How to deal with frozen heat pump during winter

Though a heat pump can freeze during summer, you are more likely to experience a frozen heat pump during winter frequently. This kind of problem often happens with HVAC units. This can be very frustrating to deal with because you need your heating system more during winter. In this article, you’ll learn how to deal with frozen heat pumps during winter.

First, let’s understand what can cause your heat pump to freeze. Meanwhile, if you’re looking for high-quality pneumatic products and want to employ advanced direct-operated valve technology, make sure to buy humphrey products.

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What is a Heat Pump?

A heat pump, typically in the backyard or another exterior space, is a component of your home’s heating and cooling system. It can provide warmth and cool your home, much like a central air conditioner would, but it also can cool your home. During the months when the temperature outside is lower, a heat pump will extract heat from the cold air outside and transfer it within. 

During the months when the temperature outside is higher, the heat pump will extract heat from the air inside and use it to cool your home. They give comfort throughout the year by being fueled by electricity and transferring heat using refrigerant in an air conditioning system. Since they are also capable of providing heating, homeowners may not require the installation of additional systems to keep their homes at a comfortable temperature. 

The capabilities of the indoor fan coil can be expanded by the installation of an electric heat strip if it is installed in a location that experiences cooler temperatures. Heat pumps, in contrast to furnaces, do not require the use of fossil fuel to function, making them a more environmentally friendly option.

What Are the Different Kinds of Heat Pumps?

The air-source and ground-source heat pumps are the two varieties of heat pumps that are used most frequently. Air-source heat pumps are becoming increasingly common for use in domestic heating and cooling systems because of their ability to transfer heat between indoor air and outside air. Heat is transferred from the air within your home to the earth outside using a device called a ground-source heat pump, which is also referred to as a geothermal heat pump. 

Because the ground temperature remains relatively constant throughout the year, these need a higher initial investment, but they are often more effective and have a lower cost of operation than alternative systems.

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How Does a Heat Pump Function?

Heat pumps are devices that move heat from one location to another using a variety of air or other heat sources. A heat pump has two components: an outdoor condenser and an internal air handler. This configuration is known as a split system. The refrigeration is circulated throughout the building using an external heat pump condensing unit, much like a central air conditioning unit. 

A chemical molecule that can absorb heat and make heat transmission possible is known as a refrigerant. A reversing valve allows a heat pump to switch the direction in that refrigerant flows through the system. Because of this, it can do two things for you: in the summer, it can keep your home cool, and in the winter, it can warm it up. 

When the heating mode is engaged, the refrigerant in the outdoor condenser draws the heat from the surrounding air and stores it. In the next step, the compressor uses heat and pressure to transform the liquid refrigerant into a vapor or gas. After that, the compressor forces the refrigerant into the air handler unit found inside the building. 

The vaporized refrigerant travels to the indoor unit coil while it is still contained within the air handler. The warm air from within your home is drawn over the coil, where it then takes on the temperature of the hot refrigerant. When heat is removed from the refrigerant, it changes back into a liquid state and is sent to the outdoor unit to continue the cooling process.

Snow or frost build-up on the unit

The primary cause of a frozen heat pump in the winter is snow or frost. During this weather, it is natural for snow and frost to gather everywhere. Similarly, they can accumulate on the unit and cause it to freeze. You need to be careful when you attempt to remove the snow. You cannot do that with a sharp object unless you are ready to risk damaging some part of the heat pump. You can melt the snow or frost with water.

Dirty or clogged coils

Another major cause of a frozen heat pump is a clogged coil. Heat pumps come with two coils. During winter, things like snow, debris, and dirt can easily accumulate and choke the coils. This will subsequently prevent air from flowing adequately through the system. The effect of this is that the defrost cycle may not impact the frozen heat pump in any way.

To fix this, you will need to unclog the coil by cleaning it. Clear out any dirt in the environment that can likely tamper with the efficiency of this system.

Water dripping on the unit

Whenever water drips on the unit during winter, it is usually in the form of freezing rain. Once the dripping water gathers on the unit and it’s not cleaned off, it will eventually freeze up and result in a frozen heat pump.

Placing your heat pump unit where the rain cannot touch it will prevent this problem. However, suppose you have already installed the unit, ensure that you clean the dripping water before it gathers on the unit.

Water from the ground

It is possible that you have a frozen heat pump because the unit sank into the ground. This means that freezing rain is not the only cause of frozen heat pumps, water from the ground is also enough to cause this problem. You will need to increase the distance between the ground and your unit using a concrete slab. This will ensure that the unit does not get sunk into the ground again.

