FROZEN HVAC: SHOULD YOU WORRY ABOUT A FROZEN OUTDOOR HVAC UNIT?




Heat pumps (which draw in heat from outside to heat homes, and vice-versa) have an outdoor unit with an important fan and coils. If your winter gets a bit snowy or icy, you may be worrying about how this frozen HVAC unit can function. Here are a couple of useful questions you can:

  • How cold is it? Usually, temperatures need to be well below freezing to impact the outdoor unit. Heat pumps have a "defrost cycle" that kicks in periodically and gives the frozen HVAC unit a break while thawing it out. Heat pumps tend to build up frost naturally, so they are used to thawing out after a minor freeze. However, if temperatures drop into the teens and stays there, pay close attention.
  • How thick is the snow layer? A couple inches isn't much to worry about. Usually, the pump can use its defrost cycle to solve any problems, and a couple inches isn't going to stop the fan or freeze the coils. But if you have a couple feet, you should think about pushing the snow off – and building barriers so that blizzards can't slam all that snow into the pump.
  • Is the heat pump making any strange noises? A bit of rattling is common when switching to defrost mode. But if your outdoor unit is clunking away, groaning like it can't move, or making other strange noises, it's time to take a look. This is a sign that ice may have built up and caused some problems that could damage your system.
  • Is the defrost mode working? You can usually tell! When your unit stops and reverses, take a look outside. Rising steam is a good sign the defrost is on. You should also be able to see the fan moving. If you don't see either of these signs, the pump could be malfunctioning.
  • Are there thick sheets of ice on the unit? Ultimately your big concern is ice so thick the pump can't move or draw on any outside air. If thick ice is layering the entire unit (freezing rain or a melt/freeze cycle), ask a professional what to do.

If you're worried about frozen HVAC units in winter conditions, give Ragsdale a call and explain what's going on. We can suggest solutions and pay a professional visit to make sure there's nothing to worry about!

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