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As cold weather begins to set in across the country, we often begin to worry about the threat of snow. When we think of snow, we often think about how it is going to affect the roads. We worry about schools being closed, or how dangerous the roads will be. However, we also need to be concerned about how snow and ice can affect our HVAC units.

Knowing How Much Ice is Normal

First, it is important to understand not all snow and ice build up on your HVAC system is harmful. In fact, if you have a heat pump, some ice on your outdoor unit is a normal part of operation, especially on extremely cold days.

Heat pumps work using a refrigerant that effectively absorbs heat from the surrounding air. As the refrigerant absorbs heat, moisture from the atmosphere builds up on the processing coils. When outdoor temperatures are extremely low, like at or below zero degrees Fahrenheit, that moisture instantly freezes, creating layer of ice.

While this ice may cause your system to run a bit slow during extreme temperatures, it isn’t anything to be concerned with. Everything should return to normal once the temperatures begin to rise.

Ice buildup, while normal, is still rather rare. Most modern units are designed with an automatic defrost feature. When the unit senses ice buildup, most systems will switch to a heat-distribution that works to melt the ice off ht coils. The process takes about half an hour, and  backup heat will keep your house warm during this process.

When Snow and Ice Can Cause a Problem

Some ice buildup on the outside unit is generally no big deal. However, when snow builds up around the outside unit or ice forms on top of the HVAC components, airflow can be restricted. This insufficient airflow causes your unit to work harder, causing stress on the system. It increases your energy use and wears on the system.

As snow builds up and ice crusts your outdoor unit it can trigger an emergency shut-off. While this is designed to save the unit from mechanical damage, it also cuts off heat to your home. During extremely cold weather, this puts your family in danger. It also increases the chance of burst pipes, which can cause extensive property damage and costly repairs.

It is important to remember your HVAC unit is designed to endure extreme temperatures and withstand the elements. However, snow and ice can build up on our system’s aluminum can or the coil fins. The extra weight could potentially bend those components, causing loud sounds and potentially busting them

Protecting Your Unit from Snow and Ice

Properly protecting your unit from harsh winter elements begins when your unit is installed and continues for the life of the unit. Here are some tips to help keep your system working, even when winter weather rages outside.

  • Make sure your unit isn’t installed directly on the ground. Instead, it should be at least several inches off the ground, high enough to be above normal snowfall. Northern climates may require units to be installed at higher levels than more temperate southern climates.  Most qualified HVAC technicians make sure this happens at installation. 
  • Use shrubs or fencing to create a wind barrier for your outside unit. Just remember to leave enough space for proper airflow and easy unit maintenance. 
  • To avoid a snow drifting and ensure proper airflow even in snowy conditions, your unit should be at least 18 inches from your home’s exterior wall. 
  • During winter weather, be sure to monitor your outdoor HVAC unit. If snow begins to build up around it, it’s time to shovel it away. 
  • Keep your gutters clean. If gutters are clogged, they may drip on your HVAC unit, causing ice to form as temperatures drop. 
  • Never chip away built-up ice. Using a pick or shovel to chip away at ice that has built up on the exterior of your unit could cause damage. Your best option is to let the defrost cycle run its course. You can always call an HVAC service technician if you have serious concerns.

WInter HVAC maintenance is really pretty simple. Just add inspecting your unit to your list of wintertime tasks, along with shoveling your driveway and salting your sidewalk. If you take care of your HVAC unit, it will take care of you, working hard to keep you and your family comfortably warm all winter long.