How To Fix Heat Pump Freezing Up

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Change The Air Filter

Heat Pump Freezing Up Blower Motor Cutting Out & Other Problems

Air filters are meant to ensure that dust and other impurities do not get into your AC unit. They work by trapping the dust and ensuring your airflow doesn’t become blocked.

Dirty air filters that are clogged won’t allow air to pass through them efficiently, and as a result, you will need to replace them. They do a pretty good job of keeping you healthy as well.

The primary reason it is advisable to replace an air filter instead of cleaning them is that cleaning filters can be sophisticated. Some types of dirt cannot be removed with cleaning, no matter how well you clean the air filter.

While changing the filters on your Air Conditioner, you should ensure that the replacement filters you get are compatible with your unit. The importance of this is that there are filters of different sizes and designed in different ways.

Take your old air filter with you when you go to buy a new one. Call us at Air and Energy for free advice on choosing the right air filters for your AC, and we can even order you a replacement and change it as well.

Protect Your Heat Pump From Ice And Snow

To protect your unit from ice and snow, you must:

Build A Wind Barrier

Plant shrubs or other perennial plants around your system. Place them 24 inches away from the heat pump as it needs plenty of space to maintain adequate airflow.

You may also opt for a privacy screen its easy to install and best for concealing a heat pump. However, it is expensive. Also, never cover the unit.

Because your heat pump gets used throughout the year, covering it makes it a fire hazard.

Check Gutters Periodically

Broken or clogged gutters result in constant water leaks onto the outdoor unit, causing ice build-up. Inspect them from time to time to make sure they are working normally.

Signs Of A Problem With An Hvac System

To help you identify when there is a problem with your HVAC system throughout the cycle of seasons, here is a list of common signs of problems with your heat pump:

  • A heavy amount of ice covers your HVAC unit
  • Condenser coils have heavy ice build-up
  • The heat pump evaporator coil is freezing up
  • Your heat pump does not effectively heat your home
  • Strange noises from the heat pump
  • The heat pump unit does not pull or release any air

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What To Do If You Got A Frozen Heat Pump

Your heat pump is frozen. Now what?

If your heat pump is frozen and you’re freaking out, don’t worry it is not a big deal! It happens in the wintertime to all of them sometimes- we know because we live in this town too. There’s usually nothing wrong with it, so don’t be scared or anything!

Heat pumps can freeze up in cold weather, and it’s critical to know what to do if this happens. In this blog post, we’ll explain why your heat pump might freeze in the winter and what you can do about it. We’ll also discuss the defrost function on heat pumps and when a frozen heat pump is a problem. By following the tips in this blog post, you can keep your heat pump running smoothly all winter long!

And if you run into a frozen heat pump during the summer, check out what to do here!

Defrost Your Heat Pump With An HVAC Pro

Heat Pump Not Turning On Or Off

What Causes a Heat Pump to Freeze Up?

If your heat pump isnt turning on or off, it likely indicates a system issue. Your thermostat controls your heat pump, so if the heat pump isnt turning on or off it could be because your thermostat isnt able to relay that message to the heat pump. Alternatively, a power loss, or electrical problem could be causing the issue.

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What If The Defrost Cycle Isn’t Working

When the defrost cycle isnt working, there are more than a few reasons this happens.

1. Clogged Air Filters

These prevent the warm air from reaching the coil, so the defrost function wont work. Check if the air filter has a build-up and replace it if needed.

2. Defective Reverse Valve

This controls the systems ability to switch to defrost mode. So, if it gets damaged, the unit wont defrost.

3. Broken Outdoor Fan

When this breaks, it impedes the release of hot air, which causes frost to accumulate.

4. Low Refrigerant

When this happens, it reduces the amount of heat that the defrost function produces, making it ineffective.

5. Leaking Gutter

Water leaks trigger the defrost mode when it is unnecessary. And that can lead to a malfunction.

What Causes A Heat Pump Freeze

Quite a few situations can lead to a freeze of your unit, coil, or fan, including:

  • Defrosting failure. A properly operating heat pump will occasionally go into a defrost mode to clear the coils of frost and ice. This process usually kicks in by way of a timer or sensor, and defrosting takes roughly a few minutes. If this system fails to operate then your heat pump will continue to ice up until failure
  • Restricted airflow. Leaves, plant matter, debris, and even snow can build up to the point of clogging your heat pump, eventually leading to a freeze-up. The clog can occur at the outdoor unit, invents, or at the filter for your system.
  • Introduction to freezing water. An odd and elusive cause can be your roof or gutters if something has gone amiss up top. Leaking gutters or poorly diverted water from the roof can drip down to the pump, introducing large amounts of water that will freeze rapidly.
  • Disrepair. Things normally handled by regular maintenance can cause freezes including Inadequate or excessive refrigerant, a failing blower motor, or faulty sensors.

