No one wants to turn on their HVAC system in winter only to receive a blast of cold air. However, a malfunctioning heat pump might not provide the warmth promised in its name. Upon searching “why is my heat pump blowing cold air,” you may find all sorts of answers.
Learn from the experts at Leith Heating & Cooling, a top provider of Elgin’s heat pump services. Here, we answer questions regarding how heat pumps work, ways to troubleshoot them, and when to call a professional. For more details or emergency services in Elgin, IL, call us anytime at 847-851-8698.
Q1. Why Are These Systems Called Heat Pumps?
These systems received their name due to how they alter air temperatures. Heat pump systems provide heating and cooling, consisting of an outdoor unit and an indoor air handler. Like ACs, they have coils and fans that help change the temperature of the air and move it through the system.
The system either pumps heat inside or outside. During the summer, the pump absorbs heat from the indoor air and releases it to the outside. In winter months, it switches to heating mode, absorbing heat from the outside and moving it inward.
Q2. How Do Heat Pumps Work?
Knowing how these systems function can help you troubleshoot their problems. In this case, the indoor and outdoor units each have a single coil and a fan. The coils switch between being an evaporator or condenser, depending on the setting.
In heating mode, it transfers heat from the outside to the inside. In cooling mode, it instead pushes heat outside from the inside. The fans provide airflow, allowing the heat to travel between the coils and the air.
The coils use refrigerant, which easily transfers heat energy and changes between gas and liquid forms. Something cold has very little heat energy and absorbs it from its surroundings to reach equilibrium. Refrigerants use this principle to absorb heat, traveling through the coils to transport the energy.
Let’s use an air-source heat pump during the summer as an example:
- A suction line, the low-pressure side, takes in the refrigerant.
- Refrigerant enters the compressor in a gaseous form, pressurizing it and pushing it through the system. The pressure gives the gas heat energy, making it hot.
- A discharge line transports the superheated gas from the compressor to the condenser coil.
- Upon entering the condenser, a fan blows indoor air over the coil and sends it outside. The air, which has a lower temperature than the coils, absorbs heat and carries it as it leaves. The gas turns into a warm liquid due to the temperature change.
- The liquid enters the liquid line, reaching the expansion valve and evaporator coil.
- The expansion valve has high-pressure and low-pressure sides. As the liquid expands on the low-pressure side, it becomes partially gaseous again, but this time, it lacks heat energy. The refrigerant becomes frigid.
- The partially gaseous and liquid refrigerant goes into the evaporator coil, and vents suck indoor air over them. Because the refrigerant is cold, it absorbs the heat from the indoor air to become fully gas. The indoor air, now lacking heat energy, becomes cold and reenters the property through the air ducts.
- The refrigerant returns to the compressor to start the cycle again.
This process explains how ACs work as well. However, heat pumps have a reversing valve, which switches the coil functions and the direction of the refrigerant. With the reversed direction, the place the heat goes also changes.
Q3. What Can Cause a Heat Pump To Malfunction?
A heat pump malfunction might prompt you to search, “why is my heat pump blowing cold air?” While many issues can cause system hiccups, the source of the problem tends to be one of these three:
- Your heat pump blows air that feels cold compared to your body temperature but meets heating requirements.
- The heat pump’s defrost mode causes cold air to blow into your home.
- Your system has a technical issue that requires a professional contractor to fix.
We will detail these potential causes and help you troubleshoot your heat pump. Hopefully, the issue will be one of the first two. However, feel free to call us at 847-851-8698 if you have a technical issue we need to solve.
It’s Just Really Cold Outside
Because a pump transfers heat from the outside during winter, it may have trouble increasing the air temperature. Frigid temperatures mean the system must work harder to collect heat than when it’s cool or cold. Air-source heat pumps have this problem more often compared to ground-source heat pumps.
Regardless, the heat pump still provides air that heats the property. Instead of air that feels hot, however, it may be cooler than a body temperature at roughly 98°F.
For example, a heat pump may try to collect outdoor heat from frigid conditions but only warm the incoming air to 85°F. This air will feel cooler but will still increase the indoor temperature. Additionally, heat pumps can switch to backup heat if they cannot collect enough from outdoors.
You can try checking your indoor temperature, then checking again after about thirty minutes. If the rooms get warmer, the heat pump is likely functioning as it should, but the air feels cool. You should check if it is in defrost mode if it doesn’t warm up.
The Heat Pump Is Defrosting
Heat pumps will blow cold air into the property as it defrosts. Outdoor coils have a temperature sensor that alerts when the unit temperature decreases to 31°F. A timer in the unit counts off, usually taking 30, 60, or 90 minutes to finish.
If the unit’s internal temperature still sits at or below 31°F, the system starts its defrost mode. The defrost cycle runs even without any ice on the pump since the sensor only detects temperature and not moisture. If the system has no frost to melt, it will blow cold air into the home.
You can check if your pump is in defrost mode by going outside and looking at the unit. Steam might come from your outdoor unit, but the fan won’t be turning.
Genuine Heat Pump Malfunction
When neither of the other conditions exists, you likely have an internal problem that requires contractor assistance. A few reasons you may need to call us may include the following:
- Refrigerant leaks
- Frozen units
- Broken reverse valves
- Blockage within the unit
- Outdoor airflow obstructions
- Thermostat glitches
- Consistent maintenance needs
While you could resolve some issues on your own, like the thermostat, you require assistance with others. For example, you must have a licensed HVAC technician repair refrigerant leaks because of the U.S. Environmental Protection Agency. Attempting to DIY is against the law and could put you at serious risk because refrigerant has hazardous properties.
Call Us for Your Heat Pump Repairs
Leith Heating & Cooling technicians ensure that citizens in Elgin, IL, and surrounding areas have a reliable HVAC system. We know how important your heat pump is to facilitate a comfortable living space in the coldest conditions. Our team provides free quotes, efficient repairs and replacements, and top-quality customer service.
While searching “why is my heat pump blowing cold air,” call on our team to restore comfort in your home. You don’t have to wait until business hours to receive your heat pump repair service. Our call system accepts assignments 24/7 to take care of you in emergencies.
For more information about our services, visit our contact page or call 847.851.8698 today.