Woman controls thermostat while man with suitcase prepares to leave home

Residents of Denton County, Texas, understand how vital an HVAC system is for comfort and safety. Weather.gov notes that from 1991 to 2020, Denton County averaged a high of over 80 degrees Fahrenheit for five months out of the year and an average of under 40 degrees Fahrenheit three months out of the year. But keeping cool in the hot months isn’t only a matter of comfort. In 2023, Denton County saw 255 heat-related illness cases and, tragically, three deaths. 

Here, Sanger-based Cote’s Mechanical will provide HVAC tips for Denton County residents on how to stay comfortable indoors year-round.

Importance of HVAC Maintenance in Denton County

A Technician tests a floor vent in a home

Regardless of where you live, air conditioning maintenance is essential. It is especially important in places like Denton County, where air conditioning often sees heavy use and high temperatures are common. 

The following are just a few of the possible benefits offered by routine HVAC system maintenance for your Denton County home:

  • Save money on energy bills.
  • Increase air quality inside your home.
  • Help prevent unexpected HVAC breakdowns.
  • Save money on repairs.
  • Maintain good HVAC performance.
  • Prolong HVAC system life.
  • Better for the environment.

Energy-Efficient HVAC Practices for Denton County Homes

While HVAC systems make hot and cold weather more bearable, no one wants to deal with high energy bills. According to Energy.gov, heating and cooling account for about half a typical home’s energy usage. The following are several energy-efficient practices that can help you save money on your heating and cooling costs throughout the year.

Routinely Change or Clean your Air Filter

Inspect your air filter once a month. An air filter inspection is essential during the summer and winter when your HVAC system is most used. If your filter appears dirty, change it (or clean it if you have a washable HVAC air filter). At the very least, you’ll want to change or clean your HVAC air filter every three months. Please note that how frequently you should clean or change your air filter depends on variables such as the type of air filter you have and how much you use your HVAC system. Dirty HVAC air filters waste energy, can damage the HVAC system, and even cause the HVAC system to fail early.

Have an Energy Star Smart Thermostat Installed

Smart thermostats are convenient because they allow you to control your home’s temperature from a smart device and also help you save energy. A smart thermostat can adjust the temperature in your home to suit your preferences. An energy-star certification means that the smart thermostat has been tested and will provide energy savings. 

Have Heating and Cooling Ducts Sealed and Insulated

The ducts that move air between central air conditioners, heat pumps, and forced-air furnaces are often a significant source of energy loss. To increase your HVAC system’s efficiency, have an HVAC professional seal and insulate the ducts. 

Seasonal HVAC Tips To Beat the Weather in Denton County

Some HVAC work should also be conducted seasonally, along with regular HVAC maintenance. The following are a few seasonal maintenance tips for your HVAC system. Every situation is different, and some maintenance may need to be performed more frequently.

Tips for Spring HVAC Maintenance

  • Have your air conditioning system cleaned and inspected by a reputable HVAC professional.
  • Clear vegetation and weeds from around the outdoor air conditioning unit.

Tips for Fall HVAC Maintenance

  • Remove brush, leaves, and twigs from around the outside central air conditioner unit.
  • Have an HVAC professional inspect your furnace and ductwork.

Expert Advice on HVAC Troubleshooting and Repair in Denton County

A technician looks at the thermostat in a Lewisville home

Even with regular maintenance, HVAC systems can experience problems. The following is a guide for troubleshooting and repairing common HVAC system issues. Given the risk involved, it is vital that you do not try to fix anything you aren’t familiar with—it pays to play it safe and contact an HVAC professional if you don’t understand something.

The HVAC System Doesn’t Turn On

One of the most frequent HVAC problems is an HVAC system that does not turn on. There are several potential causes, ranging from simple to complicated.

How To Fix It

  • Start by checking the thermostat’s batteries.
  • Check to see if the circuit breaker is tripped. At the circuit breaker, look to see if the HVAC system’s breaker is set to “OFF.” If it is, you can switch it to “ON”. Caution: Stand to the side of the breaker box, not directly in front of it.
  • If neither of the above works, contact an HVAC professional.

Caution: When dealing with electrical trouble, you must contact a professional, as a house fire or electrical shock may occur.

Insufficient Airflow

If your HVAC system loses efficiency, it will have trouble handling harsh temperatures or even regular everyday temperatures. When your HVAC system isn’t performing optimally, your home may not be as comfortable, and energy usage and utility bills can increase.

How To Fix It

  • Start by checking your HVAC system’s air filters. Change or clean the filters that require it. (This should be done regularly.)
  • Remove debris or blockage from around your outdoor central unit.
  • Remove debris or blockage from the surface of grills, ducts, and vents.
  • Contact a duct cleaning service to clean your ducts thoroughly. Duct cleaning requires special tools, so you must contact a professional.

Temperatures Throughout the Home Are Uneven

When different rooms in your home receive varying amounts of hot or cold air, the temperature distribution is uneven.

