Many homeowners appreciate the efficiency and convenience of having a heat pump. These units provide air conditioning in the summer and warmth in the winter.
However, when outdoor temperatures drop, it is sometimes possible for the heat pump to develop a coating of ice. Is this always a problem? Do heat pumps have the capacity to defrost themselves? When is the right time to be worried about ice on your heat pump?
You’ll find all of the answers to these questions and more below. If you want even more information, then contact Delaware Heating and Cooling. We’re always happy to talk to our customers.
It’s Normal for Heat Pumps to Get Icy in the Winter
If you happen to notice that your heat pump is covered in ice this winter, don’t immediately panic. This could be a totally normal situation that your heat pump is designed to correct.
In fact, it’s expected that the heat pump’s coils might sport a layer of frost in the winter when it’s heating your home. That’s because of the refrigerant turning to gas and then condensing as it comes into contact with the outdoor coil. This condensation easily can freeze in the frigid winter months.
Fortunately, heat pumps are equipped with a defrost function that corrects this problem. The defrost function automatically kicks in when the heat pump detects that certain conditions have been met. The defrost function continues to be a part of the heat pump’s normal winter operations as long as air can be pulled into the machine via the condensing fan motor. If something were to impede this air flow, then the defrost cycle cannot occur, and this can signal the beginning of a larger problem.
The Defrost Cycle in Depth
In places where winter weather gets really cold, like here in Delaware, the defrost cycle is a critical feature on heat pumps. The unit automatically goes through a defrost cycle by reversing the refrigerant flow through the coils.
This reversal means that hot refrigerant is directed toward the frozen outside coils. That hot refrigerant quickly works to melt any ice that has accumulated on the outdoor unit.
Thanks to temperature sensors within the heat pump, the defrost cycle is triggered whenever it is needed and ends once the ice is melted. Because the defrost function does not run continuously, the heat pump is able to operate with maximum energy efficiency.
Each defrost cycle runs for approximately 10 to 15 minutes. Then, normal operation resumes, with the defrost function being triggered again as necessary.
Most of the time, these defrost cycles are all that is needed to keep heat pumps functioning optimally in even the coldest winters.
Is Ice Buildup Ever a Problem?
Usually, the defrost function is all that is needed to keep things running smoothly. However, there may be times when a defrost cycle isn’t enough to keep up with the accumulation of ice.
When too much ice builds up on the heat pump, then it may cause a malfunction or even damage the machine’s mechanical parts.
This means not only that the coils cannot draw cold air out of the home’s interior but also that the unit’s ability to heat will be impaired.
In fact, if you allow the heat pump to try to continue to operate when it is not possible for air to pass through the fins, serious damage can occur. The consequences could include broken fan blades, leaks of refrigerant and the impaired function of outdoor coils.
Calling a certified HVAC technician to inspect the unit is the best course of action when you suspect that your heat pump is completely blocked by ice.
How Do You Know When Ice Buildup Is a Problem?
Remember that a little bit of frost or ice on your heat pump is normal. However, you may be right to be concerned if you see these signs:
- The unit isn’t able to pull air through the fins
- The entirety of the heat pump is encased in ice
- The defrost signal is not triggered even though you can see frost on the coils
- It seems like the heat pump has been frozen over for a long time
- Both the inner coil and the top of the unit are coated in ice
If any of these signs are present or if you just want to make certain that everything is operating as it should, call a trusted, certified HVAC technician.
Reasons Why a Heat Pump May Have an Ice Buildup
Ice buildups are not inevitable in the winter. Typically, the defrost cycle is capable of handling any ordinary frostiness. Nonetheless, certain situations may cause a potentially destructive ice buildup.
These situations may include:
- A stuck reversing valve
- Low levels of refrigerant
- A malfunction with the outdoor blower motor
- The air filter needs to be replaced
- The buildup is blocking the coils or the blower’s fan blades
- A faulty refrigerant metering device, thermostat or temperature sensor
Most of these situations cannot be handled by the average homeowner. It’s always a good idea to ask for a service call by an experienced heat pump technician.
Steps to Take If You Think You’re Heat Pump Isn’t Defrosting
You’ve looked at your heat pump and discovered that much of it is covered in ice. Are there things that you can check or things that you can do that might rectify the situation?
There could be. For instance, take a good look at the air filter. Is it clogged with buildup? If so, then the problem may be corrected simply by replacing the filter.
It also might be a good idea to take a look at the condensing fan’s fins. Are there any leaves or other debris in there that might be affecting normal functioning? If so, clear them away to see if this corrects the problem.
Take a good look at the gutters, if any, that are directly above your heat pump. Gutters that are overflowing drip excess water onto the heat pump, and this can contribute to freezing. Make certain that gutters are clear and well secured to the roof to prevent this from becoming an issue.
It further may not hurt to check that the ground on which the outdoor unit sits is still level. Uneven ground can impede the drainage path for any ice that the defrost cycle is melting. It also can block air flow, which only contributes to the buildup of ice.
Move indoors to manually turn on the fan at the thermostat. If you don’t start to notice output from the vents within a few minutes, then there may be an issue with the blower motor. This almost always necessitates a call to an HVAC tech.
Schedule Maintenance and Inspection with Delaware Heating and Cooling
Now is the ideal time to request an annual maintenance and inspection visit from a Delaware Heating and Cooling technician. Regular maintenance and inspection ensure that your heat pump is optimally functioning before the seriously cold weather arrives.
Typically, this is enough to ensure that you won’t see excessive and potentially damaging ice buildup on your heat pump this winter. If this issue does crop up, then give Delaware Heating and Cooling a call. Our friendly, local and knowledgeable technicians are always available to ensure that your home is warm and toasty in the depths of winter.
When the weather gets cold and threatening, it’s best to be prepared. Take preventative steps by having maintenance performed and keep Delaware Heating and Cooling’s contact information handy for the icy months.