Supermarket Freezer

The Definitive Guide to Leak Rate Reduction

In Articles by Keilly Witman1 Comment

Cost of Refrigerant

Five Simple Steps to Reduce Your Refrigerant Leak Rate

With the supermarket industry’s minuscule profit margins, reducing costs can be more powerful for the bottom line than increasing sales, and there are few cost line items as ripe for improvement as refrigerant leaks.

Reducing refrigerant leaks may seem like a daunting task. Breaking that task down into manageable parts can reduce complexity and quickly lead to significant results. There are at least five parts to a successful leak reduction program: leak repair, leak detection, leak prevention, measuring/tracking performance, and goal-setting. These five parts work together to address refrigerant leaks from all angles. Once you have the basics down, there are many opportunities to add elements to the plan, but it’s best to start off simple, allow everyone to experience success, and then move on from there.

1) Leak Repair

Those wanting to reduce refrigerant leaks may find this first point too obvious: to leak less, you must repair your leaks.

The most over-used phrase in refrigerant management is, “Of course, we repair all leaks.” Yet the typical supermarket in this country leaks about 1,000 pounds of refrigerant.

What’s wrong with this picture? Most leaks do eventually get repaired, but when? How often do you wait to repair a leak until a store closes, until a service technician can fit you in, or until the leak gets so bad that your cases won’t hold their set temperature? Do you only repair leaks once your leak rate exceeds the leak repair threshold in the EPA’s refrigerant regulations? Do you shut down or valve off equipment that cannot be repaired immediately? Unless your answers to those questions were never, never, never, never, and yes always, you need to change your approach to leak repair if you want to make headway.

The best of the best when it comes to leak rates understand this already. Every supermarket company that I’ve run into with a leak rate below 10% has a “no leak tolerance” policy. That means that you repair every leak immediately. It doesn’t matter if it’s lunchtime and the store is packed. It doesn’t matter if the store manager screams. It doesn’t matter if the leak is in an underground pipe. Immediately means immediately. You cannot possibly sell enough product from any display case that is leaking to warrant postponing a repair.

2) Leak Detection

Right on the heels of leak repair, and working hand-in-hand with it, is leak detection. Do you first know that you have a leak when food gets too warm in a display case? You’ve already leaked too much refrigerant if that is your leak detection method. The faster you detect a leak, the less refrigerant you leak.

There are multiple leak detection options, ranging from sophisticated automatic leak detection systems to small handheld leak detectors.

Stores with high leak rates may warrant a period of monthly leak inspections until the leak rate is brought under control. After that, quarterly inspections are usually enough for early detection. Yes, inspections cost money, but inspections pay for themselves in reduced refrigerant costs.

Supermarket companies with impressively low leak rates mandate that every leak repair event ends with a store “walk-through” with a leak detector before the service technician leaves the store. The walk-through can usually be completed while the technician is waiting for the repaired equipment to come back up to normal operating conditions before completing the follow-up leak repair verification test that is required under the EPA’s Section 608 regulations.

3) Leak Prevention

Most companies will see a significant improvement in their leak rates with a no leak tolerance policy and a systematic approach to leak detection. But if that’s where your plan stops, you are missing out on the most significant way to reduce environmentally harmful and expensive refrigerant leaks: refrigeration technology that is designed with leak prevention in mind.

Secondary systems, for example, use less refrigerant, so there is less refrigerant to leak, and the smaller refrigerant charge is confined to the machine room where leaks can be detected and repaired faster. In addition to being characterized by low leak rates in general, secondary systems also maintain low leak rates for a longer period of time after installation. Loop piping, reducing the number of piping joints, and valve caps are other examples of ways to prevent leaks within your equipment.

4) Measuring / Tracking Performance

The next two parts of any respectable leak reduction plan are not as obvious as leak repair, leak detection, and leak prevention. Very few food retail companies set annual refrigerant-related goals and measure performance; yet these same companies measure and set goals in most other areas of their business. They adhere to the old adage that you can’t improve something that you don’t measure. So why wouldn’t you handle refrigerant leaks the same way?

The EPA’s GreenChill Partners are the best example of the value of the “measure – set goals – measure again” philosophy. While the national average leak rate for supermarkets is 25%, GreenChill partners have an average leak rate of around 12-14%, even though the program measures the bare bones: charge size and pounds of refrigerant leaked. New GreenChill partners report that the very act of collecting data on the amount of refrigerant in their equipment and the amount leaked across their company led to immediate leak reductions.

You could measure a multitude of performance factors related to refrigeration, but the following four are the basics.