How To Fix It

  • Check for dirty air filters. Clean or change them if necessary.
  • There’s a good chance poor insulation is to blame. If possible, inspect your home’s insulation. If needed, improve any weak points or contact a professional if you are unsure how to do it.
  • Use sun-blocking drapes or blinds to cover large windows. Inspect the window liners and replace them if needed.
  • Contact an HVAC professional about installing dampers, also called volume balancing dampers or duct dampers.
  • Think about having a zoned HVAC system professionally installed. HVAC zoning systems turn on heaters and air conditioners depending on which sections of your home see the most use. 

Rattling, Whining, or Squealing Noises

When your HVAC system is running, you may hear rattling, squealing, whining, and other noises. These are signs of a problem. Squealing or whirring sounds often indicate issues with moving parts, and rattling sounds often indicate debris or loose components.

These noises are annoying, and significant HVAC system damage may occur if left unchecked.

Caution: Given the danger and complexity of working with moving parts, contact an HVAC professional promptly to resolve the issue and prevent further damage.

How To Fix It

  • Contact an HVAC professional to inspect the system’s moving parts and lubricate them, if necessary, according to the manufacturer’s specifications.
  • Have an HVAC professional inspect the system and tighten any loose screws, fasteners, or bolts, specifically for the blower motor to decrease rattling noises.
  • Since dirty air filters can restrict airflow, the HVAC system may have to work harder to compensate, potentially making more noise. In this case, the air filter may need to be changed or cleaned.
  • If your ducts are damaged or loose, you may hear banging or rattling noises when air passes through them. Have a professional examine and, if necessary, secure loose duct connections. Repairing or insulating the ducts may also be required to reduce noise.
  • If your HVAC system is outdated and continues to be noisy, consider upgrading to a newer, more efficient model designed for noise reduction.

Evaporator Coils Are Dirty

Dirty evaporator coils are a common problem in HVAC systems. Dirty evaporator coils may reduce an air conditioning system’s performance and efficiency.

Over time, debris, dust, and other particles may block the indoor unit’s coils, forming an insulating layer that inhibits heat transfer and absorption. When this occurs, the HVAC system has to work harder, reducing its ability to cool and potentially increasing utility bills. Evaporator coils are often difficult to access and require care when cleaning. Therefore, it is crucial to contact an HVAC professional promptly to clean the evaporator coils and help maintain air conditioner performance and energy efficiency. 

How To Fix It

  • Make sure the space surrounding the indoor HVAC system is kept clean and free from dust. This helps reduce the chance more debris ends up on the coils.
  • Air filters help protect evaporator coils from dust and debris, so it is important to ensure they are routinely cleaned or replaced.
  • Consider upgrading to high-efficiency air filters or electronic air cleaners to protect the evaporator coils better.
  • Improving your home’s air quality lessens dust and particle buildup on evaporator coils, which helps them stay cleaner longer. 
  • If your evaporator coils are dirty or clogged, contact an HVAC company to repair or replace them. If you don’t know how to locate your evaporator coils, please contact an HVAC professional to inspect them.
  • Arrange for an HVAC specialist to conduct regular maintenance and evaporator coil cleaning.

Hot Air Coming Out When It Should Be Cool

You have an issue when you expect cool air from your air conditioner in the summer but only get hot air. There are a number of potential causes for this.

How To Fix It

  • Cleaning or replacing air filters may resolve it.
  • Listen to your compressor; if you hear rattling or clicking sounds, contact an HVAC professional to inspect it.
  • Check for signs of low refrigerant, such as hissing noises from the evaporator coils or ice on refrigerant lines or evaporator coils. If you notice any, contact an HVAC professional. They may need to recharge the refrigerant. If you don’t know how to find the evaporator coils, please contact an HVAC professional.

Leaking Refrigerant

One of the most common issues with HVAC systems is AC refrigerant leaks, which HVAC professionals must handle. Low refrigerant levels are a potential indication of leaking refrigerant.


Refrigerant leaks can have several causes, including poor installation, wear and tear, and corrosion.

How To Fix It

  • AC refrigerant is hazardous, and leaks must be handled by professionals.

Caution: Because AC refrigerant is dangerous, do not attempt to repair this on your own.

Air Handler Problems

An HVAC unit’s air handler circulates air through the system and into the home. Air handler problems can occur for numerous reasons, including motor malfunctions, faulty wires, or dirty filters.


There are several signs of air handler malfunctions. Some include loud screeching or banging sounds when starting the system or a burning electrical smell from ducts. 

Caution: If your HVAC system has a burning smell, shut it off immediately and call an HVAC professional. 

If your home has poor air quality, even after the filters have been changed or cleaned, it may be due to a poorly functioning air handler. If there isn’t airflow, there may be problems with the blower.

How To Fix It

  • Given the dangers involved and how complicated air handlers are, contact an HVAC professional to repair them.

Encountering Short Cycling

Short cycling is when an air conditioner turns on but shuts off after a few minutes—before the room has time to cool.

