1 HVACR318 – Refrigeration II International Mechanical Code Relating to Refrigeration

2 International Mechanical Code IMC is broken down into chapters and sections. The chapters and sections are in numerical order. It is important for you to be able to quickly identify chapters and sections when you are looking for something. IMC is broken down into chapters and sections. The chapters and sections are in numerical order. It is important for you to be able to quickly identify chapters and sections when you are looking for something.

3 Chapter 11 of IMC 2003 Governs the installation, design, construction and repair of refrigeration systems that use the vapor/compression refrigeration cycle. Governs piping, pressure vessels, pressure relief devices. Permanently installed devices are considered part of the system they are attached to. Governs the installation, design, construction and repair of refrigeration systems that use the vapor/compression refrigeration cycle. Governs piping, pressure vessels, pressure relief devices. Permanently installed devices are considered part of the system they are attached to.

Factory Built Equipment Factory built equipment that meets UL 207, 412, 471, or 1995 requirements, and that are self contained, are considered to meet code if installed and serviced in accordance with manufactures directions.

Protection All components of a refrigeration system that could be damaged must be protected in an approved manner.

Water Connections Water connections to a refrigeration system must be made in accordance with this code, and the International Plumbing Code.

Fuel Gas Connections Fuel gas connections for refrigeration systems must be made in accordance with the International Fuel Gas Code, as well as the International Mechanical Code.

Maintenance Mechanical refrigeration systems must be maintained in proper operating conditions and free from excessive oil, dirt, and waste; excessive corrosion; and other debris and leaks.

9 Section 1102 Section 1102 of the IMC describes the system requirements. − says refrigerants cannot be mixed. − addresses refrigerant purity. − addresses recovery − addresses reclaiming refrigerants. Section 1102 of the IMC describes the system requirements. − says refrigerants cannot be mixed. − addresses refrigerant purity. − addresses recovery − addresses reclaiming refrigerants.

10 Section 1103 Section 1103 talks about refrigerant system classification. −Starts with and occupancy classifications. Section 1103 talks about refrigerant system classification. −Starts with and occupancy classifications.

11 Section Occupancy Institutional – disabled, debilitated, or confined occupants that can not readily leave. Public assembly – large numbers of people who can not quickly leave. Residential – permanent provisions for sleeping, eating, cooking, and sanitation. Institutional – disabled, debilitated, or confined occupants that can not readily leave. Public assembly – large numbers of people who can not quickly leave. Residential – permanent provisions for sleeping, eating, cooking, and sanitation.

12 Occupancy Commercial – Transact business, receive and ship goods, receive personal service and food. Large mercantile – over 100 persons congregate above and below street levels to purchase merchandise. Commercial – Transact business, receive and ship goods, receive personal service and food. Large mercantile – over 100 persons congregate above and below street levels to purchase merchandise.

13 Occupancy Industrial – Not open to the public. Access to authorized persons are controlled. Used to manufacture or store goods such as chemicals, food, ice, meat, or petroleum. Mixed Occupancy – occurs when two or more classifications come together. Industrial – Not open to the public. Access to authorized persons are controlled. Used to manufacture or store goods such as chemicals, food, ice, meat, or petroleum. Mixed Occupancy – occurs when two or more classifications come together.

14 Section System Classification Systems are classified based on the probability of refrigerant leaks. −Low probability systems −High probability systems See table for classifications and refrigerants. Systems are classified based on the probability of refrigerant leaks. −Low probability systems −High probability systems See table for classifications and refrigerants.

15 Section 1104 Addresses maximum allowable refrigerant quantities. See table for guides. Addresses requirements for mechanical rooms. Addresses maximum allowable refrigerant quantities. See table for guides. Addresses requirements for mechanical rooms.

16 Section Gives definitions for volume calculations. Noncommunicating spaces are neighboring rooms or spaces that do not have any permanent openings connecting them and do not share an HVAC system. Gives definitions for volume calculations. Noncommunicating spaces are neighboring rooms or spaces that do not have any permanent openings connecting them and do not share an HVAC system.

17 Section Communicating spaces do share a permanent opening and share an HVAC system. Air can easily move from one location to another. Plenums – When the area above a ceiling is used as a supply or a return plenum these areas are included in the volume calculations. Communicating spaces do share a permanent opening and share an HVAC system. Air can easily move from one location to another. Plenums – When the area above a ceiling is used as a supply or a return plenum these areas are included in the volume calculations.

