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Author: Kevin

Which HVAC Brand is Best?

We’ve been in the business almost 20 years now and have installed and serviced a variety of HVAC units. We are not paid by manufacturers to promote their brand(s); instead, we recommend brands based on our vast experience and our customer’s individual needs.  If the customer has a preference for a certain brand, we do our best to provide it.  But, if you really want to know which brand is best, here are the facts:

The Dirty Little Secret

When you look beyond the label slapped on the outside of the unit, you’ll see that most of the internal components are the same.  There are about six HVAC equipment manufacturers in the U.S. who make about 150 different brand names.  Many of them use the same internal components and are produced on the same assembly line in the same factory.  Goodman and Amana are made in the same factory, yet Amana typically costs more.  Carrier, Bryant, Payne, Tempstar, and Day and Night are made in the same factory, yet Carrier has more name recognition due to more advertising.  York and Luxaire are both owned by Johnson Controls.  There’s almost no difference between Trane and American Standard.  Lennox, Ducane, and Concord are all made by Lennox.  Even less obvious is that some of the internal components of all brands are made by just a handful of third-party companies, making many components interchangeable between brands.  With so much the same, what’s the real differentiator?

The Real Differentiator

Unlike many other products, when you purchase an HVAC system, much of the design and engineering occurs on-site (at your home).  Each home is different and presents different challenges with ductwork, physical location, clearances, etc.  No brand, no matter how much it cost and its reputation, will perform reliably if not installed and maintained correctly.

The overwhelming majority of HVAC failures are the result of improper installation or maintenance.  In fact, a good percentage of our business comes from people who hired the cheapest contractor to install their unit, or who think they saved money by not having regular spring and fall maintenance.  There’s a proper way to install and maintain an HVAC unit and it’s worth paying for that expertise, because going with the lowest bid can often cost you later.

Just as not all doctors, mechanics, or hair stylists are the same, neither are all HVAC contractors.  Sometimes, it’s worth going a bit out of your way, or waiting an extra day for an appointment to get a professional you trust.

Pitfalls to Watch For

Watch out for contractors who:

  • will offer you a great deal on a discontinued model,
  • do not provide continuing education for their technicians or use transient laborers,
  • don’t inspect your existing ductwork (if it’s a replacement) or will quote you a price over the phone,
  • won’t be around to honor the service agreement you purchased.

At Interstate AC Service, we use only qualified, licensed HVAC service technicians, we never use undocumented workers, we provide continuing education to our technicians, our technicians are not paid on commission, and we are committed to customer service.

Buyer Beware!

Don’t be fooled by a system that says it will last for 20 years.  Not without regular maintenance it won’t!   If you neglect your system, it won’t matter what brand you buy!  Here are some other things to watch for:

  1. Proprietary Design:  With some brands, the parts may be proprietary and not interchangeable.  So, there may be longer wait times for replacement parts because you can only get them from one manufacturer, and it may make the unit more expensive or difficult to maintain over time.
  2. Specifications:  When comparing units, be sure you’re comparing apples to apples.  Comparing a SEER 14 unit to a SEER 21 unit is not valid, because each is built to different specifications and their cost to operate varies widely.  Be aware that not all manufacturers offer units with the same SEER rating (Don’t know what a SEER is? Check out our post What’s Your SEER?).
  3. Features:  Look at the extras that may be rolled into the price.  Is part of what you’re paying for the extended warranty?  A bigger thermostat screen might not be worth paying extra for, but a quieter unit may be… only YOU can determine what features are of value to YOU.
  4. Reviews:  Few people will go online to write something positive about an air conditioner, heat pump, or furnace.  It’s only when it doesn’t work that people typically feel compelled to write a review.  Keep in mind when reading reviews, you cannot know reliably what the circumstances were.  Most failures are not due to the workmanship inside the unit but to the faulty installation and maintenance.  Did the installer install a mismatched AC condenser and evaporator?  Was the unit maintained under a service contract the entire time?  Take the reviews online with a grain of salt!
  5. Allegiances: Use an impartial contractor – one that is licensed to install and service all major brands.  A “factory-authorized dealer” for a single brand can only offer you the prices and features of that brand, even if that might not be best for your needs.  Not having a vested interest in one particular brand means you’ll have more options. [Note: Interstate AC Service is licensed to install and service all major brands – both residential and commercial.]

