Most Common Causes of AC Short Cycling

Short cycling occurs when your air conditioner shuts off before it can complete its entire cooling cycle. When your AC turns on, it will usually need to run for anywhere from 10 to 20 minutes to cool your home completely. If the AC turns on and quickly shuts off again within a couple of minutes, there might be a major issue causing your unit to short cycle. Short cycling often happens due to overheating, but it can also occur due to faulty, malfunctioning, or worn-out components, this is where our AC repair services come in.

Short cycling is a serious issue for several different reasons. Not only will it affect your AC's ability to keep your home cool, but it also stresses the entire system. This can result in major repairs or cause your AC unit to burn out entirely. To ensure this doesn't happen, let's take a closer look at some issues that can cause an AC to short cycle and how to address them.

HVAC Air Filter Is Clogged

The least-complicated reason your AC might short cycle is that you need to replace your air filter. If the filter is clogged, there won't be enough airflow to keep your AC working properly. This results in heat getting trapped inside the system, which can cause the condenser to overheat.

The AC condenser outside your home has a safety mechanism that will automatically trigger if it overheats. When this trigger is activated, it instantly shuts the system off to ensure the high heat doesn't damage any of its components. If the air filter is extremely dirty, it sometimes takes just a few minutes for the AC to overheat on hot days.

A dirty air filter is also one of the many reasons your evaporator coil might freeze. If this happens, it can also lead to the system overheating or failing to produce any cold air. The only thing you can do in this situation is to turn your AC off until the coil completely thaws out.

Evaporator or Condenser Coil Is Dirty

Your AC system has two different coils that work to absorb or release heat. Inside your home is the evaporator coil, which uses refrigerant to remove heat from the building. The unit outside your home houses the condenser coil, which disperses this heat into the outside air. These coils often become caked with dirt and dust, preventing them from working as they should. This happens because the caked-on grime insulates the coil and prevents air from reaching it.

A dirty evaporator coil will usually freeze quickly. If no hot air can reach the coils, the refrigerant stays too cold, and the pressure drops. This results in the condensation on the coil turning into ice before it can drip away.

If the condenser coil is dirty, it won't be able to release heat as easily. This can cause the condenser to overheat and shut down. In either case, the best solution is to have a technician clean the coil and test it to see if a good cleaning solves the problem.

Condenser Unit Is Clogged with Debris

The sides of the condenser unit often become clogged with leaves and debris, which prevents it from getting proper airflow. If there isn't enough air to help cool it down, it will again overheat and shut down. To fix this, simply inspect the sides of the unit and vacuum or brush away any debris.

Refrigerant Level Is Low

All AC systems require a specific amount of refrigerant to function well. If the refrigerant level is too low due to a leak, it puts much more stress on the compressor and can cause it to overheat. A refrigerant leak is also one of the main causes of a frozen evaporator coil. Your only option in this situation is to have a technician check the refrigerant level and the system for leaks. After fixing any leaks, they will recharge the system with more refrigerant.

Thermostat Is Malfunctioning

Your short cycling issues may not have anything to do with your air conditioner. Instead, they could be caused by an issue with your thermostat. Over time, thermostats may start to malfunction and no longer measure temperature accurately. When this happens, it might signal the AC to shut off too soon because it registers that the home is cooler than it actually is. A malfunctioning thermostat could also cause your AC to run much longer than it needs to and your house to become too cold.

Short cycling might occur if the thermostat is too close to a vent. In this case, the cold air from your AC vent will make the thermostat register a lower temperature than the rest of the house. This can also happen if your thermostat is in part of the home that is always colder. In either case, the only real solution is to have a professional move the thermostat to a better location within your home.

Low-Pressure Control Switch Is Faulty

Inside your AC condenser, there are control switches that shut off the unit if the refrigerant pressure gets too high or too low. Either issue can put a massive strain on the compressor and potentially cause it to burn out. In some cases, the low-pressure switch stops working correctly and will signal the system to shut off when the pressure is normal. The only way to identify this problem is to have an AC technician inspect the control switch to see if it works correctly. If it doesn't, your technician will need to replace it to eliminate the short cycling.

Compressor Motor Is Starting To Wear Out

If your compressor motor isn't working well, you will likely need to have a new AC unit installed. Compressor motors fail due to normal wear and age. Short cycling can also speed up the rate at which the compressor motor wears out due to the added stress. Unfortunately, this problem will eventually prevent your AC from turning on at all.

