Ask the Expert
You've got questions and the experts at Davis Mechanical Corp have the answers. Below you'll find a collection of previous questions and the expert answers. If you'd like an answer to your question, just click the link below, enter your question and the experts will get you an answer.
Recently Asked Questions
What is the average life expectancy of equipment?
Most systems have a lifetime of 10 to 20 years. As your equipment gets older, it's efficiency can decrease dramatically. You may notice that it gets noisier and needs repairs more often. When a unit begins to show it's age, you have two choices. You can overhaul the system or replace it. Because heating and cooling technologies improve over time, a new system designed with newer, more energy-efficient equipment makes sense, especially if your system is 10 or more years old. We can estimate the cost of a new system as well as a payback schedule that will show you how newer technology will pay you back in lower energy usage.
Can I just replace the outdoor unit on an older system to save money?
No. Replacing only the outdoor unit will lower the efficiency of the unit. In fact, you can lose up to 15% of the unit's efficiency! Even worse, your system may fail sooner than normal and most manufacturers' warranties will be voided. You should always replace the indoor cooling coil with the outdoor unit.
Will a bigger sized system perform better?
No, you don't want your air conditioner to be too big. Air conditioners control the comfort level in your home by cooling the air and by removing humidity. An oversized air conditioner will cool your home faster, but it will use more energy and will not remove humidity adequately.
A unit that is too big for your home will have short run cycles. It may take only a short time to cool the air, but the unit shuts off before enough air blows across the indoor coil where moisture condenses into water and drains from your system. Too much moisture left in the air can lead to mold and mildew problems.
These short run cycles also mean your system starts and stops more often which uses more energy and causes a lot of wear and tear. An air conditioner operates more efficiently during long run cycles.
The same holds true with heating systems. An oversized furnace will warm the house quicker, but it uses more fuel and causes greater temperature swings in the home.
Why is a system with matched components so important?
A matched system is important for a variety of reasons. One is comfort. When all your components are properly sized to your home, you can control exactly how much heating or cooling you need so you can relax. Also, a properly sized matched system enables every component to perform as designed, meaning proper cycle times are maintained, humidity is controlled, and system sound is minimized.
Another reason matched systems are important is efficiency. Most systems people buy are too large for their homes, which uses more energy than needed for your home. A matched system outlined by a dealer who has completed a load calculation for your home provides just the right amount of heating and cooling you need so you get the most value for your utility dollar.
How often should I change my air filter?
At the risk of telling you something you're tired of hearing, replace the air filter in your furnace on a regular basis. Dirty air filters reduce the amount of air flowing through a system and make the furnace work harder to maintain the temperature. How often you change the filter depends on the type of filter you use, if you have pets, and the size of your equipment. Please give us a call and we can give you proper guidance.
Why should I switch to a high efficiency air filter?
Proper air filtration is just as important to the health of your heating and cooling system as it is to the health of your family. Without proper filtration, dust and dirt can build up on your system which impacts operation and efficiency. A high-efficiency filter will remove more dust, dirt, pollen, mold, and other particles from the air. If you suffer from allergies or other respiratory problems, you should strongly consider a high-efficiency filter. No matter what type of filter you have, make sure you change it regularly.
Should I have my furnace and air conditioner serviced every year?
Yes. Keeping your system properly maintained will lower energy and repair costs, prevent breakdowns, and prolong the life of your equipment. Neglecting necessary maintenance ensures a steady decline in air conditioning performance while energy use steadily increases.
Why should I purchase a service agreement?
Without warranty coverage, a breakdown can mean significant expense in parts, labor, or both. However, with one of our service agreements, you avoid that unexpected significant expense. While no warranty can guard against every possible problem, we can explain the broad range of protection our service agreements afford.
How can I reduce allergens and improve the air quality in my home?
With a high efficiency air cleaner, you can remove up to 99% of the pollen and spores that find their way into the home. There is also a great reduction in household dust, dirt, smoke, and other air pollutants. Your indoor air will become cleaner and fresher while reducing the allergens and dust that circulate throughout the house. With a whole house humidifier, you can relieve the irritating discomfort of dry indoor air. The humidifier reduces itchy skin, scratchy throats, static electricity, and damage to your furnishings and woodwork. Since humid air feels warmer than dry air, you do not have to set the thermostat as high to feel the comfort you want. A lower thermostat setting will reduce the costs of your energy bill.
