is worth naming.
| Wording unique to it | |
|---|---|
| Refrigerating System (IRC 2009) | forming, then, rejecting, direct, refrigerating, system, evaporator, condenser, contact, air, substances, cooled |
| Refrigeration System (IFC 2009) | containing, constituting |
Everything else in the two definitions is shared. If a project turns on which of the two applies, those words are the whole of the test — and a local amendment that edits one of them without editing the other moves the boundary between refrigerating system and refrigeration system.
The terms refrigerating system is built out of
The definition above leans on 4 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what refrigerating system covers:
- Refrigerant — IRC 2009: A substance used to produce refrigeration by its expansion or evaporation.
- Evaporator — IMC 2009: That part of the system in which liquid refrigerant is vaporized to produce refrigeration.
- Condenser — IMC 2009: A heat exchanger designed to liquefy refrigerant vapor by removal of heat.
- System — IFC 2009: An assembly of equipment consisting of a tank, container or containers, appurtenances, pumps, compressors and connecting piping.
Refrigerating System: what to open, and in what order
Every row is a document this term depends on. The ICC code library and the ICC adoption maps cover the middle rows.
| Check | Where | Confirmed |
|---|---|---|
| Read the definition in the adopted IRC | Definitions | |
| Read the definition in the adopted IMC | Definitions | |
| Re-check the requirement that uses it | Definitions (IMC 2009) | |
| Re-check the requirement that uses it | Refrigeration (IMC 2009) | |
| Re-check the requirement that uses it | Definitions (IRC 2009) | |
| Re-check the requirement that uses it | Building Services and Systems (IFC 2009) | |
| Confirm the dependent definition | Refrigerant | |
| Confirm the dependent definition | Evaporator | |
| Confirm the dependent definition | Condenser | |
| Local amendment to any of the above | Jurisdiction's amendment list |
A research aid, not a code determination. The authority having jurisdiction decides which edition and which amendments apply.
Where can you explore related guidance?
- Explore all glossary guidance
- Refrigerant: Building Code Definition
- Evaporator: Building Code Definition
- Condenser: Building Code Definition
- System: Building Code Definition
Sources and method
Definitions quoted from the 2009 International Codes as transcribed in this site's building-codes collection, with the source chapter linked for each quotation. Usage counts are computed over the chapters hosted here, one copy per code. The ICC code library publishes the current model text and the ICC adoption maps show which edition a jurisdiction has adopted; those sources control.
Source links
Frequently asked questions
What is the code definition of refrigerating system?
The International Residential Code (IRC) 2009 defines it in Definitions as: “A combination of interconnected parts forming a closed circuit in which refrigerant is circulated for the purpose of extracting, then rejecting, heat. A direct refrigerating system is one in which the evaporator or condenser of the refrigerating system is in direct contact with the air or other substances to be cooled or heated. An indirect refrigerating system is one in which a secondary coolant cooled or heated by the refrigerating system is circulated to the air or other substance to be cooled or heated.” The 2009 model text is reproduced here; the definition that binds your project is the one in the edition your jurisdiction has adopted, as amended locally.
Which parts of the code depend on refrigerating system?
In this corpus the term is used across 5 chapters, led by Definitions in the IMC 2009. Those are the sections whose scope moves if the definition is amended locally, so read them together with Chapter 2 rather than on their own.
What is a refrigeration system?
Refrigeration System is a separate defined term. The IFC 2009 defines it as: “A combination of interconnected refrigerant-containing parts constituting one closed refrigerant circuit in which a refrigerant is circulated for the purpose of extracting heat.” That is not the same as refrigerating system, which the IRC 2009 defines as “A combination of interconnected parts forming a closed circuit in which refrigerant is circulated for the purpose of extracting, then rejecting, heat. A direct refrigerating system is one in which the evaporator or condenser of the refrigerating system is in …” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
Related pages
- Refrigerant Safety Classifications: Building Code Definition
Refrigerant Safety Classifications — IMC 2009 definition: Groupings that indicate the toxicity and flammability classes in accordance with Section 1103.1.
- Refrigerant: Building Code Definition
Refrigerant — IRC 2009 definition: A substance used to produce refrigeration by its expansion or evaporation.
- Refrigerated Room or Space: Building Code Definition
Refrigerated Room or Space — IMC 2009 definition: A room or space in which an evaporator or brine coil is located for the purpose …
- Refrigeration System Classification: Building Code Definition
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- Refrigeration System, Mechanical: Building Code Definition
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- Refrigeration System, Self-contained: Building Code Definition
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