In a previous post, we talked about zoning: creating separate thermostatically-controlled areas within your home to help even out the hot and cold spots. Although zoning can save you up to 30% in energy costs, it is not without cost itself. Suppose you don’t want the expense of replacing your current system with a new multi-zoned HVAC unit, or re-working your current ductwork layout to accommodate a retrofit. Never fear! There are lots of things you can do to address and possibly alleviate the uneven temperatures in your home. In this post (the first of a 3-part series), we’ll focus on how sealing and insulating ducts may help.

Step 1: Seal the ducts

Ductwork is used to distribute the heated or cooled air throughout your home.  In a typical home, 20-30% of the air in the ductwork is lost due to leaks, holes, and poor insulation.  The result is difficulty keeping the house comfortable no matter how the thermostat is set.  Check the ducts in your attic, crawl space, and basement, and look for holes or gaps, areas where the ductwork has been crushed or kinked, or has become disconnected.  Repair and seal the holes using mastic sealant or metal-backed (foil) tape – NOT the typical grey fabric duct tape! Contrary to its name, “duct tape” is not the best solution for sealing ducts.  Cloth-backed utility tapes are not recommended because they will fall off easily, degrade with extreme heating and cooling, and do not reflect heat.  Look for aluminum-backed tape with the Underwriters Laboratories (UL) logo. Duct mastic is the preferred material for sealing ductwork seams and joints, especially irregular or jagged edges.

Step 2: Seal Registers & Vents

Check all the air register vents in each room, and the return air grill, to ensure there is a tight seal between the duct opening and the grill, that there are no tears in the ductwork from debris falling inside the register, and that the duct has not torn away from the opening.

Step 3: Insulate the ducts

Insulate the ducts, especially in the attic where the temperatures soar in the summer, and in the crawl space and basement where the temperatures are coldest in the winter.  Wrap all ducts with foil-faced fiberglass insulation having an R-6 value or greater and seal the joints with foil-faced duct tape.

Prefer a hands-off approach to your ductwork?  If you live in the Nashville and surrounding area, call on Interstate AC Service at 615-802-2665 to help with ductwork repair, or whatever heating and cooling issues you may have.  We’re here for you!

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!

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.

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.

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.

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.

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!

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.

In the fall and spring of each year, remembering to change the direction of rotation of your ceiling fans may make a bigger difference than you think!  Knowing which direction they should rotate can sometimes be trickier than it seems. Suppose the directions say the blades should turn clockwise, does that mean clockwise when you’re looking down the shaft of the fan from the top?  Or does it mean clockwise when you are below looking up at the fan? They’re not the same! So here is the definitive way to know how to set your fans for any given time of year or situation.

Heat Rises

First, you need to remember one basic principle: heat rises.  Whether it is summer or winter, whether you’re running your air-conditioner or heat, the warmest air will always tend to pool toward the ceiling and the cooler air will always tend to pool towards the floor. This is even true if your air-conditioning vents are set in the ceiling or your heating vents are set in the floor.

Fan Blades Are Angled

If you look at the fan blades, you’ll notice they are not set exactly horizontally in the fixture. They are angled slightly. If you imagine the blades as big spatulas mixing up a cake batter, you can envision that if the blade moved in one direction, the strokes of the spatula would be angled upward.  Moving in the opposite direction, the spatula strokes are angled downward.

Where Do You Want the Air to Go?

In the summertime – or any time you are feeling too warm – you want to feel a breeze of cool air.  The best way to do this is to be sure the fan blade is “scooping” up the cooler air below and wafting it upwards. In other words, the “spatula” should be stroking upwards.  In the wintertime – or any time you are feeling too cool – you want that warm air trapped up by ceiling to come down and surround you.  So you want the fan blades to be pushing the air downward.

How Do You Change It?

You are never really changing the angle of the blades – they stay stationary inside the fan fixture. However, there is usually a small, two-position switch somewhere near the fan motor (towards the center mechanism, not on the blades).  Turn the fan on and observe which way it is “scooping” the air: upwards or downwards.  If it needs to be changed, turn the fan off and wait for it to come to a stop. Then flip this switch in the other direction, and turn the fan back on.  Never try to flip this switch while the blades are still rotating!

Use Fans Year-Round

Most people have no problem using ceiling fans in the summer to create a “wind chill effect” – in other words, to increase evaporation from the skin, which makes us feel cooler.  But many avoid using their fans in cooler months for that same reason.  But if your ceiling fan is spinning the correct direction (as described above) you can save as much as 15% on heating costs… just turn the fan to a lower speed setting to minimize the wind chill effect.  Look at it this way: you’ve already paid to heat the air that is now trapped near the ceiling… why not spread it around to help warm the people in the room? This is even more critical if you heat the room with a form of localized heat – such as a space heater or wood-burning stove.