Bottom Line

The most important aspect of your HVAC system is not the brand you choose, but the contractor!  Except for minor differences, all brands are fairly comparable, but it’s the installation and service that matters.  Unfortunately, buying a “top” brand (one you’ve heard of or has good reviews) doesn’t matter much when it comes to HVAC units.

If you live in the Nashville or surrounding area, and need help with an HVAC issue at your home or business, know you can call on Interstate AC service at (615) 832-8500.  We’ll provide unbiased, professional service you can trust. We never forget we’re here for you!

Why is AC Capacity Measured in Tons? And What is a BTU?

When sizing up a new air conditioner, heat pump, or HVAC unit, it is common to hear the pros throw around terms involving tonnage, saying for example, you need a 3-ton or 4-ton unit.  For reference, 4 tons is about the weight of an adult elephant!  But don’t be alarmed: they’re not talking about the weight of the unit!  This is a throw-back from the 1800’s and the term stuck.  You may also hear pros refer to the capacity of HVAC units in terms of BTUs.  Did you know these terms are related?  Here’s how they originated:

Historical Perspective

Before the modern air conditioner was invented, people used to cool buildings in the summertime using ice harvested from rivers and lakes. Gathering the ice from farther and farther north and shipping it down south, or storing it from winter until summer, meant a lot of ice was lost to melting.  A BTU, which stands for British Thermal Unit, is the amount of heat required to raise 1 pound of liquid water 1 degree.  But, when water is below freezing (less than 32 degrees Fahrenheit), the amount of heat needed to melt ice is 143 BTUs per pound.

How the Math Works Out

A ton weighs 2,000 pounds, so to melt a ton of ice it takes (143 BTU/lb) x (2,000 lbs) = 286,000 BTUs.  How quickly the ice will melt depends on how quickly you heat it.  If you apply the heat uniformly over a 24 hour period, the ice will have absorbed (286,00 BTU) / (24 hours) = 11,917 BTUs per hour.  That number is generally rounded up to 12,000 BTU/hr.  So, a one ton air conditioning unit has the capacity to cool up to 12,000 BTU/hr.

Sizing an AC Unit for Your Home

When comparing costs of different HVAC units, be sure you are comparing similarly-sized units.  Central air conditioning units frequently have the capacity coded into the model number: for example, model RDR36 would be a 36,000 BTU unit, or expressed in tonnage – with 12,000 BTUs being the heat needed to melt 1 ton of ice – the model RDR36 would be a 3-ton unit (= 36,000 / 12,000).

Multiple Factors Affect Sizing

If you have a 2100 sq.ft. home, a 2-ton heat pump will not be adequate; you’ll need maybe a 3.5 or 4 ton unit. Here’s where having a professional who can do a site visit helps. There are many things that contribute to sizing an HVAC system, other than the number of square feet you want to cool.  Here are just a few:

  • How well the house is insulated and when it was built
  • The numbers and sizes of the windows and doors in the house
  • The color of the roof: darker ones absorb more heat
  • The height of the ceilings
  • The overall shape of the home: long narrow houses lose more heat (through walls) than a more square house of the same size.
  • The size of AC’s condenser, and whether it is positioned in the shade or in the sun
  • The efficiency of the cooling unit, often expressed as a SEER rating, or seasonal energy efficiency ratio (see our post What’s Your SEER?).

Moral of the Story

Knowing the number of BTUs that will be required to heat and cool your house effectively is not only important in choosing the right size furnace and air conditioning system, but it can also tell you whether your existing system may be too large or too small… yes, a system that is too large will not cool effectively, so bigger is not always better! (read our post Think Bigger is Better?)  Now that you know that tonnage does not refer to the weight of the unit, and how to convert from tons to BTUs, you can more readily compare units. Proving yet again that knowledge is power!

If you live in the Nashville and surrounding area, and need some help figuring out the right BTUs and tons for your home, we’ll be happy to help.  Plus, if you haven’t had your spring tune-up yet, now’s the best time!  Call on us at 615-802-2665.

10 Ways to Make Use of Passive Solar

Harnessing solar energy does not mean you need photovoltaic panels on your roof and technological solutions.  There are many ways to design passive solar into a home that will allow you to lower your heating and cooling costs year-round, and make your home more environmentally friendly.

What is Passive Solar?

Passive solar means using the building’s windows, walls, and floors to collect, store and distribute solar energy in the form of heat in the winter, and rejecting solar energy (heat) in the summer.  It is called “passive” because it does not use mechanical means to distribute heat, but rather takes advantage of natural convection, radiation, and air flow.

