Why Does My Heater's Air Feel Cold? HVAC Expert Insight

Nov 22, 2021

If your heater is blowing cold air into your home, you’ll likely want to fix it as soon as possible. While the cause behind a heater generating cold air can be as simple as a clogged filter, it could also be a more significant issue, such as holes in your ductwork or a damaged heat pump. Find out more about the main reasons why your heating system could be producing cold air and the ways you can solve them.

5 Reasons Why Your Heating System Is Blowing Cold Air

Before you can fix a heater blowing cold air, you’ll need to figure out what’s causing the issue in the first place. Some of the most common reasons behind this problem include clogged filters, malfunctioning thermostats, damaged heat pumps, blocked drain lines, and cracked ducts. Learn more about how to check for these issues and fix them below:

1. Clogged Filter

Your heating system relies on filters to keep contaminants out of your air and from clogging up your ductwork. When filters are left in an HVAC system for a long time, they can start to trap too many particulates, leading to a clogged filter. If a clogged filter is left too long without being replaced, it can end up causing your furnace to overheat and then blow cold air.

Since clogged filters are a common issue, it’s important to make them one of your first checks if your heater is blowing cool air. You can usually replace a clogged filter with a clean one matching your system’s requirement to solve the issue, making it an easy DIY fix. After changing the filter and waiting a few minutes, check if your heating system is blowing warm air, and if it’s not, you’ll likely need to look for other causes.

2. Malfunctioning or Improperly-Set Thermostat

Another common culprit behind a heating system blowing cold air is a malfunctioning or improperly-set thermostat. When evaluating your thermostat, first check to see if someone in your household hasn’t accidentally switched it to a cool setting. If your thermostat is set on heat and the fan is turned to the “on” or “auto” setting, you can also check to see whether the batteries are dead, replacing them if they are.

While an improperly set thermostat or a dead battery are some of the most common thermostats issues, thermostats can also malfunction for other reasons from time to time. Since the issue could be a more complicated software or hardware problem, it’s best to consult an HVAC professional about performing a thermostat inspection or calibration after you’ve already completed the checks above.

3. Damaged or Frozen Heat Pump

If your heating system runs on a heat pump, you may be receiving cold air due to snow or ice covering the pump. A frozen heat pump is usually easy to fix, as you simply need to remove any ice or snow covering it.

When your heat pump isn’t frozen, you could also have problems with the heat pump malfunctioning due to a damaged metering device, low refrigerant, or broken valves. The needed heater repairs for these issues are fairly complex, so it’s best to turn to an HVAC professional to perform them.

4. Blocked Drain Lines

Many modern furnaces utilize condensate drain lines to remove any water the furnace generates. When these drain lines clog, they’ll often cause a switch to activate that stops the furnace’s burners from lighting. Since the burners need to be lit to produce warm air, your HVAC system could start to blow cold air if your burners can’t light.

Clogged condensate drain lines aren’t something you’ll likely want to fix yourself. As a result, it’s best to hire a heater service technician to inspect the unit to see if the drain lines are really clogged and make any repairs.

5. Holes or Cracks in Ducts

Sometimes, air ducts can start to crack or have holes in them. If these holes or cracks grow large enough, cold winter air from your attic or crawlspace could flow into your ducts and allow hot air to escape. When you allow enough cold air into your ducts, you’ll likely get colder than normal air out of your vents.

A trained HVAC professional can solve this issue by inspecting your ducts and locating any cracks or holes. After they complete their inspection, they can seal the ducts to stop heat from escaping. Besides helping you receive warm air, this repair can help your system operate more efficiently, as it won’t have to overcompensate for all the air it’s losing.

Choose Newcomb and Company for Heater Maintenance and Installation Services in Raleigh

At Newcomb and Company, we regularly provide heater repair and replacement services to homeowners in Raleigh, Wilmington, and the surrounding areas. When you turn to us for heater service, we’ll inspect your unit and identify the root cause of it blowing cold air. After our inspection, we’ll perform the needed repairs. If substantial damage has occurred, we can also perform new heating system installation and replacement services to ensure you stay warm all winter long.

Learn more about our HVAC repair services today. If you’re ready to schedule an appointment or want a free estimate, please contact us.


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