I am concerned about mold growth, what should I do?
Molds are part of the natural environment. Outdoors, molds play a part in nature by breaking down dead organic matter such as fallen leaves and dead trees, but indoors, mold growth should be avoided. Molds reproduce by means of tiny spores; the spores are invisible to the naked eye and float through outdoor and indoor air. Mold may begin growing indoors when mold spores land on surfaces that are wet. There are many types of mold, and none of them will grow without water or moisture. Click here to learn more about mold prevention in your home from the EPA.
When humid air passes over chilled cooling coils, water condenses and drips through the coils into a collection pan, from which it continuously drains. Problems with these systems may occur when this water collects and becomes stagnant when it becomes blocked, either on the coils or in the drip pan. The pan will grow mold that can infect your home with dangerous mold spores very quickly. Problems also exist when the HVAC ducting contains microscopic mold spores that stay continually present and blow contaminants around the home or office often caused by mold in other parts of your home.
You can do 3 things to prevent mold growth in your system:
- Preventative maintenance will ensure that the collection pan under the indoor coil stays clean and clog free.
- Install ultra violet lights next to the cooling coils to kill any mold or bacteria growing on the coils or collection pan.
- Keep your ductwork clean and use a high-efficiency filtration system to keep your entire HVAC system clean.
What does SEER, AFUE, and HSPF ratings mean to me?
SEER, AFUE and HSPF are all measures of energy efficiency. Air conditioners may look similar, but their Seasonal Energy Efficiency Rating (SEER) can vary widely. Higher SEER numbers save more money spent on electricity. A 13 SEER air conditioner, the EPA "current minimum standard", uses 23% less energy than a 10 SEER unit (EPA standard up until Jan. 2006). Even though 13 SEER is the minimum efficiency available, we currently offer a line of air conditioners that start at 13 SEER and go all the way up to a 21 SEER . Depending on your average usage, higher SEER air conditioners can significantly reduce your electric bill.
Heat pumps have SEER ratings like air conditioners and Heating Seasonal Performance Factor (HSPF) ratings for measuring heating efficiency. Higher HSPF ratings mean greater energy savings. The HSPF scale range is 7.5 to 13.0.
Today's new high-efficiency furnaces can save up to 50% in operating costs over a ten-year-old furnace. Many 1990 and earlier model furnaces have Annual Fuel Utilization Efficiency (AFUE) ratings of 65% or less. The minimum AFUE rated furnace that can be sold in the United States as of May 1, 2013 is 80% in southern states and 90% in northern states.
Our current product offering starts at this minimum AFUE rating and goes all the way to a very efficient 98.3% AFUE rating. Depending on your average usage, higher AFUE rated furnaces can significantly reduce your gas bill.
How can I reduce my energy costs?
- Upgrade to a high-efficiency air conditioner - Swapping your old, inefficient air conditioning system for a high-efficient one can cut electricity bills by one-third. Consult one of our professional technicians to ensure your system is the right size for your home, and you aren't over- or under-cooling for your space needs.
- Turn up the temperature — To save electricity during the summer, set the temperature above 75° as every degree below this will add an extra three to five percent to your energy bill.
- Install ceiling fans — Change the direction of airflow on your ceiling fans. In the summer, the blades should operate in a counter-clockwise direction as a way of creating a nice, gentle wind.
- Have an annual maintenance performed — Having an annual maintenance performed on your air conditioner by a licensed technician will help ensure it operates at its peak efficiency and catches any potential breakdowns before they occur.
- Don't block vents in well-used rooms — Keep your supply and return air vents free of objects like blinds, carpets or furniture so your air conditioner can operate efficiently and there is even cool air distribution.
- Upgrade to a high-efficiency furnace — New high-efficiency furnaces use up to 50% less fuel than an older system. It can save you up to 25 percent of your home-heating costs in one year, and within a few years, you'll have recovered the initial cost of replacing/upgrading your furnace. Choosing a model with an energy efficient motor can save 20 to 50 percent of the energy needed to continuously operate a fan motor. Let us show you the advantages of replacing your old furnace today.
