High Efficiency Furnaces

If you’re like most people, you’re concerned with getting the biggest bang for your buck when it comes to heating and cooling your home, and you may also be concerned about helping the environment by leaving a smaller carbon footprint. Energy efficiency is extremely important, which is why it’s become such a hot topic in recent years and why building codes have increasingly become more and more strict in dictating that homes be built to higher efficiency standards. An energy efficient home is more comfortable, less expensive (in the long run), and more valuable than a home that lacks efficiency, and less waste is always a good thing.

In this article, we’re going to focus on just one of many systems that determines the efficiency of a home: your furnace, and gas furnaces in particular. Many homeowners don’t know the efficiency of their furnace, let alone how it operates or what makes one heating system more efficient than another, and I hope to equip you with some basic knowledge so you can check your own system and ensure you’re getting the best value possible.

But first, a little history… for a very long time, homes were heated with low-efficiency, passive heating systems that had an efficiency rating of about 60% to 70% at best. This means that for every hundred dollars homeowners spent to heat their house, only about $60 to $70 was actually used to provide heat while $30 to $40 went out the chimney and was wasted. Not only that, but many homeowners had to perform manual labor to load, light and stoke their furnaces with a fuel source like wood or coal, which was manually delivered or obtained from the land. If that doesn’t sound like your cup of tea, be very thankful you’re alive today and benefiting from modern technology! There are actually plenty of people who still live this way and even prefer it, but the average American would rather not be burdened with so much work. For what it’s worth, though, I would argue that there is something fulfilling about doing things the old fashioned way. Still, I certainly prefer a high-efficiency and very low-maintenance heating system, just like the next guy!

Fast forward to the 1980’s, and some pretty revolutionary innovation began to take place. Lennox – a well known and reputable company – introduced the popular Pulse furnace, which achieved a much higher efficiency than what was even thought possible before. The company wasn’t shy about promoting it either, and the Pulse furnace may be the best marketed furnace of all time. Throughout the 80’s and 90’s, manufacturers learned various ways to design furnaces to use more of the heat they produce, and 80% to 90% became a more common efficiency standard. A furnace during that time period may have had an efficiency rating in the low 80’s but been considered high-efficiency by the standards at the time.

Today, many furnaces are rated at 95% or higher, which is leaps and bounds beyond the older, low-efficiency models that existed for decades. A high-efficiency furnace is a pretty remarkable piece of technology and saves homeowners a great deal of money. So, how do you know if your furnace is a high-efficiency model, and how exactly does it work?

Contrary to low and mid-efficiency furnaces that have one heat exchanger, a high-efficiency furnace has two. This allows the system to use more heat from combustion gases, and it also causes a good deal of condensation to form as the gases condense and form water vapor. For this reason, high-efficiency furnaces are also known as “condensing” furnaces. Because the exhaust gases are not as hot, the vent piping does not have to be metal as it does for older, less efficient systems. Instead, these furnaces use plastic vent pipes (usually PVC), which makes them easily identifiable. In fact, that’s one of the easiest ways (aside from looking at your furnace’s yellow efficiency sticker) to tell whether it’s rated at 90% or higher. If it has plastic white pipes it’s a high-efficiency furnace, and if it has a metal flue it’s not. The pipes for a high-efficiency furnace also don’t need to run through a chimney like metal flues, so you’ll typically see them protruding through a side wall of the home, often not far from the ground.

Like all good things, though, condensing furnaces do pose some potential drawbacks – namely the fact that they produce so much condensation. The water that is produced can wreak havoc on a furnace if it isn’t adequately contained and controlled, and it’s something we come across during inspections more often than you might think. The condensate must be contained so it can’t spill out anywhere inside the furnace, because this can lead to corrosion and eventual damage that destroys the system – especially if heat exchanger damage occurs. The condensate must also be drained away from the furnace, and the drain line has to be clean, unobstructed, and free of kinks so the water can easily move through the line. If the condensate doesn’t drain directly into a floor drain via simple gravity, it often first runs into a pump where it’s pumped upward and over to another drain, like a utility sink, and the pump is a mechanical part that is prone to eventual failure. Problems can arise any time, so periodic monitoring is a must if you have a high-efficiency furnace.

Sufficed to say, high-efficiency furnaces present a handful of potential problems, but they’re still well worth it as long as they are well looked after and maintained. Having $95 or more of every $100 you spend actually being used as intended is far, far better than only $80 or even $85. If you take the time to do some simple math and multiply that extra $10 or $15 for every $100 over many months and years, it will add up to a substantial savings very quickly.

Now, remember how I mentioned that older furnaces with an efficiency rating in the low 80’s were considered highly efficient for their time? That’s important to know because some manufacturers labeled them that way right on the furnace panel. Just the other day, we inspected a home with an oil furnace that had an efficiency rating of 81.4% that said “high efficiency” right on its front. By today’s standards, that furnace is not efficient, so be careful to check your own furnace beyond how it’s advertised – especially if it’s older. Likewise, some of the Lennox Pulse furnaces I mentioned (particularly those from the 1980’s) do have a known history of being susceptible to excess corrosion, so be sure to have yours checked and serviced at least annually by a qualified HVAC technician if you have one.

You may or may not know how efficient your current heating system is, and if you don’t I would strongly encourage you to check. If your furnace is older and not very efficient, you may want to consider upgrading to a more efficient system in the future. If you’re currently in the market for a new system and plan to stay in your home for a while, going the high-efficiency route is a no-brainer. You can also get highly efficient boilers, by the way, so this technology is not limited only to forced air systems. HTP and Buderus are a couple of popular high-efficiency manufacturers in the boiler world, although plenty of other companies also now offer great systems that will save you a lot of money and help improve the value and overall comfort of your home.

