Part 4: Refrigeration Equipment Installation for New Walk-In Cooler
The last couple of weeks we have gone over what needs to be considered in the planning process of buying and installing a new walk-in cooler or freezer. We try our best to make it as easy as possible. It is a custom made-to-order box for your specific needs so we try to be clear and concise throughout the process. Now that the pre-planning has happened and the box has been built it is time to install the equipment that makes it cold.
Installation of Refrigeration:
Evaporating Coil:
The evaporator is installed in the walk-in box. If it is a large box it can have more than one evaporator. It is almost always attached to the ceiling of the walk-in and there are a variety of styles. The most common style of evaporators is the low profile evaporator.
Note: The evaporator will need space around it for air to flow freely into and out of it. Nothing can be piled up close to it because it may restrict the airflow and cause the coil to freeze.
Condensing Unit:
Installing the condensing unit requires a little forethought before getting to the installation part of the project. This is determined during the quote process but we’ll go over a few extra details so you are empowered with knowledge. Where the unit is going to be may change what condenser is being considered for the project but for the vast majority of projects an air cooled condensing unit is the best option in almost all situations. Below are a few options for where to put your condensing unit.
Roof Condenser:
A rooftop is the ideal place for an air cooled condensing unit. It is safe from being hit by cars or vandalized on the roof and is not an eyesore for your customers. Provided you have a 1/12 roof pitch or less, a condenser can be easily installed on a roof without racks or special roof jacks. The only downside to the roof installation for your walk-in is that you will require a licensed roofer to seal the penetration for the refrigerant lines and it requires a crane to set the unit.
Ground Condenser:
If the roof is not an option for installation of an air cooled condensing unit, the ground is the next best option. The condenser on the ground will use the outside air to cool the refrigerant just as it would on the roof so it will be as effective as a roof top installation. Plus you won’t need a crane or a roofer to repair your roof if you go with this option.
Condenser on the walk-in roof:
Sometimes there are no other options but to have your air cooled condensing unit on the roof of the walk-in. If your walk-in is completely in an air conditioned space including the condensing unit, it is fine. The condensing unit will get all of the cool air it needs and operate efficiently. The downside to this option is that it does create heat in an air conditioned space and that heat will have to be taken care of by your air conditioning. For most smaller systems this extra heat is not really an issue for the A/C.
Condenser in attic:
This is really the worst place for an air cooled condensing unit. During the endless summer months in Texas the condensing unit will keep heating up the attic to the point at which it can no longer work. Attics can easily be up to 125° and air cooled condensers are not designed to work at the temperature. I say air cooled condenser because there is another option other than air as a means to vent heat. Another less frequently used option is a water cooled condenser. This style of condenser is not dependent on the surrounding air temperature to keep it operating. It has a flow of water that keeps the system cooled. The downside to this is that you will need water flowing through the system when it is running and this often yields a lot of wasted water. It is fairly rare to see this type of refrigeration condenser unless it is in a large building or complex with a cooling tower so the water can be used again.
Drain Piping:
Unknown to many, the evaporator condenses water on its coil. Just like moisture in the air condenses on the outside of a cold glass it also collects on the evaporator coil. The evaporator coil in a cooler operates at 25° when it is cooling. Moisture in the air is going to condense on that coil, often freezing to the coil. During the defrost cycle the evaporator coil is allowed to get above freezing and the ice melts dripping down into the pan at the bottom of the evaporator. The pan drains into a pipe that either goes to a sewer drain or it will go to a pump if there is nowhere to drain the water. The pump will take the drain water to a sink or somewhere it can be drained.
Refrigeration Piping:
Once the evaporator and condenser are in place, our technicians will connect the two units together with copper air-conditioning and refrigeration pipe often referred to as ACR. The copper connections are not soldered like plumbing because the pressure and temperatures that a refrigeration system operates at are much more extreme than conventional plumbing for water. A process called braising is used to connect the refrigerant lines and it withstands pressures far higher than the 100~ PSI city water is provided at. To prevent oxidation inside of the refrigerant lines, nitrogen must displace the air in the pipes when braising. If nitrogen is not pushing the air out, black soot will form as the copper inside the pipes oxidizes. The pipes are insulated to prevent condensation. A vacuum is pulled on the pipes, evaporator and condenser to remove moisture and non condensables from the system and then it is charged with refrigerant. Once the electrical is terminated it is ready to be started up.
That’s it! You have a new walk-in cooler or freezer from Tri-Point Refrigeration. You can start filling it with all of your product and move to the next stage of your business: Making yummy things! Yay for my tastebuds!
Want a walk-in cooler, freezer or combo box? Give us a call. Call 512-651-4565 in Austin and (806) 787-4985 in Lubbock, Texas Or Visit our website at https://www.tripointrefrigeration.com