Is it worth it?

If you’re adding energy-efficient features into an older home (built before 1993) that currently has little insulation, less energy-efficient windows, and non-EnergyStar appliances, you may be able to reduce heating and cooling costs by up to 50-60%.  That savings will pay for itself year after year, and many of the passive solar design features also add aesthetically to the house and increase the house’s market value (see “Going Green Can Add Value to Your Home”).

10 Ways To Incoprporate Passive Solar

If you are not building a new home from scratch, you may not be able to take advantage of all of the suggestions below, but, the more you can do, the more you’ll save.

  1. Use wide overhangs on your house to shield the house from the sun in summer. Western or eastern-facing windows are particularly vulnerable to overheating in summer, so these should be shaded using overhangs and large leaf-bearing shade trees that shed their leaves in the fall.
  2. Have south-facing windows that have an unobstructed view of the sun (no big trees or tall buildings in the way).  Keep these windows clean and keep the drapes, blinds, or shutters open during the cooler months while the sun is shining.  In the warmer months, place a removable reflective film on these windows or keep the drapes, blinds or shutters closed to block the sun.  Remember: if light can get in, so can radiant heat.
  3. Capture and store the sun’s heat in thermal masses inside the house.  This can be concrete, brick, stone, or tile which is used on walls or floors.  The thermal mass absorbs heat from sunlight during the heating season, and absorbs heat from the air during cooling season.  You can easily create a thermal mass by having a brick or stone fireplace which extends up the entire wall, or adding tile or decorative concrete flooring in the room containing the best sun exposure.
  4. Take advantage of the “chimney effect” (natural convection). Since heat rises, install operable skylights (skylights that open) in the upper-most areas of the house, such as an upper floor or vaulted ceiling.
  5. Use clerestory and transom windows or light tubes to let natural light in year-round, so you minimize the use of electric lights. Convert all lights in the house to LED bulbs, which radiate far less heat.
  6. An open floor plan takes advantage of passive solar the best, as do open stairwells and atria.
  7. Install EnergyStar-certified appliances and fans throughout the home, and energy-efficient double or triple glazed windows. Casement windows offer the best air flow.
  8. Add insulation to your attic.  This will help year-round (see our post “5 of the Best HVAC Investments You Can Make”).
  9. Make your roof reflective with a light color paint, or by using reflective paint, shingles, or tiles. Roofs receive the majority of solar radiation delivered to a house, so a cool roof will dramatically cut air-conditioning bills.
  10. Allow the landscape design to work in your favor. Use evergreen hedges and shrubs as windbreaks. Use deciduous trees (trees that drop their leaves in fall) near the house, to provide shade in summer and allow light in in winter.

The real joy comes in living in an energy-efficient, eco-friendly, passive solar house that is not only beautiful, but saves you money every single day.

If you live in the Nashville or surrounding area, Interstate AC Service can help with all your heating and cooling needs.  Call on us at 615-802-2665.  We’re here for you!

Be Pro-Active With an Off-Season Replacement

It’s no surprise that the demand for air-conditioners is highest in the summer, and the demand for furnaces is highest in the winter.  If you have an old or failing HVAC system, it will likely go out when it is stressed the most – on the coldest or hottest day of the year – when the demand is greatest.  Well, that’s when everyone else is calling for service, too!  So you may find, no matter what HVAC company you call, they won’t be able to get to you right away.  [If you’ve ever had the unfortunate experience of needing a tow truck after slipping on snowy/icy roads, you know what I mean!]

Be Pro-Active!

The best time to get a new furnace is in the spring and summer, and the best time to get a new air-conditioner is in the fall and winter.  Of course, if you’re replacing an entire system – like a heat-pump that is used for both heat and air – then the best time is during the “in-between” seasons – spring and fall – when systems are less stressed and the HVAC companies are not overrun with service calls.

