Modern Mechanical HVAC is THE heating and air conditioning authority in North Carolina. Get answers to some of the most commonly asked questions about heating and cooling equipment, energy efficiency, air quality and maintenance below.
Heating, Ventilation and Air Conditioning
The most important part of HVAC maintenance aspect is maintaining unrestricted air flows. Dust, dirt, and debris are an HVAC system’s worst enemies. Whether it’s an indoor or outdoor unit, you must keep all filters clean and heat exchangers and coils free of restrictions.
We recommend that your heating and cooling system be checked and serviced twice a year; ideally a spring and fall tune-up. Also we recommend that you change your filter regularly, depending on the type of filter you have. This alone can eliminate many of the most common problems that need fixing and can significantly reduce the likelihood of a serious breakdown. A Modern Mechanical Rapid Response Agreement is your assurance that these maintenance needs are met regularly and that any potential problems are promptly identified.
Regular filter replacement helps your heating and cooling system operate at peak levels and improves indoor air quality. It is important to change filters regularly to ensure proper air flow and to keep your home free from dust, allergens and germs. Depending on the type of filter you have, you may require weekly or monthly filter replacements. Your Modern Mechanical service or installation technician will recommend the ideal filters and replacement schedules for your unit(s).
In general, Modern Mechanical recommends that you replace your disposable filters at least once a month. If you have washable filters, they should be cleaned once a month. Your Modern Mechanical service technician will recommend a replacement schedule that delivers the optimum efficiency and filtration for your specific system. With a Modern Mechanical Rapid Response Agreement, we clean and inspect your HVAC system twice each year. Part of the service includes changing the (customer supplied) filters or servicing your filtering system. Unless you have special circumstances, our service should be adequate. We recommend that you visually check filters and filtering equipment monthly. If filters look dirty, they need to be cleaned or replaced.
Most maintenance should be performed only by a qualified service technician. But here are some things that you can do to assure optimal performance:
- Keep ground mounted outdoor units clear of debris, clutter and weeds; they can reduce the airflow to the unit.
- Use caution with weed trimmers around the unit to prevent damaging control wiring.
- Keep pets away from the unit; pet urine can cause expensive damage.
You should have maintenance done on your air conditioning system at least once a year – spring to early summer being the best times. This not only ensures maximum efficiency, it enables us to foresee any possible problems that may occur in the near future.
Check to be sure that the air conditioner or furnace is turned on. Check that the breakers and the disconnects are turned on and be sure the thermostat is set correctly. Also make a note of any strange noises or smells.
Is it making strange noises? Is it cooling or heating all areas of your home sufficiently? Has it been taking longer to cool down or heat up? Have your utility bills been rising for no apparent reason? Any of these are signs that you may have a problem that needs service. In most cases, the longer you delay, the worse any underlying problems will get. So be sure to contact Horizon Services to check out your system whenever you notice anything out of the ordinary.
Heating and cooling systems sizing is based on B.T.U.H. (British Thermal Units Per Hour). Air Conditioning and Heat Pumps are also rated in tonnage. 12,000 BTUH equals one (1) ton. Residential systems can range from 1 to 5 tons.
Sizing HVAC equipment is very important from the standpoints of both comfort and energy use. Heating and cooling equipment that are over-capacity will not run as frequently or as long when it does run. In both cases, this may mean poor humidity control. It could also result in temperature variations or noticeable cycling. Over-capacity equipment will not be as energy efficient as properly matched capacity either. On the other hand, equipment that is under-sized, will obviously result in loss of comfort during temperature extremes.
Unfortunately, there’s no simple rule of thumb for determining the ideal size of system for each home. For example, depending upon the construction of your home, one (1) ton of air conditioning can cool anywhere from 300 to 800 square feet of home. The only way to insure the size of the system you purchase will be large enough to heat or cool your home, but not any larger than you need, is to have your home’s individual heating and cooling needs evaluated by a licensed professional. A Modern Mechanical Comfort Consultant will perform a FREE detailed In-Home Energy Analysis to determine a selection of systems that will work best for your home’s needs and your budget.