- Have an annual maintenance performed — Having an annual maintenance performed on your furnace by a licensed technician will help ensure it operates at its peak efficiency and catches any potential breakdowns before they occur.
- Install a programmable thermostat — A programmable thermostat enables you to control your home's temperature when you're away or asleep. For every 1° you lower your thermostat for seven hours per day, you save one percent on your heating bill.
- Don't block vents in well-used rooms — Keep your supply and return air vents free of objects like blinds, carpets or furniture so your furnace can operate efficiently and there is even heat distribution.
- Install ceiling fans — Change the direction of airflow on your ceiling fans. In the winter, the blades should operate in a clockwise direction helping to push the warm air from the ceiling down into the room.
Why should I buy Energy Star labeled equipment?
The average home spends about $1,900 annually on energy bills. Heating and cooling accounts for as much as half of a home's energy use. The EPA provides important recommendations for energy-efficient equipment, including proper sizing, quality installation and maintenance, and other home improvement considerations to help you get the most out of the heating and cooling products you purchase, save energy, and save as much as 20% annually on your total energy costs.
ENERGY STAR qualified products prevent greenhouse gas emissions by meeting strict energy efficiency guidelines set by the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE).
What is a Heat Pump?
Heat pumps are a great solution for your home comfort system because they work to provide both heating and cooling. Heat pumps have SEER ratings like air conditioners and Heating Seasonal Performance Factor (HSPF) ratings for measuring heating efficiency. Higher SEER and HSPF ratings mean greater energy savings.
Heat pumps are a very efficient alternative to electric heat. A heat pump works the same as an air conditioner in the summer, but it runs in reverse in the winter to heat your home. The system will be matched with a backup heating source, most often electric heat for those extremely cold days of winter.
What is a Hybrid Heat Dual Fuel system?
With a traditional heating and cooling system, if you wanted to save more, you had to use less. But a Hybrid Heat system combines the benefits of intelligent control for both gas and electric heating to create an intuitive system that can actually react to changing conditions.
No matter what the temperature is outside, a Hybrid Heat system will automatically select the fuel source most efficient for your home, which means you'll stay warm in the winter, cool in the summer and save money all year long.
To design a Hybrid Heat system for your home, we professionally match one of our heat pump units with a natural gas furnace. Contact us to see how much energy you can save over your existing system.
What are the advantages of equipment with variable speed fans?
Variable speed fans operate on a simple principle: they are able to spin at different speeds depending on the heating and cooling needs of your home. Usually, they operate at lower speeds, delivering a steady, reliable stream of warm or cool air to your home. This helps control humidity levels, utility costs and system noise. When conditions become more extreme, the fan speed increases so that the system can meet increased demand, guaranteeing that on even the hottest days or coldest nights, you're comfort needs will be met.
How does 2-Stage heating or cooling work?
2-stage cooling is a method of cooling that can better manage the cooling of your home while outdoor temperatures are changing. It can also better maximize indoor comfort and energy efficiency. 2-stage cooling systems are typically the most energy efficient systems out there.
2-stage cooling can be done by having one unit with two compressors, one small and one large. The small one is typically capable of putting out about 50% the capacity of the larger one. The second way to have 2-stage cooling is to have a single scroll unloading compressor. This compressor can unload its capacity down to about 66% of maximum capacity. Both these methods of getting 2-stage cooling allow the unit to run at a lower stage when the high stage is not needed. By doing this, energy is saved.
2-stage heating has the same principle as 2-stage cooling. It allows the unit to adjust itself based on the amount of heating that is necessary. 2-stage heating is a good way to save on heating costs.
A heat pump system would have two different sized compressors, a small and a large one. The compressor that is used at a given time would depend upon the need. If only a small amount of heating is necessary, the smaller compressor would be used to save energy. The large compressor would only be used when a large amount of heating was needed.
A gas furnace that is 2-stage has a modulating gas valve that regulates gas flow depending upon the need.
At what temperature should I set my thermostat?