Benefits of Being Pro-Active

Being pro-active has many added benefits:

  1. You may get off-season discounts or manufacturers’ rebates.  Plus, you’ll have time to get a professional analysis done of your home, get 2 or 3 quotes, and do research on the companies.  You won’t be in a “desperate” situation: like having no air conditioning on a day with 90+ degree temperatures and 90% humidity!
  2. It’s less disruptive for the homeowner.  You can schedule the install at a convenient time for you, and you won’t have to worry about being down (without heat or air) when it’s most needed!  Face it: it’s much less of an “inconvenience” to be without heat or air (while your old system is being removed and your new system is being installed) when it’s not freezing cold or blazing hot out!
  3. It gives you time to research the various kinds of systems, and the various features, to find the one best for you.  When it’s 7 degrees out and you’ve been without heat for 12 hours, you’re not going to be in much of a “shopping” mood and may wind up getting whatever is readily available and can be installed quickly, rather than the best system to meet your needs.

Think Spring!

If you know your HVAC system won’t stand another winter or summer… don’t just let it slip your mind as we approach spring.  That’s when you SHOULD be thinking: now’s the best time to replace it!  Remember, the best time to buy a new system is before your existing system fails, and before the extreme hot or cold weather arrives.

If you need heating or air-conditioning service, no matter the season, call on Interstate AC Service at 615-802-2665.  We’re here to provide all of Nashville and surrounding areas with professional , dependable HVAC system service and installation.

HVAC Iced Up?

One of the common problems we encounter is a heat pump that has iced up.  A heat pump in good condition should be able to operate in below freezing temperatures without icing over, so why does this happen?

Things to Eliminate

Here are some circumstances that cause icing which you may be able check, fix or eliminate:

  1. Check to make sure the outdoor unit is not blocked by leaves or covered in any way.  Some people mistakenly think that covering the outdoor unit helps protect it from bad weather in the winter, but this is dead wrong. It always needs proper airflow around it.
  2. Check to make sure you do not have water dripping into the unit by a leaking or blocked gutter.  As temperatures drop, that water will harden into ice and could cause the fan blades to cease up.
  3. Check to make sure there is room for water to drain away from the unit… that it hasn’t sunken into the ground.  If water pools around the unit, it will freeze as temperatures fall, and the ice will impede the operation of the unit.
  4. Check to make sure that nothing is restricting airflow inside the house, such as dirty filters or blocked vents.

If you’ve eliminated these as possible sources of the problem, then it could be a mechanical or electrical problem inside the unit itself.  First, let’s look at how a heat pump should work.

How Heat Pumps Work

The refrigerant inside the heat pump transfers heat back and forth as needed. Even in the winter, there is heat that can be extracted from the outside air to help heat the inside of your home.  But to do so, the refrigerant needs to get very cold… much colder than the outside temperature.  When coils get this cold, water vapor in the air will start to crystalize into ice around them. To prevent ice build-up, the heat pump will periodically go into a defrost mode.  A valve switches so that the outdoor evaporator becomes the condenser.  This allows the coils to get warm enough to melt any ice that may have formed.  While in defrost cycle, the fan turns off so you won’t get cold air blowing on you, or a second-stage heater comes on to offset this cold air.  After the outdoor unit reaches a certain temperature, or after a certain amount of time goes by, the valve switches back and the system returns to normal heating mode, reversing the evaporator and condenser. This cycling on and off happens transparently to the user while the heat pump is in use.

Reasons Heat Pumps Ice Up

  1. Perhaps the most common reason heat pumps ice up, is that the reversing valve gets stuck.  This prevents the heat pump from going into its defrost cycle and the ice on the outdoor coils continues to accumulate until it impedes the turning of the fan blades.
  2. If the reversing valve is fine, it could be that something is wrong with the defrost timer, sensor, or control module, so that the defrost cycle is not completing or not happening often enough or not being triggered at all due to a faulty thermostat or sensor.
  3. If the system is low on refrigerant or the outdoor fan motor dies, this could also cause the system to ice up.

Each of these reasons will likely necessitate a service call.

In the Meantime…

If you can visually see your outdoor unit has iced over, turn the unit off.  If you are able to, turn on the emergency heat mode until help can arrive.  Do not continue trying to run the unit “normally” as this will only cause more damage, and don’t wait too long before seeking help, as this may increase the extent of repairs that are necessary.  Do not try to pick off the ice with a sharp object, as the coil and fins will damage very easily, and you may cause a refrigerant leak.

Prevention

As with most HVAC systems, problems with a heat pump can often be prevented with proper maintenance.  Getting a fall maintenance check before the worst of the cold weather sets in, and getting a spring maintenance check before the heat of the summer, will help lessen the probability that you’ll find yourself all iced up!

