Freezing a Freezer
It’s the very end of fall, bordering on winter, and we’re going to look at air conditioners and refrigeration. Every year, someone learns the hard way that you both can and cannot run an air conditioner in the middle of winter. Let’s get to it before someone else learns a hard, expensive lesson.
Who Runs the AC in WINTER?
Someone out there will ask, so let’s head it off sooner than later. In an ideal world, you could pull in fresh, outside air, particularly when it’s cooler outside to cool your facility. This works in homes and even small businesses, but there’s challenges when you move into specialist industries and larger scale operations. Hospitals can’t just open the windows, as it can expose the patients to bacteria, viruses, and allergens. Restaraunts can’t leave their frozen food up to mother nature’s whims to keep it cold and safe. Large data centers need to be sterile and cool year-round, to the point that the air outside cannot easily keep up against the heat generated inside. Manufacturers in numerous industries need cool areas, for chemical work, storage, freezing food, and so on.
In all of these cases, nature is too unpredictable, too unreliable, or just too complicated to fulfill our needs. These places need to run air conditioning and refrigeration even through the coldest and darkest of winters.
The Freezing Problem
Regardless of application, all refrigeration systems have one big nemesis wherever cooler weather is involved: ice. The icing problem can occur in numerous places throughout a refrigeration system. Ice can build up on the coolant lines, it can build up on the coils, it can seize up the compressors and fans, and it can ruin your day. This can happen at any time of year, but its worst in the winter.
During the summer months, it’s usually hot enough outside to melt the ice before it becomes a problem. The hot air is enough to melt the ice as it forms or keep the hardware just far enough above freezing to prevent ice formation in the first place. During the colder months however, the air is already cold. The refrigerant lines are cold. Everything around the refrigeration system is going to be a little bit colder. Cold + cold = more cold.
This becomes a problem with water in the air. When ice freezes, it expands and pushes against whatever is around it. It’s like an explosion in slow motion. Ice just destroys whatever obstacles are in its path. Rocks, iron, and steel are no obstacle to ice. You can see this in any regions which experience cold-weather, like Pennsylvania, Connecticut, and New York, among others. There’s constant roadwork around these areas, because we’re constantly replacing our roads. Water gets down into the asphalt and concrete during the winter, it freezes, expands, and pushes against the roads from within, beneath, and all sides. Under these forces, the roads crack, form potholes, and break down to little more than dirt roads without the ruts.
These same effects occur with all refrigeration systems. Air conditioners, chillers, refrigerators, and everything like them is susceptible to freeze over.
What Do you Do?
If you’re installing a new system: make sure it is appropriately resistant to cold weather.
If you already have a system: make sure it is appropriately equipped for cold weather.
If you don’t know, ask your managers or HVAC Specialist to check on it for you. In most facilities that run the refrigeration systems through the winter, you’re probably already taken care of.
Seriously, What is the Fix?
Check back on Monday for our next post on all your defenses against ice and mother nature during the winter months!