No. A larger heating system with more capacity delivers less comfort and costs more to operate. An air conditioner is at its least efficient when it is first turned on. A system with too much capacity will run in numerous short cycles, turning on and off repeatedly, therefore causing it to be less efficient. Also keep in mind that an air conditioner only removes humidity when it’s running, so a system with shorter run cycles doesn’t remove humidity from the air very well.
Bigger isn’t always better; its performance and efficiency that count. Before purchasing a replacement system you should always make sure your system is sized properly to match your needs and budget. Your Horizon Comfort Specialist will thoroughly assess your home and comfort requirements to determine the proper size and make the appropriate recommendation.
When purchasing a furnace, heat pump or air conditioner, ALWAYS ask about its Efficiency Ratings. They will tell you will tell you how efficiently the unit uses fuel (gas, oil or electricity). The most-frequently used efficiency ratings are:
- SEER (Seasonal Energy Efficiency Ratio): This ratio tells you the amount of cooling your system will deliver per dollar spent on electricity The SEER rating of any unit can range anywhere from 13 to 20. The higher the SEER the more efficient the system will be and the less it will cost in the long run to own and operate.
- HSPF (Heating Seasonal Performance Factor): Similar to SEER, it is a measurement of efficiency of the heating portion of a heat pump. HSPF ratings range from 6.8 to 10; high-efficiency units have efficiencies of 7.5 HSPF or above.
- AFUE (Annual Fuel Utilization Efficiency ratio): A measurement of the percent of heat produced by a furnace for every dollar of fuel consumed. The higher the AFUE rating, the lower the fuel costs. All furnaces manufactured today must meet at least 78%. Older furnaces (10 – 15 years or older) may fall below this minimum. Furnaces with AFUE ratings from 78% to 80% are considered mid-efficiency; ones with AFUE ratings above 90% are considered high-efficiency.
- MERV (Minimum Efficiency Reporting Value): A filter rating system relating to the size of the holes in the filter that allow air to pass through. The higher the MERV rating, the smaller the holes and the higher the efficiency in capturing contaminants. MERV rating range from a low of 1 to a high of 16.
- ENERGY STAR: An Environmental Protection Agency designation attached to HVAC products that meet or exceed guidelines for high-efficiency performance above the standard government minimums.
A few quick tips:
- Clean and replace your filters frequently.
- Install shades, drapes, shutters, or screens on windows that are exposed to extreme sunlight to keep room temperatures at moderate levels.
No. Every system is designed to cool a certain number of square feet. By closing registers and doors in certain rooms, you disrupt and decrease the systems’ airflow and efficiency. Your system will have to work harder to cool less space, making it cycle more and become less efficient.
There is no exact answer for how long your system should run during each cycle. The average air conditioner is sized to remove the heat from your home as fast as it comes in. Therefore, ideally, on a 100° day the system should be able to keep up with the incoming heat, but not gain on it and not be able to turn off. The cooler it is below 100°, the more the system will cycle on and off. So it depends on the environment of each individual home and the condition of the equipment.
Generally speaking, a unit that is either on or off is less expensive than one that keeps cycling on and off repeatedly. Every time your system starts up, it will use a lot of electricity and not produce much cooling. That’s why a smaller system is often more economical to operate: even though it runs nonstop and may deliver less comfort, it will usually consume less power than a larger system that cycles on and off.
The air temperature produced by your system depends on the temperature of the air going into it. Generally, the air produced should be 15°-20° below what enters the system. So if the entering return air is 80°, the exiting supply air should be about 60°-65°. However, that only works on a system that is operating properly and has been running at least 15 minutes on a warm, dry day with a home that is about 80° inside. On a milder day, with an indoor temperature 70°, the air coming out should be 50°-55°.