Short cycling can have several potential causes, including dirty air filters, frozen evaporator coils, thermostat issues, leaks, and electrical problems. Another possible cause of short cycling is having the wrong size HVAC system for your home.

How To Fix It

  • You may be able to fix a short-cycling air conditioner by simply replacing or cleaning your air filters, as dirty air filters can cause short cycling.
  • Check the evaporator coil for ice buildup and lines for leaks. If you see either one, contact an HVAC professional. If you don’t know how to inspect the evaporator coil, please contact an HVAC company for help.

Problems With the Pilot Light

Gas-powered water heaters and furnaces may develop pilot light issues. A malfunctioning pilot light may result in a number of heating system problems, including flickering and persistent outages, and it may not ignite at all. 

Pilot light problems have several causes, such as faulty electronic ignition systems, gas supply issues, obstructed or dirty parts, and thermocouple problems. 

Caution: Working with a pilot light is incredibly dangerous. To resolve pilot light problems, contact a reputable professional.

How To Fix It

  • If you have a pilot light issue, you must contact a professional to help, given the inherent risks of working with a pilot light.

The Air Conditioner Constantly Runs

When temperatures are high, the air conditioner must run frequently. However, the system should periodically shut off to prevent it from freezing up. A continuously running air conditioner wears out quickly, leading to an expensive energy bill.

A constantly running air conditioner may have several causes, such as the thermostat being set too low or electrical trouble.


Caution: Because of the dangers of working with electricity, this must be handled by a reputable professional.

How To Fix It

  • If this occurs, the first step is to turn up your thermostat. If the air conditioner shuts off, this indicates that the temperature was set too low. 
  • If the air conditioner keeps running, contact an HVAC company. There could be multiple causes, such as problems with the compressor, damaged components, or worn electrical parts. You do not want to try to repair these yourself.

Condenser Coil Freezes Up

If an air conditioner runs continuously, it may cause the condenser coil to freeze. If it freezes, it could lead to an increased energy bill. Ice should not build up on condenser coils, particularly when the weather is hot.

How To Fix It

  • Inspect the condenser coils for ice buildup (if you know how to). If there is ice, it may be caused by a dirty air filter that needs to be replaced or cleaned. Whether the air filter is clean or dirty, it is essential to contact an HVAC professional to inspect the system to ensure there are no serious problems.

The Thermostat Malfunctions

If your air conditioner only works some of the time or turns off after running for a little bit, you may have problems with your thermostat. If the thermostat is uneven or dirty, it can cause issues such as continuous running and short cycling.

How To Fix It

  • Check to see if the thermostat light is on (this will tell you if the thermostat has enough battery power to work correctly).
  • Next, wipe debris and dirt off the thermostat. Debris and dirt may interfere with the thermostat’s signal. If you are still having problems, contact an HVAC professional.

Expensive Energy Bill

If your energy bill is higher than usual, it may be caused by an HVAC problem. It is important to note that if you are dealing with extreme temperatures, the energy bill increase may be due to that. However, if the weather is the same but your energy costs have increased, it is vital to determine the cause and whether your HVAC system is behind it.

How To Fix It

  • First, inspect your HVAC filter. It may need to be changed or washed.
  • Have an HVAC professional conduct a maintenance check.

There Is an Odor Coming From Your HVAC System

An HVAC unit should not smell; if it does, that indicates a problem. Smells that indicate trouble are mildewy, musky smells and electrical smells.

How To Fix It

  • If you smell something electrical, immediately shut off your HVAC system and contact an HVAC professional. The electrical smell may be caused by a short circuit, indicating burning wires. Do not try to fix this yourself.
  • If you smell a musty or mildewy smell, changing your air filter may fix it. However, this might not solve the problem. Leaks, clogs, and dead animals in the ductwork may also cause unusual smells. Contact an HVAC professional for the best resolution to these problems.

Regular professional HVAC maintenance is crucial for a properly functioning HVAC system.

Choosing the Right HVAC System for Denton County’s Climate

A representative discusses options with Lantana homeowners

There are several considerations when looking for the right HVAC system for your home. Since Denton County, Texas, sees temperatures above 90° Fahrenheit and under 40° Fahrenheit, you’ll want a system that will both cool and heat your home.

The following are some HVAC systems you may want to look into.

Central Air Conditioning

Given Denton County’s harsh summers and generally mild winters, central air conditioning is often optimal for cooling your home. Central air conditioners send cool air through ducts and vents to different rooms in your home. Because of its power, central air conditioning works well for large homes with tall ceilings.

You will also need a heating system in your Denton County home.

Ductless Mini-Split System With Heat Pumps

Another option for Texas homeowners is a ductless mini-split system with heat pumps. These systems offer heating and cooling and can be convenient if your home does not have ducts. These systems allow you to heat specific rooms while reducing energy use in other rooms, and they provide the small amount of heat required for the milder winters that Denton County tends to experience.

With the many options available for HVAC systems, it is a good idea to consult a professional when selecting one for your home. If you’re in Denton County, Texas, or the surrounding area, contact the experts at Cote’s Mechanical for your cooling needs.

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