If your AC unit was installed in the last five years, the compressor motor might have warranty coverage. If this is the case, you might want to proceed with a compressor motor repair. While you will still have to pay labor costs for the job, using your warranty should still be cheaper than installing a new AC unit.

If your AC isn't under warranty, it's almost always better to replace the entire unit instead of just the motor. In most cases, you'll pay approximately the same price for either.

Award-Winning AC Services

At TR Miller Heating, Cooling & Plumbing, our technicians will quickly get to the bottom of your short cycling issues. We service all makes and models of air conditioners, and our skilled staff performs the most complicated AC repairs. We are also ready to help if you need to replace your old AC with a new model, and we carry a wide selection of highly efficient units for any size of home. We also repair, install and maintain residential heating and plumbing systems in Plainfield and throughout the Greater Chicago Area. Give TR Miller Heating, Cooling & Plumbing a call to schedule your HVAC service!

BTU Measurements and HVAC Units: How They Work Together

Heating and cooling power for HVAC systems is measured in BTUs, or British Thermal Units. Similar to watt and voltage measurements for electricity, the BTU is a unit for measuring the addition and subtraction of heat from a space.

The BTUs are listed with all the other technical specifics on each HVAC system you shop for. More BTUs translates to more heating and cooling power.

As you shop, you will notice that HVAC systems have a tonnage calculation as well. The tonnage is the BTU tonnage. This is shown as BTUh, which is British Thermal Unit per hour. Many people know that 2,000 pounds is also a ton. When tons are calculated for heat, one ton is equivalent to 12,000 BTU.

Residential HVAC systems typically range from 18,000 to 60,000 BTUh. A 60,000 BTUh system is also called a five-ton HVAC system. Any system over five tons is considered a commercial system.

Most commercial systems range from two tons to 30 tons. These have a completely different structure from residential systems, which are stand-alone units. The modular nature of commercial systems means that each subsystem can be modified independently. Some commercial HVAC systems can even simultaneously heat certain parts of the building and cool another.

Estimating BTUs for Your House Size

Professional estimating methods are exceptionally reliable. Asking your HVAC installer and sales team about their estimates regarding the efficiency of your ductwork, the placement of the vents, and other details will always help you get better results.

Many homeowners also rely on a professional Manual J assessment to get detailed calculations for their HVAC needs. The Manual J will include estimate factors like:

  • Sun exposure
  • Family size
  • Insulation
  • Square footage
  • And more

Your HVAC services professional can complete a Manual J for you. You can also get one from an energy auditor. The energy auditor will inspect your home to do the Manual J.

Professionals who calculate how much heat goes in and out at certain times also use BTUs in those measurements. They may assess things like the insular value of a window, whether the sealing around windows and doors is efficient, and how well the insulation in the walls is working. These measurements will help you assess the amount of time your HVAC system runs each day as well as the BTU requirements for the AC and furnace. In the case of the AC system, the amount of heat absorbed and taken out of the house per hour is measured in BTUh.

Getting the Right Number of BTUs

Buying a system with too many or too few BTUs causes technical HVAC difficulties. You run the risk of wearing a system out early if it is too small.

A small system is likely to run all the time without achieving the heating or cooling level the home needs. An undersized AC unit will experience strain and won't be able to get enough electricity stored inside the capacitator, wearing things out quicker. You'll also have a lot of noise from the system's longer run times. Undersized furnaces may turn on and off frequently without effectiveness. In some cases, they will run 24 hours a day without heating the building up.

An oversized system will use much more energy than is advisable. It will also be highly likely to turn off before the system has completed a full cycle. The early shutoff will cause the compressor in the AC unit to turn off early, resulting in high humidity. Your air conditioner will also turn on and off constantly instead of doing a thorough job of working through the air throughout the house.

In the end, this will also wear your air conditioning unit out early. It's important to get the right size unit!

Using Kilowatts and BTUs to Estimate Potential Energy Costs

A professional can help you estimate the amount of electricity you will use with each system you look at. The BTU calculation does help you estimate the kilowatt usage. You'll need to consider the amount of power you have flowing through your whole house and assess the breakers and circuits to find out your capacity on a new unit.

It's not uncommon for people to add more breakers and circuits to their home as they install HVAC systems. You may even encounter some wiring that needs to be redone to keep things efficient.

