Leak detection: requirements for refrigerants

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Refrigerants (such as R134a, R407c, and R410a) are used in refrigeration and air conditioning equipment, including chillers, air conditioning units, and heat pumps. These fluids are a source of certain greenhouse gases (GHGs). With the goal of controlling and reducing emissions of these GHGs, regulations are becoming increasingly stringent regarding the leak detection of refrigerants.

We previously covered these regulations in a 2016 article as well as subsequent updates in another 2017 article.

We would like to focus on specific equipment: stationary (*) refrigeration, air conditioning, and thermodynamic equipment with an HFC (e.g., R134a) or PFC (e.g., CF4) charge greater than or equal to 500 tonnes of CO2 equivalent. These must be equipped with a permanent leak detection system.

A decree dated July 15, 2019, amended the decree of February 29, 2016, to clarify the implementation procedures for these systems.

(*) Stationary: equipment that is not normally in transit during operation, which includes portable self-contained air conditioners.

Mobile: equipment that is normally in transit during operation.

Prioritizing leak detection systems

Permanent systems for leak detection HFC systems to be implemented are completed and prioritized:

1. A permanent HFC leak detection system based on an indirect leak detection method (system no. 1) must be prioritized for implementation.

As a reminder, such a system measures at least one of the following parameters:

• pressure;
• temperature;
• compressor current;
• liquid levels;
• volume of the recharged quantity.

2. A permanent HFC leak detection system based on direct methods (system no. 2) may be implemented if the indirect leak detection system cannot be implemented for technical reasons.

For these first two systems, the alarm must notify the operator no later than when the leak results in the greater of the following losses: HFC mentioned below:

• 50 grams per hour;
• 10% of the fluid charge in tonnes contained in the equipment.

In addition to these first two systems, a new option is available if the implementation of the previous systems is not technically feasible:

The operator must then implement a permanent leak detection system that analyzes at least one of the following parameters:

• pressure;
• temperature;
• compressor current;
• liquid levels;
• volume of the recharged quantity.

This system is connected to an alarm for which the decree does not specify a trigger threshold, and a leak check must be performed every 3 months using a direct measurement method.

A study justifying the technical impossibility of implementing a permanent HFC leak detection system based on an indirect measurement (system no. 1) or direct measurement (system no. 2) method must be conducted.

Leak detection system tracking log

A tracking log for the permanent leak detection system in use must now be established. This log specifies:

• the fluids for which the permanent detection system is suitable;
• the list of maintenance operations intended to keep it in good working order;
• the results of the checks performed and, where applicable, the corrective actions to be taken.

Leak check frequency

The frequency of periodic checks for equipment with a charge greater than 500 tonnes of CO2 equivalent is specified according to the type of equipment (mobile or stationary) and the leak detection system in place:

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Conclusion

We advise you to review your refrigeration, air conditioning, and thermodynamic equipment containing more than 500 tonnes of CO2 equivalent in HFCs/PFCs with your maintenance department in order to:

• implement a tracking log for your permanent leak detection systems;
• conduct a study justifying the permanent leak detection system in place if it does not operate via indirect measurement;
• adjust the frequency of leak tightness checks based on the system implemented.

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