Saving Energy, Money, and Feeling More Comfortable

By having fans rotating the correct direction at any given time of the year, you can save money on your heating and cooling costs because you’ll be saving energy.  You’ll be able to set your thermostat higher in summer and lower in winter and still feel comfortable.  By moving the air, fans help to “mix” the various layers of cooler and warmer air that naturally stratify due to physics.  This will help your HVAC system run more efficiently and increase your comfort, no matter the season.

Important Tips

If your ceiling fan does not have a way to “winterize” it (e.g., to change rotation direction), consider replacing it with a model that does. Also, don’t forget to clean the fan blades and replace any burned out light bulbs (if your model has lights) while you’re flipping that switch. Ceiling fans should only be used in rooms with ceilings at least 8 feet high.  For optimal performance, the fab blades should be 7-9 feet above the floor and 10-12 inches below the ceiling.  Larger ceiling fans can move more air than smaller fans, and a larger blade will also provide comparable cooling at a lower velocity than a smaller blade.  Some large rooms are best served by installing 2 or more ceiling fans. We recommend fans that have earned the EnergyStar^® label – they move air up to 20% more efficiently than standard models.

Here’s another tip for the changing seasons: Remember to schedule an HVAC maintenance tune-up to ensure there are no surprises later in the dead of winter or the heat of summer.  And, we can’t preach it enough: the most important thing you can do to keep your HVAC system running more efficiently and prolong its life is to change your air filters. Set up reminders every 3 months and never miss a filter change.

If you live in the Nashville or surrounding area, Interstate AC Service can get your HVAC system ready for whatever lies ahead. Call on us at (615) 832-8500.

There will come a time in the life of every HVAC system when it will need to be replaced. See our post on repair or replace to get tips on how to tell whether your unit is a candidate for replacement. Once that decision is made, it is wise to get a couple of quotes. Replacing an HVAC unit is definitely not a do-it-yourself project! It takes an experienced estimator, specially trained installers, and special tools. Plus, in most shops, installers are not repair technicians, as different skills are involved. In this video, we follow along while one homeowner gets an estimate to have the HVAC unit replaced during the remodeling of a 1950’s era house in West Nashville, and a second homeowner in a 1928 home has their second floor unit replaced.

1. The first step is to perform a survey to be able to estimate the work to be done. Tommy Gentry, Service Specialist, has a conversation with the homeowner.
2. When the survey is complete, Tommy writes down all data and gives the homeowner a price. Once the homeowner accepts the price, Tommy makes arrangements for the installation through the scheduler, allowing for all needed parts to be available, and on a day convenient for the homeowner. In this second case, it was 3 days from the date of the estimate until the job was completed.
3. The truck arrived at 8:30am loaded with all the parts and gasses required. The HVAC unit being replaced was on the second floor of the house. Care was taken to lay down cloth mats over all the carpets and floors in the HVAC unit’s path.
4. Next, the refrigerant was removed from the outside unit with an electric pump, and loaded into a recycle can. A pressure meter is used to determine when all the refrigerant has been removed. It is illegal to let refrigerant escape into the atmosphere due to its harmful environmental effects. This refrigerant, called R-22, can be cleaned and used for repairing older units. New HVAC units use a different type of refrigerant, R-410A, which is more environmentally friendly. Since federal law has phased out production of R22, making prices skyrocket, it is worthwhile to capture it so it can be recycled.
5. Next, demolition of the inside unit began. The power was turned off, the power wires to the unit were cut, and the thermostat was disconnected. It was now safe to cut the copper refrigerant pipes. All pieces of the old unit were removed and carried out.
6. The new inside unit was installed and all the connections were made. A special propane torch was used to make the copper refrigerant line connections.
7. The outside unit was completely disconnected and the parts were carried away.
8. The old HVAC base pad was removed. The ground was leveled underneath and a new base pad was installed that was much sturdier than the old one. Having a level pad is essential to the HVAC unit’s operation.
9. The new outside unit was installed on the new base pad, and the power and control wires were connected. As before, a propane torch was used to connect the copper refrigerant lines.
10. Now it was time to test the refrigerant lines for leaks. Nitrogen under pressure was introduced from a container. Nitrogen is an inexpensive inert gas. It is used for testing rather than using actual refrigerant – in this case R-410A refrigerant – because if there is a leak detected, it would all have to be removed, the leak fixed, and fresh expensive R-410A installed. In his case, there were no leaks so the job continued.
11. The electric pump was used to remove the nitrogen and the pink container R-410A refrigerant was installed.
12. The new system was tested in both heating and cooling modes, and worked really well.
13.  The last step was to load all the trash on the truck and haul it to the recycle yard.

Let Interstate AC Service help you make wise investments when it comes to heating and air-conditioning. If you live in the Nashville or surrounding area, give us call at 615-802-2665.