Once you've assessed the electrical capacity, you can start with the estimated average requirement of 20 BTUs per square foot of space inside the home. This won't do the whole calculation in detail. However, it's a great starting point when assessing your kilowatt usage. Many people work off the local average energy costs using this number.

Things That Will Impact Your System Requirements

One of the major influences is the ceiling height. Between houses with similar or the same square footage, the one with higher ceilings will typically have higher energy bills. Houses have been built with 8-foot ceilings as a standard measure since about 1900. But many people like higher ceilings in at least one part of the home.

You will need a larger to heat and cool the house if the ceilings reach the 12-foot range.

Windows tend to expand in size as ceilings rise, which can raise the BTU requirement for your system. Windows have a large amount of variance in regard to their insulation capabilities. It's important to look at the SEER rating on your windows as you assess your HVAC power needs.

The SEER rating will give you a good idea regarding how much heat the window lets in and out. This includes the extra heat that comes in from direct sunlight, which can be a significant source of heat in many areas. Note that the quality of the installation on each window, whether it has damage, and the sealing condition will affect the final insulation value heavily.

The insulation values for the walls and roof are also a huge factor. Many people have sections of their home that don't heat or cool evenly, and better insulation will help even the temperature out. The ductwork and usage of things like fans inside will also be part of the energy assessment.

Experienced Professionals

TR Miller Heating, Cooling & Plumbing is a third-generation family company serving the Plainfield, IL area. We repair and install HVAC units, including mini-splits, central units, boilers, radiant heating, and furnaces. We also provide UV air filter systems, filter changes, and air handlers. Our plumbing services include slab leak repair, sump pumping, burst pipe repair, gas leak detection, toilet repair, drain cleaning, water heaters, and tankless water heater installation. We received an Angie's List Super Service Award as well as a Customer Care Excellence Award. We have also been named an American Standard Dealer of the Year. We offer straightforward pricing for all our customers, and we work on all brands. We provide emergency repair services, and we are proud to stay up to date on the most cutting-edge technology.

Call TR Miller Heating, Cooling & Plumbing today to find out how we can help you.

Is a High Ceiling in a Home an HVAC Factor?

Vaulted ceilings can improve the look of a home or business in Plainfield, IL. Plus, the room feels grander when you walk into it and has increased overhead space. However, you may wonder how ceiling height impacts your home's heating and air conditioning system.

Why Are Vaulted Ceilings More Expensive to Heat and Cool?

There are three key reasons why heating and cooling a home or business with high ceilings is more expensive. First, the higher top increases the home's volume or cubic footage. Second, a high ceiling, especially vaulted ceilings, is more difficult to insulate. Third, hot air rises and collects in vaulted ceilings. This last factor significantly impacts how hard your furnace or air conditioner needs to work to bring your home to a comfortable temperature.

Why Cubic Footage Is More Important Than Square Footage When Discussing HVAC Function

Homes are typically measured by square footage. Square footage is the amount of floor space in a home. A 2,000-square-foot home with a flat ceiling and a 2,000-square-foot home with a vaulted ceiling have the same floor space. However, the house with the vaulted ceiling has an extra area that needs to be cooled during the winter and heated during the summer.

For example, a 50,000 BTU furnace is rated to heat a home of 2,000 square feet. However, this rating is based on the idea that the house has 8-foot ceilings. A furnace's square-foot rating is based on the average ceiling height in most homes. If you have a vaulted ceiling, your furnace will need to heat all the air in the house.

That air is measured not as square feet but as cubic feet. If a home or office has vaulted ceilings, the ceilings could be 10 feet or taller. A 20,000-square-foot home with a 10-foot ceiling may need a furnace that produces between 60,000 and 70,000 BTUs. The more powerful the furnace, the more energy it will consume and the more expensive it will be to run.

Using a 50,000 BTU furnace in a home of 20,000 square feet with 10-foot ceilings means the furnace will not produce sufficient energy to heat the home adequately. It will constantly cycle to keep up with the house's heating needs. This equates to a higher bill, wasted energy, and frequent maintenance as the furnace will likely break down sooner.

The Challenge of Insulating Vaulted Ceilings

A vaulted ceiling in a home will cut into its attic space. In modern homes, most attics are full of several feet of insulation with an R-value of 49 or higher.

However, with a vaulted ceiling, the interior ceiling drywall sits just a few inches from the exterior home cladding. With this limited space, the insulation R-value is much lower, at around 40.