Normal cooling settings are 75 degrees - 80 degrees. Normal heating settings are 68 degrees - 72 degrees. You should always set your thermostat to the highest possible setting that is comfortable for you in the summer, and the lowest comfortable setting in the winter. Setting your thermostat in this way will maximize your energy savings. On average, every 1 degree of temperature change is equal to about 1% energy savings. For example, changing your thermostat setting from 75 degrees to 76 degrees in the summer could result in savings on your cooling costs.
My system doesn't work well in a couple of rooms, what should I do?
This can occur for many reasons; uneven solar heat load through windows, an undersized system, improperly balanced or clogged system or a single system serving a two-story home with no zoning control. Each situation is different, usually requiring an onsite analysis with problem specific recommendations. Please call to arrange for us to see your home.
Is Freon as a refrigerant being discontinued?
Yes. As of January 2010 the refrigerant R-22 (what consumers call Freon®) is no longer allowed to be used in the manufacturing of new equipment. R-22 has been used as the "standard" refrigerant for many years but has been found to be harmful to our planet by our government. All new air conditioners and heat pumps use R-410A, the more "environmentally sound" refrigerant.
R-22 is still the most commonly used refrigerant in existing air conditioning equipment in residential homes today. However, per the Montreal Protocol, caps have been established to eliminate the production of R-22. In 2004, there was a 35% reduction; in 2010 there was a 65% reduction; in 2015 a 90% reduction; and finally in 2020 a 99.5% reduction in the production of R-22. This means that during the time of these reductions with high demand, the price of each pound of R-22 refrigerant could potentially skyrocket.
If you are considering replacing your existing air conditioning equipment, most higher efficiency products have already made the switch to R-410A, the more "environmentally sound" refrigerant.
My air conditioner is very loud when I entertain outside, what can I do?
A difference of 6 decibels (such as between 72 dB and 78 dB) is technically a four-fold increase in compressor sound when rating air conditioners or heat pump units. However, it takes a difference of 10 decibels to double the loudness. It is also noted that it takes approximately 3 decibels for the average human ear to discern any difference in loudness at all.
Great strides have been made in reducing the operating sound level of equipment. We will be happy to show you the difference in sound ratings with our product line.
Can carbon monoxide build up in my home?
Yes. Each year, carbon monoxide kills more than 200 Americans and sends nearly 5,000 more to emergency rooms for treatment, reports the U.S. Consumer Product Safety Commission (CPSC). Where does it come from? When carbon-based fuels such as gas, oil, kerosene or wood burn, they produce gases. When fuel combustion or burning isn't complete, carbon monoxide enters the air. The CPSC advises that carbon monoxide detectors are the only way to alert yourself to the presence of toxic gas in your home. If you wake in the night with a headache -- and especially if another member of the family complains of a headache or is difficult to arouse -- get out of the house fast and seek medical help. We recommend carbon monoxide detectors be installed in your home!
What if I smell gas?
If you smell propane (LP) gas:
- Exit your home immediately.
- Propane gas can ignite easily. Do not light a match, start an engine, use a cell phone, or do anything that may create a spark.
- From a safe area, contact your propane supplier and call 911.
- If you are able, shut the propane gas supply off at the tank.
- Stay away from your home until you've been told that it is safe to return.
Natural gas: You have this type if you have a gas meter and pay a natural gas supplier or utility. A chemical odorant has been added to natural gas to give it a distinct smell. Learn to identify this odor.
If you smell natural gas:
- Exit your home immediately.
- Do not light a match, start an engine, use a cell phone, or do anything that may create a spark.
- From a safe area, contact your gas company or call 911.
- If you are able, turn the gas off at the meter.
- Stay away from your home until you've been told that it is safe to return.
Water Heater FAQ's
What does the Energy Factor (EF) on my water heater mean?
The water heater Energy Factor (EF) is a measure of the overall efficiency of the water heater. This is determined by comparing the energy in the heated water used daily to the total daily energy consumption of the water heater. The EF can be used to compare the energy efficiency of water heaters. Water heaters with higher EFs will have lower annual operating costs than comparable models with lower EFs. A higher EF signifies a more efficient model. Water heaters with high EF ratings may cost more initially, but save energy and money in the long run. Eventually, they will pay for themselves through a lifetime of energy savings.
Where is the 'anode rod' and what does it do?
