During the installation of a new walk-in cooler or freezer, it is imperative the box remain square and level during the assembly of its panels. If the corners are not kept square and the floor not level, the panels will not fit together, leading to major issues as the box is being built. Even small inaccuracies will grow as the panels are assembled. These inaccuracies may not seem to be an issue as the panels are fit together, but they will lead to other panels not fitting properly and present major issues for completing the construction of the box.

First, always start with a level surface. If the floor is not level, two recommended techniques to level the floor are using self-leveling epoxy and/or asphalt shingles. It may be tempting to rush this part of the project in order to begin building the box, but it is important to get this right first before proceeding. It’s like building a wall — the base is the most important part of the project. Get it right and the wall goes up smoothly. Get it wrong and the wall is a mess.

Keeping the corners square is extremely important. Again, if the corners are not kept square, the panels will not fit together properly, and it will be a struggle to build the box. To make sure the corners are square, use a general mathematic formula that was learned back in high school: the Pythagorean theorem. For a right angle triangle it is:

a² +b² = c²

To make it simpler to remember and apply, substitute real numbers, using 3, 4, and 5:

3²(9) + 4²(16) = 5²(25)

The 3-4-5 triangle is a great way to make sure the corners are square and the panels at a 90-degree angle (see Figure 1, top). If one side of a triangle measures 3 feet and the adjacent side measures 4 feet, then the diagonal between those two points must measure 5 feet in order for it to be a right triangle. High school math really does have some real-world benefits.

Using a chalk line, you can lay out the corners on the floor and keep the panels square. Pick one leg of your panel and measure out 3 feet from the corner. Put a mark on the floor at the 3-foot point. Now, measure the adjacent floor from the same corner to 4 feet and put a mark there. Then, measure the distance between the two marks. If it is 5 feet, then you have a perfectly square corner. If the measurement is less than 5 feet, the angle is too small (<90°) and needs to be opened up a bit. If it is more than 5 feet, the angle is too big (>90°) and needs to be closed some. If needed, you can also use the measurements of 6-8-10.

Installing refrigeration systems will require a technician to not only be proficient in the refrigerant cycle and all of its components, but also will require a technician to be knowledgeable in many other trade crafts.