R-value describes the resistance value of the insulation. A higher R-value means that it is harder for temperatures from one side of the structure to travel through the insulation and move to the other side.

A low R-value during the summer months means that it is going to be easier for the outdoor heat to penetrate the insulation and affect the indoor temperature. This means that your AC unit will have to work a lot harder to keep your home cool. Conversely, during the wintertime, a low R-value means that it is easier for the heat produced by your furnace to escape your home through your roof. Your furnace will have to work harder to maintain a comfortable indoor temperature.

Hot Air Rises

Vaulted ceilings increase HVAC costs because heat naturally rises since hot air is lighter than cool air. During the winter, the heat produced by your furnace will fill the void created by your vaulted ceiling.

This is problematic because although a vaulted ceiling looks nice, you are not going to spend any time up there. All the hot air produced by your furnace is sitting up against the ceiling with a low insulation level, so the hot air is losing its temperature quickly.

You might think having a vaulted ceiling is detrimental during the winter but positive during the summer because all of the hot air from the house is stuck against the ceiling. But you must remember that your AC unit will continue to work until it can cool every cubic foot of air in your home. This includes the hot air collected in your vaulted ceiling.

How Much More Expensive Is It to Heat or Cool a Building With High Ceilings?

It will cost more money to heat or cool a larger space than heat a smaller one. Some factors within the building will determine how much the cost increase will be.

For example, a new and energy-efficient home with a vaulted ceiling will not have the same heat or cooling loss as an older home of the same size and design. Additionally, the number of windows and the location of the windows relative to the ceiling will impact heating and cooling costs.

Older structures with tall ceilings will usually also have drafty doors and windows. The ductwork may be insufficient and the installation inadequate. Modern energy-efficient homes are designed to handle cooling and heating loads progressively.

Another factor is whether or not your home has direct exposure to the sun. A north-south home will have different light exposure than those with an east-west orientation.

At TR Miller Heating, Cooling & Plumbing, we have seen firsthand the impact that high ceilings, coupled with poor insulation, can have on our client's energy bills. Our technicians will be happy to visit your home, evaluate your HVAC needs, and recommend products, repairs, or maintenance that can help you cool or warm your home efficiently.

Mitigating the Effects High Ceilings Have on Your HVAC System

Some simple strategies can resolve comfort issues in a home or office with a high ceiling. The first would be beneficial to install a ceiling fan. A ceiling fan can be set to blow warm air down during the winter and then reversed to pull cool air upward during the summer, thereby improving air circulation and optimizing comfort.

Run the HVAC fan continuously, even when the AC or furnace cycles off. Continually circulating the air through your home helps mix cool and warm air, keeping temperatures in rooms with higher ceilings more consistent.

Enjoying the Best of HVAC Services in Plainfield

Efficiently conditioning the air in your home or office with high ceilings can be challenging. TR Miller Heating, Cooling & Plumbing has effectively helped residents in the Chicago area address this and many other HVAC issues since 2008. We are a family-owned business with more than three generations of experience. We are proud to offer seamless service, upfront pricing, and work done right the first time and every time.

Our services include HVAC maintenance, repair, and installation. We do general plumbing maintenance, installation, and repair in new and existing construction. We are proud to offer emergency services backed by straightforward pricing. Contact TR Miller Heating, Cooling & Plumbing today and learn more about what makes our products and services unique.

How to Winterize Your Plumbing in Illinois

The winters in Illinois can be freezing, and these freezing temperatures can easily damage your home's plumbing system. Frozen pipes are a frequent problem in the winter. If your water lines freeze, you obviously won't be able to use your plumbing fixtures until they thaw out. Water expands as it freezes, and therefore frozen pipes often rupture. If this happens, you'll be facing potentially expensive repairs. A burst pipe can also flood your home, which can cause severe water damage. For these reasons and more, you must winterize your plumbing before the freezing temperatures set in, and here is how to do just that.

Shut Off and Drain Outdoor Faucets and Water Lines

Your hose bibs, sprinkler system, and other outdoor plumbing are much more susceptible to freezing and breaking. To prevent this, you will need to shut off the water to any outdoor fixtures and make sure to drain the lines fully.

You can start by disconnecting and draining any outdoor hoses. If you leave the hose connected, water can freeze inside it. This can lead to pressure building up in the water line that feeds the hose bib, which can cause the water line to leak or break.