How to deal with a frozen heat pump during winter

Exploit the defrost cycle

Let the heat pump enter the defrost cycle. This will be more effective if the unit is covered with a thin layer of snow. However, if there is a lot of snow, the unit’s defrosting cycle may not be helpful.

What is a defrost cycle?

A heat pump has three cycles: the heating cycle, the cooling cycle, and the defrost cycle. The first two are responsible for keeping the temperature high when needed and cooling the system when required. However, our focus here is the defrost cycle.

The defrost cycle is responsible for keeping the heat pump from freezing up. Here is how it works.

Your heat pump is designed with a sensor that passes across to the system that the outside temperature is lower than 30 degrees Fahrenheit. Once the system detects this development, it automatically goes into defrost cycle.

This is affected by the reversal of the valve, which then allows the refrigerant to run backwards. This immediately extracts heat released to the inside and delivers the heat to the outdoor coil, which melts the ice and defrosts the system. This is put in place to ensure that you do not have to worry about defrosting your heat pump. But, it is not always enough.

It’s easy to know when your heat pump automatically goes into defrost cycle because the indoor heat is stopped temporarily. However, this does not mean the inside becomes cold immediately. Your heat pump also comes with a supplement system that keeps the indoor temperature stable for the time being. Another way to know that your heat pump is on defrost cycle is that the indoor and outdoor fans also stop working, leaving only the compressor operating. Defrosting can last for up to 10 minutes.

The fact that the built-in defrost cycle is not always enough to deal with a frozen heat pump during winter is why you need this article. Not solving the problem of a frozen heat pump can cause it to keep jumping into the defrost cycle, and this can cause damage to the system.

Call a technician

After trying the defrost cycle, and you’ve also tried removing the debris and dirt, but you’re unable to find the cause of the frozen heat pump, it is advisable to enlist the services of a technician from a trusted company like the ones from this site to help you look into it and get it fixed. You shouldn’t keep checking the unit yourself as this can cause you to tamper with some parts of the heat pump, which could lead to even bigger problems.

Other Methods on How to Deal with a Frozen Heat Pump

Allow Time for Your Heat Pump System to Work

Your heat pump’s defrosting system probably has no problems and is probably working hard at the moment to get your system defrosting and functioning again. This is especially likely if your heat pump is a more recent system. Sometimes the defrost system merely needs some time to perform its job, which can give the impression that there is a problem when there isn’t any issue at all. 

The most helpful piece of advice is to exercise some patience. Give your heat pump three to four hours to thaw on its own if it appears that it is not functioning properly. This will usually always remedy the problem, and your heating system will start up again and continue to heat your home without there being any discernible dip in temperature there.

Start the Fan

Turning on the fan is one of the things you may do to see if it helps defrost your heat pump, provided that it is equipped in your system. In most cases, the defrosting process only takes about an hour when air is blown on the frozen apparatus. You may use the fan in exhaust mode if the air temperature outside is especially chilly. It’s possible that turning on the fan for a while won’t solve all your problems, especially those involving freezing, but it’s a quick fix you can try.

Adjust the Temperature Sensor

Moving the temperature sensor that is attached to the exterior of the heat pump unit is yet another method that you can test out on your own. When frost conditions arise, your heat pump will need to operate for a longer period to melt the ice. It is possible for the defrost cycle to not be activated for the appropriate amount of time if the sensor is exposed to direct sunlight or if it is otherwise warmer than the remainder of the device. 

The issue can be remedied to some degree by performing periodic adjustments to the thermostat that is located on the exterior of the device. If you want to go with this alternative, make sure that you record the location of the sensor’s starting point so that you may successfully replace it. 

However, this option shouldn’t be pursued till all other options have been exhausted. If none of the other possibilities have worked, it is probably best to bring in one of our technicians at this time, unless you are confident in your ability to handle the situation on your own. If the sensor is moved to an incorrect location, it is possible that the defrosting process may be halted, which is the exact reverse of the result that is sought. If you are undecided about whether or not to take this step, the best thing for you to do is get in touch with our staff so that we can examine your system.

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While fixing your frozen heat pump yourself is possible, periodic maintenance is still advised. This is to save you the unpleasantness of having to endure a cold day while waiting for the technician to fix your heat pump if it develops a major problem. Also, maintenance is cheaper and more efficient than waiting for a problem to develop before calling a technician.