Temperature settings depend on the time of year and your personal preferences. In the summer, the average temperature setting is 75°-80°. In the winter 68°-72° is the norm. Remember, when leaving your house; try to avoid drastic temperature changes. Do not set your temperature back more than 5°; this will cause your unit to work harder to achieve the desired temperature setting.
Because they are electronic, programmable thermostats are more accurate and efficient than thermostats that contain mercury. Plus, they allow you to automatically control the temperature in your home at different times of day without ever touching your thermostat.
Variable speed refers to a furnace’s or air handler’s indoor blower motor. Different speeds control the flow of air throughout your home. Variable speed blowers automatically change speeds to meet the different airflow needs of the heating and cooling cycles. Variable speed motors can use 1/7th the energy and are excellent for customizing comfort levels in different zones of your home. A variable speed motor can also help clean the air and control the humidity.
Two-stage heating means a furnace has two levels of heat output: high for cold winter days and low for milder days. Two-stage furnaces start in the first stage, instead of reaching full capacity all at once. That means there is no sudden blast of air. The low setting meets household heating demands 80% of the time, allowing a two-stage unit to run for longer periods and provide more even distribution of heated air. Because the furnace operates mostly in its lower-capacity first stage, it burns less fuel than a furnace that always runs at full capacity and then has to shut off when the heating demand has been met.
Heat pumps are very effective for homes in North Carolina. They are a good choice whether you rely on electricity or natural gas for your energy needs.
A heat pump is an all-in-one heating and air conditioning system that works year-round for comfort. During warmer months, a heat pump works as a normal air conditioner. In colder weather, a heat pump collects heat from the outdoor air and transfers it inside the home. Even when outside air feels cold, there is still heat in that air. On very cold days when there’s not enough heat in the outside air to meet the thermostat setting, an electric heater supplements the indoor air to warm a home. This process is quite efficient as it produces two to three times more heat than the energy it uses.
A heat pump can also be an effective add-on option to use in conjunction with an existing gas, propane or oil furnace. With this dual-fuel option, the two systems share the heating load, but never function at the same time. Each system operates when it is most cost effective.
Yes, this is normal. A heat pump generally produces air that is around 80° and provides even comfortable, heating around the house – not a blast of intense heat. However, 80° may feel cool to your hand, which is usually closer to 90°.
Totally normal. During the cold weather months, frost can accumulate on the outdoor coil. This can cause the heat pump to go into a defrost cycle anywhere from 1-10 minutes, depending on the amount of ice on the coil. This is temporary; the system will return to the heating mode once the ice is gone.
Simply put, all Heat Pumps in northern climates (below 35 degrees) need a supplemental heating source. Usually it is in the form of electric resistance heating - at the indoor unit. This is an all-electric Heat Pump, but it could also be a gas, oil, or hot-water back-up system as well. The supplemental heat is also referred to as "second-stage" or "back-up" heating, with "first-stage" being the Heat Pump only. Emergency Heat is when you use your supplemental heat (2nd stage) by itself, without the use of your heat pump (1st stage heat).
Different systems and thermostats have different ways of determining when the second-stage heat comes on to assist the heat pump, but it is always done automatically. The two stages will work together in the colder months, and it is not necessary to switch your thermostat to Emergency Heat. So now we know that Emergency Heat is basically when you use your supplemental heat by itself.
As the name implies, it is only used in emergency situations. It is used when there is something wrong with first-stage heating (the Heat Pump itself). In other words, if you notice your house is cold and it isn't heating properly and you went outside and noticed that a tree fell and crushed your heat pump, that would be a good time to switch to Emergency Heat.
Or if you look at your Heat Pump and it has turned into a block of ice due to a malfunction. At this point, it isn't capable of providing any heat. Simply turn the thermostat to Emergency Heat and call for service.
When switching to Emergency Heat, the red indicator light will go on. And it will stay on until you stop using the Emergency Heat. This just lets you know you are in emergency mode. On a call for heat, no signal will be sent to the outdoor Heat Pump. Only the indoor unit and the back-up heat will run. On all-electric systems, this will provide enough heat to keep you going until the Heat Pump can be fixed. Gas/Oil/Hot-water system should provide plenty of heat.