If your HVAC system needs attention and you live in the Nashville area, call on Interstate AC Service at 615-802-2665.  We’re here for you.

HELP! My Heat is Blowing Cold Air!

We’ll frequently encounter a caller complaining about their heating system blowing cold air.  We may ask a few other questions but it comes down to this: what temperature is the thermostat set to and what temperature is it reading in the house?  The answer to those questions can often expose the problem without a service call.

Gas Furnace vs Electric Heat Pump

Suppose the caller tells us that the thermostat is set to 70 degrees and the room temperature is reading around 70 as well, but they still feel cold air blowing from the system.  This is often a clue that this homeowner is experiencing their first winter with a heat pump instead of a furnace – in other words, electric heat rather than gas heat.  Here’s the real issue: Gas heat is much hotter coming out of the vents than electric heat.  A gas furnace puts out 130 to 140 degree air.   In contrast, a heat pump may only put out air at about 85-92 degrees. But regardless of the heat source, both types of heating systems are able to maintain the inside house temperature at 70 degrees.  Our body temperature is normally 98.6 degrees.  Gas heat puts out air that is much hotter than our body temperature, so it feels warm.  Electric heat puts out air lower than our body temperature, so by comparison, it feels cold.  Additionally, because gas heat puts out hotter air, it does not need to blow as hard or as long as electric heat to achieve the same room temperature.  Frequent blowing causes evaporation from the skin which naturally cools the body, and may make us feel chilled.  So, if this is your first winter with a heat pump, and the air temperature is keeping close to what whatever you’ve set the thermostat to, there likely is no problem with your heating unit.  It just might take some getting used to.

Switch Fan to AUTO

Here’s another possibility:  Remember how we said blowing air helps cool you?  In the summertime, it is often helpful to turn the fan setting on your thermostat to “On” – so it runs all the time – rather than “Auto” – where it only blows when the unit kicks on.  But in the winter, you’ll want to set the fan back to “Auto”.  Just like on a windy day, blowing air makes us feel colder than the actual air temperature.  In between the heat cycling on, the air inside the ducts may cool below the “usual” heated air temperature, so if the fan is on all the time, it will be blowing cooler air at you until the heating unit kicks back on.  Avoid a service call by just manually switching the fan setting on your thermostat to “Auto” in the winter.

Service Call? Things You Can Check

But, if the room air temperature is really well below the thermostat setting, then you may indeed have a problem!  The outdoor unit may have iced up, or your system may have a bad reversing value or compressor, or the refrigerant may be low (yes, you still need refrigerant for heat!).  Any one of those things will likely require a service call.  But here are some things you can check and might be able to fix yourself.  Is the thermostat switched to cool mode instead of heat mode?  Turn it off, and then flip it to heat mode.  If your ductwork goes through an attic, crawl space or basement, are there open windows in those areas?  Does the ductwork have a hole in it or has it become separated from the main trunk?  Those things will need to be fixed before it’s possible to determine whether there is an actual mechanical problem with your heating system.

Not As Warm As You’d Like?

If you live in the Nashville or surrounding area, and your heating unit is not keeping you as warm as you’d like, give us a call at 615-802-2665. We’re here for you.

Don’t Throw Away Your Old Thermostat!

You’ve probably heard us talk about the benefits of using a programmable thermostat, or have read our head-to-head comparisons of the Nest and Honeywell smart thermostats. We’ve touted that swapping out your thermostat can be a do-it-yourself project, but, any time you replace a thermostat, you’re left with what to do with the old one.

Your first inclination is to place it in the trash – especially if the reason you’re replacing it is that it no longer functions.  STOP!  Did you know that thermostats contain hazardous mercury that can contaminate the environment and can be fatal?  While installing a new smart thermostat helps protect the environment, throwing your old thermostat in the trash does just the opposite!

Since the 1830’s, thermostats have contained mercury – a metal that is liquid at room temperature and gives off vapor if not contained.  The new electronic thermostats do not contain mercury.  Although mercury thermostats are the largest source of mercury in homes, other sources of mercury include CFL and fluorescent light bulbs, batteries, and thermometers.  But there is no concern with exposure to mercury inside these devices, as long as the mercury is contained.  The problem arises when you throw them into the trash: the trash goes through a compactor, and then is taken to a landfill, so it is likely that the mercury bulb within the thermostat will bust at some point, and the mercury will escape.  Mercury does not break down.  It gets into the ground water, our lakes and streams, fish and birds, and becomes concentrated in our food supply, and in people.

