Is Your Heater Not Working? 8 Common Repairs

When you wake up to a chilly house, it is a startling realization to discover a heater not working! There are a number of reasons that can cause a heater to malfunction.

Sometimes the fix is simple – such as replacing batteries in your thermostat. Other times it could be an important part critical to running your central air and heating system simply wore out at an inopportune time. Lastly, maybe yearly maintenance on your heater slipped your mind. It happens.

What type of furnace or heater do you have?

First of all, do you know what kind of furnace or heater is part of your central air and heating system? Does your heater burn fuel for heat or does it run on electricity?

Along the Texas Gulf Coast, most of the homes here have five types of heater configurations:

  1. A gas-fired furnace that burns natural gas or LP gas (generally propane or butane) which is connected to your central air and heat (Most Common)
  2. Electric heater that is located in your central HVAC system’s air handler (Most Common)
  3. Heat pump combined with an electric heater located in your HVAC system’s air handler
  4. A heat pump operating in heating mode, which operates your AC in reverse. It cools the outdoors while heating the indoors. (Most commonly found with mini-splits)
  5. A dual-fuel heating system (also called hybrid heat) that combines a heat pump and a furnace. This system relies on technology to pick the most efficient way to heat your home.

No matter which type of heater you use indoors, read on to learn about the top reasons that a heater may have cycled off and what repairs we see most often.

Common Heater Repairs For Heater Not Working

Repair calls spike when the temperature dips, which is why we advocate yearly maintenance to avoid many of the most common reasons for unexpected heater breakdowns. These are the heater repairs we see most often after a cold front comes to town.

  1. Heater Power Off

If your heater isn’t working, it can be a good idea to check the power switch.

We sometimes see furnaces switched off by accident when holiday decorations are brought out or put away. It can also happen when another professional is repairing the cable connection, working on the roof, or blowing in insulation.

You can also check your electrical fuse box to see if the power has tripped. A furnace or heater without power is not going to operate. Sometimes the reason could be that one of your furnace’s safety measures is causing the heater to shut down.

  1. Thermostat Malfunctioning

Sometimes the thermostat can be the culprit if your heater has stopped blowing heat. Check that your thermostat has fresh batteries and is set to “heat” or “auto.” If it is set to “cool,” the thermostat will not call for heat.

Sometimes it is possible for the heating or cooling schedule to get switched around on a programmable thermostat by mistake after a power outage. We see that happen sometimes, and it is easy to remedy.

  1. Heater Not Blowing

If your heater is not blowing air at all, make sure to check your air intake vents (return air intake) for blockages.

Any indoor blockage will prevent proper air circulation and can cause your heater to overheat and shut down. Be sure to check for obvious signs that return air intakes are not blocked by furniture or drapes. You’d be surprised how often that happens.

Many central air and heating systems have air filters located in the return air vents. But sometimes there are air filters located in the furnace itself. If that is the case, make sure a dirty air filter isn’t causing the outage.

If you have shut off a number of registers in a few rooms you aren’t using to conserve heat and save on utilities, this can cause enough airflow restriction to make the heater overheat and shut off.

  1. Blocked flue pipe

A licensed HVAC technician will also check the furnace exhaust flue, which is a pipe that vents exhaust from a gas-powered furnace outside the home.

A simple bird or wasp nest wedged in the pipe will cause your heater to shut down. This sort of blockage is nearly impossible to spot from the ground.

  1. Not Warm Enough

If your heater or furnace isn’t keeping your home warm enough, a licensed HVAC technician may also look at your home’s air distribution system or ductwork.

Sometimes sufficient insulation is missing in the attic and your furnace cannot catch up on very cold days.

Other times rodents may have invaded your attic looking for warmth and decided the ductwork and insulation was a good place to make a home. We have seen major damage to ductwork when pests have gotten inside the attic. Raccoons and squirrels seem to do the most damage. Ductwork that has holes in it means that conditioned, warm air would be leaking into the attic instead of being directed to your home’s interior.

Heat Pump Not Heating Enough

If you have a heat pump and it’s not keeping you warm enough, these are the most common reasons:

  • It could be your heat pump doesn’t have the capacity to operate well when the temperature reaches too low. Every heat pump has a low-temperature threshold, though those thresholds are getting lower all the time!
  • If your heat pump is running low on refrigerant, it can’t effectively transfer the cold out of your home.

Electric Heater Not Working and Can’t Keep Up

Keep in mind that on very cold days with very strong winds, an electric heater might not be able to keep up the way a gas-fired furnace can. Heating equipment in the deep south is not sized the way it is for states that are further north. We don’t have enough cold weather conditions that justify that kind of heating. This means that there could be a few days each year where the heater can’t keep up. If it’s a persistent problem, however, ask your HVAC technician at the next maintenance visit for options.

  1. Igniter and Flame Sensor Problems

If your furnace is unable to ignite the flame to burn fuel for warmth, the furnace will shut itself down for safety.

Modern furnaces no longer have the constant pilot lights that many of us might remember from childhood. Instead, modern furnaces use an ignition system that only lights the flame for the furnace when the system calls for heat. If you hear a lot of clicking noises when your heater tries to turn on, that can indicate a problem with your furnace’s igniter.

Related to this is your furnace’s flame sensor, which detects the presence of fire and heat when the heater is on. If it does not detect heat or a flame, it will shut down your furnace for safety.

  1. Cracked or Failed Heat Exchanger

Every furnace has a heat exchanger to separate heated air from the exhaust that is vented out of the home through the flue pipe.

If the heat exchanger is cracked or rusted through, it can no longer do its job and requires immediate replacement. This is not a repair you prioritize for later because it can cause a fire, burn out furnace parts, or vent exhaust, including poisonous carbon monoxide gas, into your home.

Failed heat exchangers on the newer furnaces will often burn up parts before it shuts the furnace down.

  1. Failed Electrical Components Causing Heater Not Working

Blower motors, capacitors, heat strips (electrical heat), PC boards, and other electrical components can unexpectedly malfunction when they have been operating nonstop during a winter storm or extended cold snap.

Both gas-powered furnaces and heaters rely on electrical parts to operate. Many times these issues can be spotted during regular maintenance visits before they become problematic.

Calling a licensed HVAC technician will help you determine if a simple repair will get your furnace back up and running quickly.

Regular Maintenance for Your Heater to Prevent Heater Not Working

Many HVAC professionals advise homeowners to schedule regular maintenance for your heating system at least once a year, often in the fall.

A complete heater inspection and tune-up is how technicians spot small issues before they become big problems. Or worse, before a heater outage catches you by surprise. Regular maintenance is the cure for most heater problems.

Heater Not Working? – Expert Heater Repair in Cinco Ranch & Points Nearby

If your furnace or heater is giving you problems, contact Terry’s A/C & Heating today at 281-495-7830 for expert advice, repair or heater replacement.

Let us know in advance if your heater is not working and if you are looking for a heater tune-up, too. We can complete both services during one service call if we know you’d like both.

We are headquartered in Richmond, Texas, and we serve Fort Bend County and Far West Houston, including the Cinco Ranch, Weston Lakes, and Pecan Grove. Find out what our customers say and what makes our family-owned and operated HVAC business different from the crowd.

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