If you have an all-electric heat pump, then the answer is a definite YES! It is much more expensive to run your heat pump on Emergency Heat. And as the name implies, should only be run in an emergency until your heat pump can be repaired. Now if you have Gas or Oil heat for your backup system, then the answer isn't so clear. It depends on the cost of your fuel, the efficiency of your heating system, compared to your electric rate and so on. But it is safe to say that the price increase won't be as much as an all-electric system.
As explained earlier, the Emergency Heat light will be on if your thermostat is set to Emergency Heat. But if your thermostat is not set to emergency heat and the light is on, then that usually indicates a problem with your heat pump.
Several factors that can cause system freezing. First, if running in the cooling mode check your filters; restrictions in air flow can lead to freezing. Next, thaw the system out by turning off the cooling and running the fan. Also, try turning the system to the heat mode until the ice has melted.
If the problem recurs after checking for air restrictions and thawing your system thawed, schedule a service call with Modern Mechanical. Our service technicians will check the refrigerant level. They may also have to clean the evaporator coil, check the blower speed and check for any intermittency in blower operation. A service technician can also evaluate other conditions that may make your system prone to freezing and recommend the best course of action.
I.A.Q. stands for Indoor Air Quality. Today, various products are available as add-ons to your existing heating and cooling system to improve the quality and healthiness of the air inside your home. These items include
- Electronic- or Media-Type Air Filters: Filtering the air within your home will help eliminate smoke, pollen, odor, dust mites and allergens. This will allow you to breathe easier, sleep better and enjoy your home more.
- Whole-House Humidifiers: Whole-house humidifiers provide consistent humidity levels throughout the home, and some models even adjust the humidity level automatically. The average heated home has a humidity level of less than 20%. The recommended humidity level in the winter should be between 35% and 45%.
- Air-to-Air Heat-Recovery Ventilators: These ventilator systems remove stale air from inside the home, while bringing in fresh air from the outside that is warmed during the transfer process.
An air quality system can greatly improve both your comfort and your health. The areas of air quality to consider are (1) purification, (2) filtration, (3) humidity control, and (4) ventilation. A wide number of air quality features come standard with many new heating and air conditioning systems; others can easily be added to existing systems. Contact Modern Mechanical to discuss your air quality options.
Whole house media filters can greatly improve home air quality and comfort levels. If you suffer from allergies or have pets, they’re a must. Modern Mechanical offers The Trane 5” Perfect Fit Media. Talk to your Modern Mechanical Comfort Specialist to discuss your options.
A heat exchanger is a piece of metal designed to separate the safe warm air that is circulated through your home from the poisonous carbon monoxide gas created during the combustion process when you operate your furnace.
The natural heating and cooling cycles of a furnace can lead to cracks in a heat exchanger. A furnace that is being overworked or stressed is more likely to have a premature breakdown and potential carbon monoxide leak. Dirty air filters, blocked vents, and burners that are not firing properly and disrupting the combustion process can all contribute to the detrimental stress that may lead to cracks in a heat exchanger.
If a crack in the heat exchanger allows carbon monoxide to escape into your home you may experience dizziness, light-headedness, flu-like symptoms, or even death by asphyxiation. Carbon monoxide limits the body’s ability to take in oxygen. This is an extremely dangerous situation to have in the home, because the effects of carbon monoxide poisoning may be gradual and undetected.
Very concerned. Carbon monoxide (CO) is a gas produced during the combustion of fuels. It’s colorless, odorless, tasteless…and can be lethal. Even trace amounts can impair your brain function and impact your health. Cracks, leaks, obstructions and other malfunctions in your heating system can cause carbon monoxide to develop and accumulate.
Short-term exposure to carbon monoxide usually results in flu-like symptoms: nausea, headaches, dizziness, fatigue. Long-term exposure can eventually lead to unconsciousness or death.
