Recent Blog Posts

Pipe Corrosion (IIAR 6, Part 13)

February 18th, 2020

In Part 12 of our series on ANSI/IIAR 6-2019 we examined the ITM requirements related to pressure vessel corrosion. While many of the same principles apply, it is fitting to explore unique considerations when inspecting ammonia pipe. Table 11.1 requires non-insulated ammonia pipes to be inspected annually for pitting and surface damage (Inspection Item A). […]

Vessel Corrosion (IIAR 6, Part 12)

February 4th, 2020

Pipe and vessel corrosion has been a regular cause of ammonia releases since the invention of the vapor compression refrigeration cycle. For this reason, it is appropriate that ANSI/IIAR 6-2019 prescribe the minimum requirements for inspection, testing, and maintenance of pressure vessels. ANSI/IIAR 6-2019 Table 10.1 requires that non-insulated pressure vessels be inspected annually for […]

Testing Compressor Safety Devices (IIAR 6, Part 11)

January 21st, 2020

Is it acceptable to test a high discharge pressure cutout (HPCO) by lowering the setpoint? Maybe. ANSI/IIAR 6-2019 §6.1.1 prescribes the allowable methods for testing a compressor HPCO which is required annually per Table 6.1. Depending on the type of pressure limiting device being used, allowable methods differ. Electromechanical Switch Electromechanical switches are widely used […]

The Tables! (IIAR 6, Part 10)

January 14th, 2020

Chapters 6-15 of ANSI/IIAR 6-2019 primarily consist of tables which summarize the minimum frequencies for the required ITM tasks. Each chapter addresses a different category of equipment: 6 – Compressors 7 – Refrigerant Pumps 8 – Condensers 9 – Evaporators 10 – Pressure Vessels 11 – Piping 12 – Safety Systems 13 – Overpressure Protection […]

Qualified Inspectors (IIAR 6, Part 9)

December 10th, 2019

Who is allowed to perform inspections on an ammonia refrigeration system? ANSI/IIAR 6-2019 §5.4.2 succinctly states that “Equipment inspections shall be performed by a qualified inspector(s)“. According to the definition in Chapter 2, a Qualified Inspector is “A person who is experienced with closed-circuit ammonia refrigeration systems, has knowledge of the process, and has demonstrated […]