Company-wide Annual Leak Rate

What is your leak rate across all your refrigeration and air conditioning equipment in all your stores for the calendar year? If you don’t know that number, and many don’t, you have to figure it out. The metric is comprised of the amount of refrigerant in all of your refrigeration and air-conditioning equipment divided by the amount of refrigerant leaked from that equipment in the calendar year.

Corporate Average Leak Rate (%) = (All Refrigerant Leaked / Refrigerant Contained in All Equipment) × 100

Because every supermarket in the country is required by law to have a record of how much refrigerant is in each store’s refrigeration and air conditioning equipment and how much refrigerant is leaked from that equipment, it shouldn’t be difficult to put the pieces in place to do this calculation.

Pounds of Refrigerant Leaked

The leak rate is not the end all and be all, however, because slavish adherence to leak rates as a measure can lead to mistakes. Taking a look at the pounds of refrigerant leaked per store can help you prioritize your investments in leak reduction activities. For instance, you might have two stores with a 70% leak rate, but one store is leaking 3,000 pounds of refrigerant and the other is leaking 300. You’d want to prioritize the store that is leaking 3,000 pounds of refrigerant, of course.

Leak Repair Response Time

Leak repair response time is a measure of how fast your technicians respond to a leak repair request. If you have an automatic leak detection system in place, you’d measure the time between the alarm and the service technician response. You can define “response” in your own way; for instance, arrival of the tech at the store, triaging the leak by phone, or when the contractor deploys a technician to the store. This is measured in minutes. There is no supermarket industry average for this number, as far as I know, and there is no rule of thumb on what exactly you should measure. Some companies break alarms into categories like leak size, i.e. catastrophic leaks, small leaks, etc., or by leak location, i.e. compressor, display case, etc. Then they measure the response time for each category. Others just measure the average time from year to year and then try to improve it.

Time to Repair Leaks

The average time to repair a leak is measured like the leak repair response time. Be prepared for your service contractor to argue that this measure is unfair, because different types of leaks require more or less time to repair. The point is to look at the annual average across the company, which will likely include multiple contractors. That way, you are measuring the success of the processes you have in place, rather than the repair time for individual events that are likely not comparable.

5) Set Goals

After measuring whatever you feel you need to measure, the next step is to set goals for improvement. Ask yourself first what you want to achieve. You might feel that constant improvement is the priority, rather than the actual numbers. If that’s the case, a 10% improvement in leak rate and pounds of refrigerant leaked is considered achievable on an annual basis. Of course, that depends on your starting point. If your corporate-wide annual leak rate is 50%, you should be able to reduce that by 20-25% in one year. If your starting leak rate is below 12%, a 10% reduction is probably the most you should hope for.

If your goal is an actual number, for instance a target of a 15% corporate-wide annual leak rate, which is a respectable average leak rate, you’d want to determine how long you want to take to achieve that number and then determine the level of improvement needed each year to get where you want to be in the end. It’s harder to determine a target for response time and the time to repair a leak, because there are no industry averages.

If your goal is something bit more ephemeral, like being among the industry’s best, for instance, you’ll want to shoot for a corporate-wide annual leak rate below 10%. Again, in this case, the lack of data on response time and time to repair makes it difficult to pinpoint a goal for these performance factors.

Refrigerant Leak Management is Good Business

In conclusion, taking a systematic approach to refrigerant leak management is about more than reducing leaks. It’s good business management. It’s no accident that reducing your refrigerant leaks, like every other aspect of good business management, results in a better bottom line.

Are You Ready for 2019?!?

Changes are coming to EPA Section 608 in 2019. Download our free checklist to learn what simple steps you can take to maintain compliance.

Download the Refrigerant Compliance Checklist

Comments

  1. In a recent position, in over a year, I had an opportunity to research commercial comfort cooling systems which were originally manufactured with NO functional access ports, only saddle tees, minus their cores. The megaohm readings of the compressor windings were in better shape than those units with access ports that were only a few years old. These “portless” units were 20 to 30+ years old.

    In the early 80’s, I worked as a troubleshooter for an HVAC equipment manufacturer. This was approximately the same time the industry decided to reduce costs by using flared caps, plastic caps and using “O” rings for refrigerant seals. Most people are unaware that access valve cores, and other components, are designed to leak to lubricate their “rubber” seal(s).

    Being a former instructor of the HVAC trade, I had an opportunity to test multiple electronic leak detectors of the students. The majority were useless, even the one I originally purchased just out of trade school which, at the time, the most expensive on the market. The saving grace was, I did not calibrate it as the manufacturer had instructed. Until recently, no leak detector had ever beat it.

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