Modern Mechanical recommends the following to minimize carbon monoxide risk:
- Keep heating equipment in good repair by scheduling regular inspection and maintenance.
- Keep furnaces, chimneys and vents free of obstruction. Watch out for birds, squirrels and other animals who sometimes build nests in these areas.
- Install a carbon monoxide detector, available at any home supply store.
- Periodically open windows in winter to let in fresh oxygen-rich air inside and let out any potential carbon monoxide.
- If you use an older gas stove or heater, look at the color of the pilot light. The flame should be at least 80 percent blue. If the flame is mostly yellow, it could be producing carbon monoxide, so have the unit checked by a professional immediately. Be sure to tune up your gas system at least once a year.
Today’s modern heating systems burn cleaner than older systems, minimizing or eliminating your risk of carbon monoxide exposure. Contact Horizon Services for more information.
Extremely important. Sound intensity is measured in units called decibels (dB). A normal conversation is about 60-70 dB. A telephone dial tone produces 80 dB; a lawn mower produces 107 dB or more. Sustained exposure to sound levels of 90-95 dB may lead to hearing loss, so it’s important to own the quietest heating and cooling system you possibly can.
The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) recommend a household humidity level between 30 and 60 percent.
The average comfort range for relative humidity in a home is from 30 to 35%. When cool outdoor air enters your home, it tends to dry out as it warms up, which can cause static electricity build-up and sinus problems. A humidifier will add moisture back into the air and minimize these problems during the winter months. However the humidity level achieved in a home is effected by how tight a home is, how often the doors open and close size and style of humidifier.
Yes. Several manufactures have developed new systems that contain environmentally-friendly refrigerants such as R-410A and similar blends. 410A is a chlorine-free coolant that is safe for the Earth’s ozone-layer and delivers superior cooling than traditional refrigerants. In fact, in 2010, systems that used R-22 will be phased out and replaced with 410A systems. And by 2020, no more R-22 can be manufactured.
Not an easy question to answer, but here are some factors to consider:
- The age of the current system. Today, any system that is more than ten years old is probably behind the times in terms of efficiency.
- Does the current system provide the level of comfort that you want? There is a growing difference between “builder grade” and consumer choice in what a system can offer in terms of comfort and convenience.
- How much will the repairs cost…and how many more repairs will you need in the future? Is keeping an older system operational worth the time, the money and the inconvenience? Sometimes you need to know when to cut bait and say goodbye to your old heater or air conditioner.
At Modern Mechanical, we can work with you to prepare a side-by-side cost-benefit analysis so that you can compare whether it is more advantageous for you to keep your current system or replace with a newer one.
If you’re deciding on a new system and have not kept up with advances in the industry, you will be amazed at the number of choices that you have to make. Today’s comfort systems offer a surprising number of options and combinations – from individual heaters and air conditioners to integrated or “hybrid” systems. Systems can vary widely in terms of energy efficiency and cost. The ability of systems to monitor conditions and adjust automatically has increased dramatically. And a wider variety of air quality add-ons are available than ever before.
These changes make the replacement decision even more complex than ever, so you can see how important it is to find a HVAC company that will work with you to develop a system for your situation and budget. At Modern Mechanical, our goal is to be a company that will partner with you to not only install a system that is appropriate for your situation, but then help you keep the system operating at peak performance.
All systems and units are different. Here are some rough lifespan guidelines to help you decide whether fixing or replacing is the right decision:
- Average Lifetime of an Air Conditioner: 12-15 yrs.
- Average Lifetime of a Furnace: 15-20 yrs.
- Average Lifetime of a Heat Pump: 12-15 yrs.
Keep in mind that these are just guidelines. Some units last longer than that with regular maintenance and replacement of parts. But if a unit has been repaired repeatedly, or has been run excessively, it might make more sense to replace it even sooner. Paying for repairs to an old or inefficient system often simply prolongs the inevitable. An older system that breaks down once is likely to break down again…and again. That means more emergency service calls or, worse yet, the risk of damage to your home or to other components of your heating and cooling system.