For most water heaters, the anode rod is attached to the hot water outlet of the water heater. If you are facing the front of the water heater (where the labels are), the hot water outlet is on the left hand side. The anode rod is often referred to as a "sacrificial rod".
Most water is rarely "pure". It can contain oxygen, magnesium, fluoride, chlorine and suspended particles. These components, in the concentrations in your water, are usually not bad for you. However, they do contribute to the taste and smell of the water. They also impart a slight conductivity to the water. Through an electrical process called electrolysis, this conductivity will eventually (over a long period of time) cause most metal to rust or corrode. When the water is heated, this electrical process can be accelerated.
Most water heaters are made of a steel tank with a porcelain enamel (glass) lining. However, due to production and assembly methods, it is not always possible to completely cover the inside of the tank. Therefore it is important to provide metal that can be consumed by the electrical process. This is where the sacrificial anode rod comes in. By acting as a lightning rod for the corrosion process, the anode rod draws the harmful electrolytic process away from the water heater tank and focuses the corrosion on the anode rod. Water heaters need this sacrificial anode rod to ensure that the electrolysis does not affect the tanks.
Why doesn't my old water heater make as much hot water as it used to?
The answer may be that you have sediment buildup in your tank. As water heaters age, they tend to accumulate sediment and lime deposits. If the heaters are not cleaned periodically, the sediment may rise to a level that will act as a barrier between the burner and the water, making it harder to heat. An article published in a national ASPE plumbing journal states: for every half inch of sediment on the bottom of a gas fired water heater, it requires up to 70% more fuel to heat the water.
If my water heater was in a flood, do I need to replace it?
Yes. The Air-Conditioning, Heating and Refrigeration Institute (AHRI) recommends that any flood-damaged heating and cooling equipment be replaced, not repaired. From the AHRI website, as it pertains to water heaters:
"Whether your water heater is gas-fired, oil-fired or electric, if it was exposed to flood water, the unit should be replaced.
In a gas unit, valves and controls will likely corrode. In an electric unit, the thermostat and controls will likely corrode. In both types, the insulation surrounding the unit will be contaminated and will be nearly impossible to disinfect. Additionally, the insulation would take a long time to dry, leading to corrosion of the tank from the outside.
Even if water heater components have been cleaned and the unit seems to operate properly, parts may corrode in the future. Both gas and electric water heaters have a pressure relief valve that can corrode and stick after being exposed to flood water. Therefore, be sure to replace this valve as well."
(Taken from www.ahrinet.org)
At the suggestion of AHRI, be sure to have your inspection and replacement work performed by a qualified professional.
Can I use my water heater with a solar heating system?
With the increasing costs of energy and a desire for environmental friendliness, some customers are turning to the sun as a way to heat their domestic water. Bradford White manufactures a solar water heating storage tank for use with solar systems. This tank takes the heated water from the solar panels and uses it as a heat source instead of conventional gas, oil or electric heat sources unlike other tanks, this water heater has an electric heating element for back up on cloudy days, and when the solar system is not providing enough heat. However, it is important that you use only POTABLE (or domestic use) water in this tank.
Is a drain pan necessary?
A water heater should be placed in an area that will prevent damage to floors, ceilings, and furniture if the heater leaks. When this is not possible, a drain pan must be installed under the water heater. Since a typical drain pan doesn't hold that much water, it must have a pipe to a drain or other outlet for the water. When installed properly, a drain pan and pipe will keep any leakage under control and protect your belongings from water damage.
What type of maintenance should I do on my water heater?
We recommend that you contact a plumbing professional to perform any maintenance or repairs to your water heater - from periodic checks on the anode rod to ensuring that all connections are secure. Recommendations for maintenance are in your water heater's owner manual. However, there are a few things that you can do:
- Ensure that there are no sources of flammable vapors in the same area as your water heater (this includes gasoline, heating oils, lighter fluid, propane, etc.).
- Keep the top of the water heater clean. If you notice water dripping on the water heater from any piping, contact a plumbing professional to have the leak repaired.
- Keep the space around your water heater clean and free of dirt, boxes, paint cans, aerosol cans, household cleaners and trash. It is important to keep the heater accessible for proper operation and easy maintenance.