SmartLock Fitting

SmartLock Fitting
SmartLock Fitting

SmartLock Fitting Review

There is another ACR fitting available that eliminates brazing in refrigerant systems called the SmartLock fitting. We will review the SmartLock fitting vs Brazed fittings in this article.

SmartLock Fitting Labor Savings

According to the manufacture the amount of time required to make a SmartLock fitting is 90% less than that of a brazed fitting. This means that the fitting only takes 10% the time required for a brazed fitting.

SmartLock Fitting saves ninety percent on labor
SmartLock Fitting saves labor

So, according to MCA, a 1/2” 90-degree elbow would take 0.40 hours or 24 minutes. This would translate into 2.4 minutes for a SmartLock fitting per the manufacture against the MCA factor of 1.0

No Flame, Fire Watch or Permit Required

One of the greatest benefits of any of compression type fittings like the SmartLock fitting is its lack of need for a flame to make the joint. The use of a flame in brazing adds to the cost due to the consumption of the gas, the need for a fire watch the additional paperwork of obtaining a hot permit.

SmartLock Fitting No Flame Fire Watch or Hot Permit
SmartLock Fitting requires No Flame, No Fire Watch or Hot Permit

No Special Tools Required

All that is required to make the SmartLock fitting is a standard crescent wrench or a torque wrench, as opposed to ZoomLock which requires a very expensive power actuated tool. This will save you on the capital cost to get started, or at least the expense of trying out this fitting on a small project to see if it is something you feel fits into your company’s method of installing ACR tubing.

SmartLock Fitting requires no special tools
No Special Tools required for the SmartLock Fitting

No Purging or Oxidation

During the brazing process is critical to provide a continuous purge to avoid oxidation. With the SmartLock fitting there is no flame, so there is no need to purge to avoid oxidation.

SmartLock Fitting requires NO Purging

Temperature Rating

The SmartLock fitting is rated to a temperature of 302 F, which is more than adequate to meet the discharge temperature of refrigerant R410A, which is can reach up or greater than 250 F

SmartLock Fitting Temperature Rating

Available Sizes

Most of the SmartLock fittings are available in the standard sizes including 1/4”, 3/8”, 1/2”, 5/8”, 3/4” and 7/8”, with a minimum order of at least a 100 pieces for the larger sizes of 1-1/8”, 1-3/8” and 1-5/8”. I would guess that after their market share grows in the U.S. this minimum order would disappear, or that your supply house would pick up the required minimum.

SmartLock Fitting Sizes
SmartLock Fitting Sizes

SmartLock Fitting Technology

The highlight of the this fitting is the method by which it attaches and seals itself to the underlying tubing. The fitting uses a metal Ferrell that pinches down on the tubing to make the seal, a metal on metal seal. Most other compression type fittings use some form of elastomeric gasket that has lower thresholds of tolerance on the conditions of pressure, temperature and the copper tube condition.

SmartLock Fitting Technology
SmartLock Fitting Technology

Return on Investment

There are basically three factors that determine whether the use of the SmartLock Fitting is feasible.

SmartLock Fitting Cost analysis
SmartLock Fitting Cost Analysis

These include the hourly labor rate that you pay your installers, the productivity factor of those installers, meaning how long it takes for them to braze in a fitting compared to that of the SmartLock Fitting, and lastly the material cost difference between a brazed fitting and the SmartLock fitting.

  1. Hourly Labor Rate
  2. Productivity Factor
  3. Material Cost Difference

The chart below is based on the following assumptions:

  • Based on purchasing a 1/2” 90-Degree Elbow for $3.00
  • SmartLock Fitting labor savings discounted off of a 1.0 factor of MCA for 1/2” 90-degree elbow
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To use the chart below, you would determine your hourly labor rate (#1), and then make an assumption about the percentage of labor (#2) you would save using the SmartLock Fitting, Where the intersection of the Hourly Labor Rate meets the Column based on assumed productivity is where you will find the most you should be paying (#3) for a SmartLock fitting in order to breakeven.

SmartLock fitting breakeven analysis
SmartLock Fitting Breakeven Analysis

Things to remember are that most contractors can install a 1/2” 90-degree elbow at a factor less than 1.0 of the MCA book value. This would require that the cost of the SmartLock fitting be less than the values in this chart.

Some contractors will pay more or less than the assumed $3.00 used in this example for a brazed ½” 90-degree elbow. Adjust according to your actual cost.


The SmartLock fitting comes with a 10-year warranty, while some of the other compression type fittings limit their warranties to 5 years.

No Leakage

The SmartLock fitting claims a zero leakage rate if you follow all of their installation procedure for the proper installation of their fitting. Of course with any fitting the proper installation protocol is always required. 

This is a one-time use fittings as are most other fittings like ZoomLock. In other words, if you make a bad connection you will have to cut out the fitting and use another one.

No Flaring

There is no need to make a flare for the SmartLock fitting as it is installed on the raw cut end of a piece of tubing. 

ACR Copper or Aluminum Tubing

The SmartLock fitting can be installed on either copper or aluminum tubing without the need for any special considerations, like coated aluminum.


You will need to determine if the cost of your labor is high enough to warrant paying the premium for the SmartLock Fitting. This will be based on the three basic factors of your Hourly Labor Rate, Productivity Factor and the cost difference between a brazed fitting and the SmartLock Fitting.

There are other considerations besides cost, and that is the safety factor of using the SmartLock Fitting in settings where the use of a flame may impact other aspects of the project, such as in a senior facility where the smell of smoke may heighten anxiety for the residents or where brazing in a wood structure causes concern of a fire.

Watch the below video to see just how easy the installation of a SmartLock fitting is.


See the following related articles;

ASHRAE Study on Mechanical Piping Joints

ZoomLock vs Brazed Fittings

Reftekk Piping Solution

ZoomLock Crimping Tool Review

ZoomLock Value Calculator

ZoomLock Cost Analysis

Lokring Fitting

Visit the SmartLock website here

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