There’s also an ongoing cost factor to consider. Restoring your old system will only bring it back to its current level of energy efficiency. After you’ve recovered from the repair bills and the frustration of system breakdowns, you still won’t save on your energy bills.
Some replacement systems can cost less than the cost of repeated repairs. And in many cases, installing a new heating and cooling system can actually pay for itself in energy savings within a relatively short time.
Also, when replacing a heater or air conditioner, it is usually best to replace both units at the same time. This way, you’ll save on installation costs and both units can be serviced on the same maintenance schedule and have the same approximate lifespan.
Here are some general rules of thumb when you are ready to replace your existing equipment:
- Choose a manufacturer that has a good reputation for quality and durability.
- Choose a model that with a high efficiency rating to bring you better comfort and lower your seasonal energy bill.
- Choose the correct equipment size and system for your home.
- Don’t just buy a unit just because it is on sale and seems like a great deal at the time; do some research on the product or ask the installation representative for more product information.
- Finally, choose a reliable company with excellent customer satisfaction and a track record of service after the sale. Talk to your friends and neighbors. Check out contractor ratings and reviews online from organizations like Angie’s List, Yelp, Google or the Better Business Bureau. Chances are you’ll get plenty of recommendations for Modern Mechanical!
Here’s checklist of options:
- Make sure that your home’s current HVAC system is properly maintained and adjusted.
- Change attitude and habits. Rethink your clothing, your appliances and your activities in your home – anything that can produce lower temperature settings in winter and higher temperature settings in summer can help control energy use.
- Explore energy-saving add-ons for your current system: thermostats, humidifiers, and zoning controls.
- Plant trees and landscape for summer shade and winter sun.
- Add insulation, install weather stripping and plug air leaks throughout your home.
If your current system is in need of replacement, your efficiency options are expanded and the potential for savings compared to your existing system can be quite dramatic. Modern Mechanical can provide the consultation and information about all options and system combinations that might be right for your situation.
Due to the many different makes, models and customer needs, price is an issue that can only be solved by doing a thorough evaluation of your home and existing equipment. At Modern Mechanical, there is no charge for an in-house replacement proposal.
Modern Mechanical has teamed up with Wells Fargo. We are able to offers several financing options with approved credit. Your Modern Mechanical Comfort Specialist can recommend the financing plan that’s best for your needs.
A Modern Mechanical Rapid Response Agreement is a great way of protecting you in the event of sudden breakdowns in equipment and is your guarantee that you’ll receive regularly scheduled maintenance. With a Rapid Response Agreement, you will receive priority service for heating and air conditioning calls (routine or emergency), a 15% discount on all repairs, and no additional charge for overtime or emergency calls. What’s more we’ll make sure that regularly scheduled tune-ups and filter replacements are done on time to keep your system working at peak performance.
One of the biggest problems in the heating and air conditioning industry is the lack of trained professional technicians. Poorly trained service technicians and shoddy installation are the two primary reasons that consumers need to keep having a repairman come to their home. North American Technician Excellence, Inc. (N.A.T.E.) is the leading independent certification body for technicians in the heating, ventilation and air-conditioning (HVAC) industry. They establish the industry’s standards for excellence and administer the training, testing and validation procedures for meeting those standards. That means that our skills, knowledge and commitment to service are growing continuously.
Many companies in the HVAC industry don’t express the need to be there for their customers after installation or service of heating and cooling systems. But a solid, good reliable company, such as Modern Mechanical, will stand behind its work. One way is through our Rapid Response Agreements which guarantee our workmanship and provide you with priority service. Another is our 100% Customer Satisfaction Guarantee: if you’re not completely satisfied with our service we’ll do whatever it takes to make it right. Remember, you are spending a lot of money on repairs or replacement of equipment and the last thing you have to worry about is if it was done right! We encourage consumers to research a company’s background, ask a friend or neighbor, or see recent work that they have done.