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How To Stop A Heat Pump From Freezing Up Steps

  • Check for leaking gutters above the heat pump. Overflowing water can keep the external coil so wet that it freezes over.
  • If overflowing gutters appear to be the problem, clean or repair them.
  • Make sure that a 3-foot diameter of clear space surrounds the outdoor condenser.
  • Leaves, deep snow, thick shrubberies, or other blockages need to be removed.
  • Rake, shovel, or sweep away debris as necessary to clear the area.
  • If youve had cold weather but only light snow, still check for snow blockages. Strong winds could push powdery snow inside the unit and clog it up.
  • Inspect the outdoor unit to see if it has sunk or become flooded. Shifting ground, deep puddles, or heavy snow melt can flood the unit.
  • Dig a drainage channel to stop water from pooling around it.
  • Contact a heat pump repair company like Oliver to reposition a condenser that has shifted.
  • Learning how to stop a heat pump from freezing up could come down to changing the air filter. A dirty, badly clogged filter brings airflow to a crawl.
  • Find the air filter in your return air duct or air handler. You might need a screwdriver to open the duct cover.
  • Remove the old one and install a new one of the appropriate size.
  • If you have a filter that requires cleaning set a schedule to clean as needed per manufacturer recommendations.
  • A mechanical failure, especially with the defrosting mechanism, is frequently the cause of a freeze up.
  • A heat pump inspection from Oliver will reveal if you need a new part or thorough cleaning.
  • What To Do If The Heat Pump Isnt Defrosting

    Why is my heat pump freezing up?

    If your heat pump is blocked by ice or doesnt seem to be defrosting enough to allow it to run normally, there are a few things you can check. Make sure that the air filter is in good condition. Replace the filter if it seems to be full of buildup. Next, inspect the fins of the condensing fan. Be sure to clear away any leaves or debris that may be blocking regular function. Then, set turn on the fan manually at the thermostat. If no air output comes through the vents, it could indicate a problem with the blower motor. Finally, call your trusted heating repair company to report your findings and request assistance.

    Find more information in our related posts about How Snow Can Impact Your Furnace and HVAC and 10 Ways to Winterize Your Home.

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    What Does It Mean When A Heat Pump Freezes Up

    If theres a thin layer of frost over the coils of a heat pump, thats not cause for alarm light frost is normal. What were talking about is a complete icing-over of the coils or the unit, preventing it from operating. In extreme cases, the whole outdoor unit might be encased in a block of ice, collapsing the coils and potentially ruining the entire system. A few common causes can include:

    • Rather than starting on its own timer, the heat pump defrost cycle is not working
    • Restricted airflow at the filter, vents, or around the outdoor unit itself
    • Infiltration of water from a gutter or the roof, which then freezes
    • A poorly-maintained unit, possibly with an undercharge or excess charge of refrigerant in the system.

    Understand The Common Causes Of Frozen Heat Pumps

    Knowledge is key if you hope to prevent your heat pump from freezing during a freak winter ice storm. The most common cause, obviously, is chilly temperatures. When the temperature dips closer to freezing, you may notice ice accumulating on the coils or refrigerant lines. Depending on your heat pump model, it may offer a defrost cycle that can combat brief freezing periods.

    Low refrigerant levels are another common cause of freezing. Heat pumps are more susceptible to ice when refrigerant levels are low. Calling in an HVAC professional to inspect your heat pump prior to winter is a good option, as any HVAC technician will ensure the pump has plenty of the required refrigerant.

    Improper installation is another culprit. When a heat pump is installed improperly, airflow can become blocked, causing the appliance to freeze. This is why its crucial to hire a licensed and experienced HVAC professional for all of your heating and cooling needs.

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    Low Volume Of Cold Air

    One of the problems that usually happen with heat pumps in summer is that the air isnt very cold, and it takes the heat pump a long time to cool a room. Some of the reasons are the low air pressure or low volume of cold air through the vents.

    Check the airflow in the vents. If there is no airflow, check the air handler. If there is not enough air blowing out of the vents, check your air filter. The air filter needs to be cleaned if dirty or replaced.

    Heat pumps perform less efficiently from lack of airflow. Clogged components, particularly the coils and the air filter, can restrict airflow. Check these parts first once youre sure that the thermostat and the electricity are alright. The air might not cool and get through properly if your coils and filters are clogged with dirt and debris. You may also want to check your condenser and fins as well.

    You can fix this by cleaning them. For the outdoor coils, clean them by gently hosing them down with water. Dont use pressure wash as it may damage the coils. You can use rags or soft brushes for parts that are hard to reach. For air filters, you can either clean or replace them, depending on specifications.

    For example, fiberglass filters should be replaced every month, while electrostatic filters can be washed every 3 months. Regardless, make sure to check your heat pump every month.

    Frozen Heat Pump Heres Why And How To Fix It

    How to Fix an Ice

    A service call comes in- the coils on the heat pump are frosted over and the unit isnt working very effectively. This is a scenario youre going to run into time and again as an HVAC tech, and there are several reasons why it might occur. Some of those reasons are pretty straightforward and direct, while others are going to take some heat pump troubleshooting and critical thinking.