According to the World Health Organization, mercury exposure is a major public health concern.  It can result in neurological and behavioral issues, kidney toxicity, and digestive tract and lung issues.  In utero and in children, it affects development, language, memory, cognitive thinking, motor and spatial skills, and attention.  It can be fatal if inhaled or ingested.

Many states have already taken steps to ban mercury-containing thermostats from being sold or installed.  In most states, including TN, it is illegal to throw out thermostats in the trash.  Although mercury cannot be destroyed, it can be recycled and reused.  However, mercury-containing products cannot be recycled by simply throwing it in your curbside recycling container.  So, what should you do?

Place your old thermostat in a sealable container such as a ziplock bag or plastic tuperware container.  This is so that if the mercury bulb breaks inside the device, its vapors will not be breathed in.

Check online for the nearest hazardous materials drop-off site.

But the easiest thing to do is to give it to us or any HVAC contractor.  We are all obligated to recycle the thermostats for you.

So, next time you’re getting your Spring or Fall maintenance visit, give us your old thermostat.  Or better yet, call on us to install a new thermostat for you, and we’ll take your old one with us when we leave.

If you live in the Nashville and surrounding area, call on us at 615-802-2665. We’re here for all your heating and cooling needs.

DIY Heating Fixes

It always seems your heat will go out on the coldest day of the year!  Why spend money when you may be able to fix it yourself? This post describes some trouble-shooting and fixes you may be able to do before calling a technician.

1.   Thermostat-related issues:

  • Is the display on your thermostat blank? It could be because it needs a battery, or that the circuit breaker to it has been tripped or you’ve blown a fuse. Reset the tripped circuit breaker, replace the fuse, or replace the battery.
  • Make sure all the wires going to the thermostat are connected and not loose.
  • Check that the thermostat is in heat mode. This switch can easily get accidentally bumped while dusting.
  • For programmable thermostats, check that it is set to the correct day and time, including the AM or PM designation.  One customer bought a programmable thermostat to save money, with the intent to have the heat backed down while the customer was away at work, and have the heat cranked up at night when the customer was home.  When the customer started freezing at night, they mistakenly thought something was wrong with their heat, when the real culprit was they had the AM/PM designation backwards on their thermostat!
  • If you had a recent power outage, it could be that all of the settings on your programmable thermostat have been wiped out.  Often there is a battery backup in these units, so you may need to change the battery and then re-enter your settings.

2.   Furnace-related issues:

  • If the heat is out and you do not hear the fan coming on, and there is no air coming out of the supply registers, there may be no power to the furnace.  This is often due to someone flipping the switch accidentally while cleaning out the attic or basement (areas where the furnace may reside). The switch often looks similar to a light switch and is easy to mistakenly turn off.  Just flip the switch back, and you should hear the furnace start up within 3-5 minutes.
  • Many thermostats get their power from the same electrical circuit that feeds the furnace system, so if your thermostat is blank, turning on the switch by the furnace may be the solution.
  • Some furnaces have emergency cut-off switches that are activated when a door or service panel is removed. If the furnace door is not closed properly (such as after a filter cleaning), or has been accidentally bumped open, the cut-off switch will prevent the furnace from coming on.  Verify all access doors are properly closed.
  • If the fan runs, but the air coming out is cold, you have a problem with the furnace (or heat pump) itself, and may need a service call. This may not be something you can tackle yourself.

3.   Electrical Issues:

  • If the switch is on to the furnace and it still doesn’t come on, it could be that the circuit breaker or fuse to the furnace (or heat pump) is tripped or blown.  Reset the breaker by turning it all the way OFF, then back ON. If the fuse for the furnace is blown, be sure to replace it with the same size and type of fuse.
  • If a breaker keeps tripping or a fuse keeps blowing, contact a qualified electrician to inspect your system to determine why you are having problems.

4.   Filter issues:

  • A dirty air filter restricts air flow, and the system will work harder and build up pressure. Some newer, more efficient furnaces are sensitive to this pressure build up and turn off before the dirty filter can cause further damage. At the very least, a dirty, clogged filter will reduce the heat output of your system. The simple solution is to change the filter!
  • Don’t try to just vacuum the existing filter and re-insert it. The material inside the filter will still be saturated. Just place the old filter in the trash and insert a new one each time… at least every 3 months.