18 Section 1105 Section 1105 talks about machinery rooms and the requirements for leak detection, ventilation and shared use. Refrigerant detectors must be installed per International Fire Code. Open flames from fuel burning appliances are not allowed unless combustion air is ducted from outside. Section 1105 talks about machinery rooms and the requirements for leak detection, ventilation and shared use. Refrigerant detectors must be installed per International Fire Code. Open flames from fuel burning appliances are not allowed unless combustion air is ducted from outside.

19 Section Mechanical ventilation must be provided unless the mechanical room has adequate free openings. Mechanical ventilation must not discharge air closer than 20 feet from property lines and building openings. Makeup air must be provided to replace exhaust air. Mechanical ventilation must be provided unless the mechanical room has adequate free openings. Mechanical ventilation must not discharge air closer than 20 feet from property lines and building openings. Makeup air must be provided to replace exhaust air.

20 Section Under normal conditions the mechanical ventilation system must exhaust the larger of: −.5 cfm per square foot of mechanical room area. −A volume required to limit room temperature rise to 18°F., taking into account the ambient heating effect of all machinery in the room. Under normal conditions the mechanical ventilation system must exhaust the larger of: −.5 cfm per square foot of mechanical room area. −A volume required to limit room temperature rise to 18°F., taking into account the ambient heating effect of all machinery in the room.

21 Section Under emergency conditions (refrigerant leak or fire), the ventilation system must exhaust the air according to the following formula: Q = 0.07 x √G −Where Q = CFMs and G is refrigerant in pounds of the largest system in the mechanical room. Under emergency conditions (refrigerant leak or fire), the ventilation system must exhaust the air according to the following formula: Q = 0.07 x √G −Where Q = CFMs and G is refrigerant in pounds of the largest system in the mechanical room.

22 Section Termination of relief devices inside the mechanical room must be: −above grade. −outside the structure. −no less than 15 feet from other grade. levels −not less than 20 feet from any window, ventilation opening or exit. Termination of relief devices inside the mechanical room must be: −above grade. −outside the structure. −no less than 15 feet from other grade. levels −not less than 20 feet from any window, ventilation opening or exit.

23 Section 1106 Covers mechanical room special requirements.

24 Section Piping This section covers refrigerant piping. All piping must be installed in accordance with this section. The primary purpose of this section is to prevent leaks and damage to pipes. This section covers refrigerant piping. All piping must be installed in accordance with this section. The primary purpose of this section is to prevent leaks and damage to pipes.

25 Section Piping Materials: –Steel –Copper and Brass –Copper tubing –Copper tubing joints – must be brazed, not soldered. –Aluminum tubing Piping Materials: –Steel –Copper and Brass –Copper tubing –Copper tubing joints – must be brazed, not soldered. –Aluminum tubing

26 Section If joints and tubing are put into air ducts (DON’T DO THIS!!!) they must be able to withstand leaks at 150% higher than rest of system or any pressure relief setting.

27 Section Liquid receivers must be installed on all systems with 100 pounds or more of refrigerant.

28 Section 1108 Section 1108 talks about pressure testing refrigeration systems. The primary purpose of this section is to prevent leaks. Tests should be completed on both low and high pressure sides of system. Must be done with an inert gas such as nitrogen. Does not change pressure with temperature. Section 1108 talks about pressure testing refrigeration systems. The primary purpose of this section is to prevent leaks. Tests should be completed on both low and high pressure sides of system. Must be done with an inert gas such as nitrogen. Does not change pressure with temperature.

29 Section 1109 Talks about periodic testing requirements. Testing must be performed on the following upon request from a code official: −Treatment and flaring systems −Devices needed to operate the equipment −Fans and associated emergency ventilation systems −Detection and alarm systems Talks about periodic testing requirements. Testing must be performed on the following upon request from a code official: −Treatment and flaring systems −Devices needed to operate the equipment −Fans and associated emergency ventilation systems −Detection and alarm systems

30 Notes on Code International Mechanical Code is used in Connecticut. The BOCA code is used in MA. Each town or municipality has the right to add requirements to the code. Remember EPA requirements as well. International Mechanical Code is used in Connecticut. The BOCA code is used in MA. Each town or municipality has the right to add requirements to the code. Remember EPA requirements as well.

31 Notes on Code The CT licensing exam is open book and you will be given a list of code books to bring. Make sure you have the correct version. Current CT code is Update your code books every time a new version comes out. The CT licensing exam is open book and you will be given a list of code books to bring. Make sure you have the correct version. Current CT code is Update your code books every time a new version comes out.