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    Your Heat Pumps Defrost Cycle

    All heat pumps, regardless of the age, have a built-in defrost cycle. This is thesystems method for defrosting a heat pump. The older units have a mechanical timer that triggers the cycle, while newer units are controlled by a solid state control module and temperature sensors. Either way, the system itself works the same.

    A well-running heat pump should run in defrost mode at timed intervals and can run from 30 seconds to a few minutes. The defrost cycle helps rid the outdoor unit of frost and ice buildup to prevent the system from freezing over.

    The entire system is reversed as the air conditioning is turned on, which causes the refrigerant to heat up and run through the outdoor coil to melt ice. The outdoor fan is stopped to prevent it from cooling the outside coil. The defrost will continue until the temperature of the outside coil reaches about 57 degrees.

    During the heat pumps defrost cycle, the indoor fan continues to run, and your system is in cooling mode. In order to avoid cold air from circulating throughout the house, a backup heating system can be utilized when the pump goes into defrost mode.

    Heat Pump Is Not Running

    After checking your thermostat that is working fine, check your outdoor unit next. Never dismiss the possibility that the heat pumps fan might have stopped running. You can do the following for this situation:

    • Check your circuit breakers or fuses if your unit isnt running while switched on. The system runs on 220/240 Volts, and both indoor and outdoor units breakers have to be checked. Also, there might not be power delivered to the unit at all.
    • Make sure to check the wiring between the outdoor unit and the thermostat, so there is communication. Many needed repairs to HVAC units happen due to faulty or loose wiring.
    • If the unit seems to be fine, check if your outdoor unit has a reset button and press it. It might fix the problem.

    However, if none of these tips seem to be working, something else might need fixing. In this case, its best to call the local technician.

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    Clean Your Evaporator Coil

    You can also prevent your AC from freezing by cleaning the evaporator coil. The importance of this is that when impurities such as dust accumulate around the coil, they reduce their effectiveness. To remove the dust and other foreign things that might be on the coil, you should clean it regularly.

    Since evap coils are delicate creatures that require special tooling, we recommend you call an HVAC professional. The best prevention is to schedule preventative maintenance with your local friendly HVAC company such as Air and Energy.

    We can check and clean your Evap coils during a seasonal tune-up to ensure your evap coils work perfectly the next time you fire up your AC.

    Heat Pump Making Unusual Noises


    If you hear strange noises coming from your heat pump, its likely a sign theres a problem. These strange, not normal noises include, but arent limited to, banging, screeching, rattling, buzzing, grinding, or gurgling. If you hear any of these sounds, extremely loud sounds, or prolonged sounds coming from your heat pump, it could be a sign of electrical issues or system failure.

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    Nd Step: Switch Your Thermostat Fan To On

    • Turning the HVAC fan to ON will force it to blow warm air over any frozen coilswhich will speed up the defrost process. Make sure its actually set to ON and not to AUTO. Automatic settings cause the fan to cyclestarting and stopping over and over again. You want continuous, non-stop airflow over the frozen areas. There is an option on your indoor thermostat to do this.

    Solutions To Your Heat Pump Freeze Up Problem

    So despite all the your best efforts and preventative measures, your heat pump still freezes up. What do you do now? Dont panic, this is a normal issue with heat pump systems and there are solutions. Weve listed out the best solutions below.

    #1 Solution: Give the System Some Time

    Your heat pumps defrosting system, especially if its a newer system, likely has no issues and is working hard right now to get your system thawed and running again. Sometimes it can just take some time for the defrost system to do its work, which can make it seem like theres a problem where there isnt none. The best advice we can give you is to have some patience. If your heat pump doesnt seem to be running, just give it 3-4 hours to defrost itself. This will almost always solve the issue and your system will kick back in and continue heating without any noticeable temperature drop within your home.

    What to Do If Your Heat Pump Doesnt Defrost Itself

    If youve given your heat pump at least 4 hours to defrost itself, and it is still not operating normally, your best bet is to give us a call and schedule service from one of our HVAC technicians. Additionally, scheduling regular HVAC service can help you avoid common issues like this that cause your heat pump to freeze up, and keep your system running smoothly year round.

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    Dealing With A Heat Pump That Has Shut Down Due To Freezing Temperatures

    Heat pumps typically freeze in cold weather, particularly if the area where you live has high humidity. This can occur even if the outdoor temperature is above freezing. Because the outdoor coil on your heat pump is typically 10 to 20 degrees colder than the outdoor air, if it is a 39 degree day the outdoor coil may be as cold as 24 degrees. If on that same day the dew point is as high as 33 degrees then moisture will have no option but to condense on the surface of the coil. Since it freezes at 32 and the coil is at 24, the moisture turns immediately into frost.

    It is perfectly normal to have light frost on a heat pump, but if the system is encased in ice or doesnt defrost itself within 3-4 hours, something could be wrong with the defrost functionality. This is especially a risk during cold or freezing rain, as well as snow. If your heat pump doesnt seem to be defrosting properly, you will need to to thaw and maintenance the heat pump without delay. In many cases however, getting your heat pump running smoothly again after a freeze up is something you can handle easily on your own.

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