If none of these DIY fixes addresses your problem, give us a call at 615-802-2665.  We’re always here to help!

Things to Consider When Buying A New Furnace

Heating equipment is one of a homeowner’s major expenses. The efficiency of your furnace can make a big difference in your energy bills. A new furnace will save money on your heating bills, be safer, and greener (better for the environment).  Our best advice is to plan ahead!  Don’t wait until the dead of winter and your heat has gone out to start thinking about replacements. In fact, you’re likely to get the best pricing on a furnace in the spring or fall.

Average Lifespan of a Furnace is 15 Years

Don’t know how old your furnace or heat pump is?  Open the cabinet and look for dates.  Write down the model number and search the Internet to find an approximate date of manufacture. If your furnace has a standing pilot light instead of electronic ignition, or its AFUE (Annualized Fuel Utilization Efficiency) rating is less than 80%, this is a sign that it is obsolete and wasting energy. If your heat pump has a HSPF (Heating Season Performance Factor) of less than 7.7, you should consider replacement. If you already know your existing furnace won’t make it through another winter, or you’re facing major repair bills on a furnace at least 15 years old, you should buy a new one now.

Types of Systems

Generally, you’d want a central heating solution, unless you are forced into a local heating solution due to not having any ductwork.  For a local solution, a mini-split system is ideal because it does not require ductwork and is extremely efficient (see our previous posts on mini-splits here: 1, 2, 3).  For central heating, you can go with a split or packaged system.  Split systems are most common, and have a condensing unit and coil that sits on top of your furnace.  They have an indoor component and an outdoor component, hence the term “split.”  Packaged units mean it’s all in one unit and that unit can sit outside.

What Fuel Type Is Best?

Natural gas is the least expensive way to heat. Oil or propane furnaces are an option only if your home does not have gas lines. Electric furnaces (heat pumps) are more efficient than natural gas, but producing heat from electricity is more expensive. A heat pump can also act as an air-conditioner in the summer, so can be used year-round.  If you have a natural gas furnace, you’ll still need another option for air-conditioning. Some systems are dual-fuel systems, which use a heat pump (electricity) to heat and cool your home, and a gas furnace which serves as the back-up heat source and helps deliver the heated air produced by the heat pump.

Size: How Large a System Should You Buy?

Don’t just blindly get the same size that was originally in the house, as additional space may have been added over the years. In order to size a system appropriately, a load calculation must be done, taking into consideration the square footage of the home, ceiling height, shade around the home, insulation, types of building materials, and the numbers and types of windows and doors. If you get a system that is too big or too small, it won’t work well (it won’t provide good temperature and humidity control), will not be efficient (you won’t see the fuel cost savings you’d expect from a new system), and will break down sooner.

Efficiency is the Key

Always go with the most efficient furnace you can afford, the one with the highest AFUE number (Annual Fuel Utilization Efficiency rating).  This is the number on the yellow “Energy Guide” label on the unit.  Just remember, the higher the AFUE, the lower your monthly heating costs.

Look for the ENERGY STAR® label and certification on the unit to be assured it will meet government efficiency standards. Other criteria to look for include:

  • A variable speed blower motor.  This will save energy and reduce noise.  A fixed-speed blower blows hot air into the house full force for a few minutes, then shuts off – often resulting in pockets of warmer and cooler areas.  A variable speed blower blows faster when it’s colder outside, and then slower for longer periods, providing quieter and more even, comfortable heat.
  • A sealed combustion chamber: this not only makes the system quieter and more efficient, but safer, too, as it avoids the possibility of introducing combustion gases into your home.
  • A second heat exchanger with condensing flue gases and/or 2-stage gas valves.

Installation: What to Expect

Installation takes about a day, but can take several days if your ductwork also needs to be replaced. Never compromise on installation quality.  A poor installation may mean the unit won’t perform at its potential and could cost you more to run. Be sure your new system is installed by a certified licensed HVAC contractor with a proven track record of successfully installing similar systems to yours.

A Good Time to Consider Options

Any time you’re considering a major replacement, may also be a good time to consider other options.  For example, installing a multi-zone system will allow you to control multiple areas of your home independently with separate thermostats without buying separate systems. Getting an electronic programmable thermostat will give you more precise control of temperature and could lower your energy bills by up to 30%.

Should you replace your heating and cooling systems at the same time?