Once you've disconnected the hoses, you'll want to shut off the water supply to the hose bibs. Each hose bib should have a shut-off valve inside the home near the water line that feeds and exits the building.

After shutting off the water to the bib, go back outside and open it up to drain any remaining water out of the line. If you don't do this, any water left inside the pipe outside the building will freeze.

The last step is to cover all the hose bibs with an outdoor faucet sock. This insulates the bib to ensure that if any water is still inside, it cannot freeze.

If you have a sprinkler system, you will need to shut off the water and drain the lines. Draining the pipes requires using a powerful compressor to blow any remaining water out of the system, and this is typically something you will need to hire a professional to do to prevent damage to the system.

Make Sure Your Pipes Are Well-Insulated

Any pipes that run through uninsulated areas like an attic or crawl space or inside exterior walls need additional protection to ensure they don't freeze. To prevent freezing, ensure all these pipes are wrapped in foam insulation. This slides directly over the side of the pipe and only takes a few seconds to install. Ensure that the insulation covers the entire pipe and that there are no gaps.

Check for Air Leaks Inside and Outside

If your home has a crawl space, it is essential that it is well insulated. However, even if your pipes are well insulated, they may still freeze if the crawlspace isn't as well. In addition, most crawlspaces have air vents that lead outside. If so, you must also block these up to prevent cold air from getting inside.

It would be best if you then inspected the entire exterior of the building around the foundation. If you see any cracks, make sure to seal them well using spray foam insulation or caulk. Even small cracks can let lots of frigid air inside, increasing the risk of your pipes freezing.

Once this is done, go back inside and check for air leaks around your windows and doors. Check that the caulking and weatherstripping are in good shape and replace or reseal as needed. You should also feel for leaks around any electrical outlets or switches located on exterior walls. Sometimes there isn't enough insulation around these to prevent air from leaking inside and potentially causing any pipes in that wall to freeze.

Tips for Extreme Cold

The previous steps should be sufficient for most of the winter. However, when freezing temperatures are predicted, you should also take additional steps to ensure your plumbing doesn't freeze. One of the best and easiest things you can do is to leave your faucets slightly open whenever the weather is frigid. This ensures that there is always a trickle of water running through the pipes. This is important since the water won't be as easy to freeze when it is running. Also, heed the region's water pressure warnings during this time.

You should also make sure to open the cabinets below all your sinks. This allows warm air to circulate inside the cabinet to help prevent the pipes from freezing.

You will also need to ensure that the house temperature does not drop below 55 degrees. If it gets colder than this inside, there won't be enough heat inside to prevent the cold water flowing into your pipes from freezing.

Fully Winterizing a Home

If you plan on leaving the house vacant for any prolonged time during the winter, you will need to take additional steps to ensure your plumbing is fully drained and winterized. If no water runs through your plumbing for a long time, it increases the chances of the pipes freezing. You also need to ensure that you have a continuous heat source in the building while you're away so that the temperature doesn't drop below 55 degrees.

Fully winterizing a home is always best done by a professional plumber as it will be necessary to blow out all of the pipes. The first step involved is shutting off the main water supply. The plumber will then open all faucets and plumbing fixtures. This is important as any closed faucets can create a vacuum in the plumbing system, which will trap water inside the pipes. Finally, an air compressor blows out the water lines to ensure they are dry.

All toilets must be flushed repeatedly to remove as much water from the tank as possible. Then, antifreeze is added to the tank to prevent any remaining water from freezing. Any sinks or drains that have a P-trap will also need antifreeze. This trap always contains a small amount of water and is responsible for creating a seal that prevents sewer gases from coming back into the home. Putting antifreeze into the drain ensures that the water in the trap won't freeze and break the pipe.

The last step is shutting off the water heater and thoroughly draining the tank. This prevents the water inside the tank from freezing. It also ensures that the heating elements won't get damaged, which can quickly happen if the unit runs while the tank is empty.

Award-Winning Plumbing Services in Plainfield

If you need help ensuring your home's plumbing is fully winterized, you can count on the TR Miller Heating, Cooling & Plumbing team. We are a family-owned company and have been providing plumbing services to residents of Plainfield and throughout the Greater Chicago Metro area since 2008. All our plumbers are fully licensed and highly trained, and we always take the time to make sure the job is done right the first time. No matter what plumbing service you need, we always provide honest, upfront pricing with no hidden fees. To schedule an appointment to winterize your plumbing, give us a call today.

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