In general, the answer is yes.  This is because mismatched systems may not deliver the energy efficiency or performance you expect, and could contribute to service problems later on. A central system uses the same ductwork for both heating and cooling so you want to be sure all parts work together.

Is Maintenance Necessary on a Brand New System?

Yes. But only if you want it to last a long time, not have unexpected breakdowns, maintain its efficiency and perform at peak levels. That way, you’ll know if there has been a recall or if a part is covered by warranty when it goes go out. Some warranties can be invalidated if you cannot prove the unit has been under a service contract.

Pricing

Do not make a decision based on upfront pricing alone.  Check to see if there are manufacturer’s rebates or incentives you can take advantage of, or low interest financing, or tax credits.  Having a reputable HVAC contractor is more important than the price.  You’ll want to feel confident the system will be sized appropriately, installed correctly, and that the company will be around to offer on-going maintenance and support. A longer warranty should also be factored in, as it can translate into cost savings in the long run.

Selecting a Contractor

You should get multiple bids from reputable, licensed, NATE-certified HVAC installers. Make sure they inspect your home and be wary if they give you an estimate over the phone.  Get the estimate in writing and understand what’s included.  Ask about warranties and service agreements. Remember the best value may not come from the contractor with the lowest price.

Now’s the time to focus on energy improvements in your home! If you live in the Nashville or surround area, give us a call at: 615-802-2665. Interstate AC Service will help you with all your heating and cooling needs.

Extending Your HVAC’s Life – True Stories

We all try to make our dollars go farther and last longer.  Big expenditures – like a new HVAC system or a major HVAC repair – can break the budget… and who has time for that anyway?  Here are some true stories from customer experiences we can all learn from.

Case #1:  A married couple, Dan & Cheryl, decided to sell their house their 18-year-old house.  The buyers were apprehensive about the original HVAC unit, and figured it would never pass inspection… in fact, they were hoping to use the aged HVAC unit as a bargaining chip to force concessions from the owners.  To the buyer’s and inspector’s surprise, this 18-year-old HVAC passed inspection with a totally clean bill of health!  Here’s what Dan & Cheryl did, and you can, too!

  1. Get regular fall and spring tune-ups.  This will help keep your system running like new, increase efficiencies and keep your daily heating and cooling expenses low.  Plus it will spot problems when they can be easily fixed, before causing a major outage.  For both time and money, having regular system maintenance can only work in your favor.
  1. Change your air filters regularly.  Set automated reminders and never use a filter longer than 3 months.  Never try to just vacuum the filter and reuse it!  The microscopic debris imbedded deep inside the filter can harm your system over time. During every filter change, clean out the return air ducts and grill with a cloth or vacuum, too.
  1. Keep the air vents open and clean. Never block vents with magnetic covers, furniture, or anything that would impede airflow.  This causes extra strain on the HVAC unit.  During fall and spring house cleaning, clean out the vents using a cloth or vacuum to remove any dust or debris.  To see how, check out a previous video we did illustrating this.
  1. Keep the indoor and outdoor units free of debris.  This means cleaning off the leaves throughout the fall, keeping grass clippings out of the unit, and keeping the area around the inside and outside units free of obstructions.
  1. Add a whole-house electronic air cleaner.  This helps keep the heat exchanger free from debris which over time causes cracks, leaks, expensive repairs, and could even cause carbon monoxide poisoning.

Case #2:  Now, let’s look at the experiences of another homeowner named Sherrie.  She rented out her home for a year prior to selling it. At that time the renters moved in, the HVAC unit was just 8-years-old.  A year later, Sherrie was in for surprise!  The renters had not changed the HVAC filters at all during the entire years’ time, and it had burned up the HVAC unit to where it would no longer come on.  They also had not kept up the maintenance on this heavily wooded lot, and the HVAC unit was covered in debris.  Sherrie had to pay nearly $8,000 for a new HVAC unit before it could pass inspection, thus taking a big chunk out of her sales’ profits.  Ouch!  That is a hard way to learn that the most important thing anyone can do to prolong the life of their HVAC unit is to change the air filters!

Whether you’re getting ready to sell your house and don’t want to be faced with a failed inspection – or you’re  a conscientious homeowner, looking to make the best use of your time and money, following these steps will help prolong the life of your HVAC system.

If you live in the Nashville or surrounding area, rely on Interstate AC Service for all your HVAC maintenance needs.  Call us at 615-802-2665. We’ll help you get the most life out of your HVAC system.