Check your furnace, calculate your potential savings, and make a plan to upgrade if you haven’t already. You won’t be sorry, but you’ll need to be diligent about maintaining your furnace often and as best as possible. That’s where a good HVAC company comes into play, so be sure to also establish a good relationship with an experienced and trusted professional to install and service your system.

*To visit our main website, go to http://www.hillinspections.com

Upside-Down Insulation

One of the most common defects we come across – and usually in nicer homes – is insulation that has been installed upside-down. In particular, paper faced fiberglass batts are always the culprit. This is the type of insulation that probably immediately comes to mind when you hear the word “insulation”… long, rectangular batts (usually pink, white or yellow) with a brown paper facing that exists as a vapor barrier. It can lead to a host of problems when improperly installed, and we’ll go over the most common issues and the basic rule for installation so you can check the insulation in your own home and (hopefully) have it corrected if need.

But first of all, let’s begin with a truth that most people either aren’t aware of or don’t want to admit. With the many innovations that have come along in the world of insulation in recent years, fiberglass batts are no longer a very good option for most applications. There are now a number of superior products – all of which can be used in areas where fiberglass batts long reigned supreme – and they should be used. As with most things, it takes quite a while for products to really “catch on”and for contractors to become completely comfortable with the installation, and that’s one of the reasons fiberglass batts are still so popular despite the availability of several far better products.

For many years, contractors and DIY homeowners have been installing batt insulation and have loved its ease of installation and low cost. Closed cell spray foam (arguably the best product available today, depending on the application) isn’t nearly as easy to install and is quite a bit more expensive, so it isn’t the go-to option for most people. Even mineral wool, which also comes in batt form and is easy to install, is a little less familiar and a little pricier. Old habits die hard, and that axiom rings true for fiberglass insulation as it does with so much else. You don’t have to go all-or-nothing with insulation to achieve a good result, though. One fairly popular method nowadays is having one inch of spray foam applied to create a water and air-tight barrier, along with increased rigidity, and then to fill the rest of the cavity with another, less expensive type of insulation.

So, back to upside-down batts and why they’re a problem… Remember how the paper facing of the insulation acts as a vapor barrier? That’s important because a lot hinges on that barrier being installed on the proper side (and it often isn’t). The simple rule for faced batt insulation is that the brown side should always face the conditioned side of the home. Think of the house as a box you’re looking at from the outside, and then envision all of the brown (the vapor barrier) facing inward. If the insulation is in an unfinished basement, a crawlspace or a drive-under garage, the brown should be facing upward and not visible when you’re inside and looking up. If it’s in an unfinished attic, the brown should be facing down and, again, not visible if you are looking at it from within the attic. If it’s in the exterior walls surrounding the main floor(s), the brown should face the interior and be visible if you were to remove the drywall. Pretty easy, right?

You’re likely wondering, if this rule is so simple, why is it so hard for people to understand and follow? Well, one reason is that many people – even contractors – simply don’t know this rule or get confused when they try to remember the direction the insulation should face. The primary reason, though, is that people are so used to installing batts in wall cavities where the brown side should be visible that they just install it that way regardless of the location. It’s also much more pleasant to touch the paper faced side than the itchy, irritating fiberglass, and the brown side has tabs that conveniently fold over to easily staple the batts to studs, joists and other framing members. Even people who know the simple rule we just went over have a tendency to take the easy road and trust it won’t lead to any major issues in the near future, and professionals know that the average homeowner will have no clue that the way they installed their new insulation is improper.

OK, so you’re probably wondering why this rule exists. Why does the vapor barrier need to be facing the conditioned side of the home, and what, exactly, can happen if it’s installed in reverse? Because the vapor barrier blocks water vapor, air that contains vapor and gets into the insulation can condense if there’s a temperature difference (as there always is between finished and unfinished spaces). Once that happens, the condensation won’t have anywhere to go since there’s either sub-flooring above or ceiling material below, so it becomes trapped and often doesn’t quickly evaporate out. Over a long enough period of time and that continually happening, the insulation can compress, lose its R-value and even become a breeding ground for mold and other contaminants. To make matters worse, the paper facing has a black coating, so you likely wouldn’t even notice this happening until it has caused the insulation to sag or fall from a floor structure or drastically compress in an attic. Vented crawlspaces that are naturally prone to high moisture levels are especially susceptible to damaged, falling batt insulation, and we unfortunately see it all too often during inspections. To make matters worse, the batts are usually just friction fitted into place without any wring or other supports whatsoever. The only saving grace to the insulation being able to fall is that it won’t stay pressed against the subfloor where the condensation can lead to eventual rot of the wood floor structure. I often think of falling insulation in vented crawlspaces as alarms… when the batts fall, you know you have a problem and may want to check out your floor structure!

Take some time to walk through your house to check the insulation. If you have fiberglass batts in your basement ceiling, crawlspace floor or attic, make sure that you can’t see the brown side. If you can, gently pry away some of the sides to look around and make sure there isn’t any mold growth or wood/drywall deterioration. You may not have a glaring issue now, but it wouldn’t be a bad idea to budget for a reputable insulation contractor to evaluate what you have and to make recommendations for repairs since it’s only a matter of time before problems do develop. This won’t only prevent possible long-term damage; it will help improve energy efficiency, comfort and value. The bottom line: fiberglass batts aren’t all they’re cracked up to be, and you’d be wise to make sure yours are at least properly installed.

*To visit our main website, go to http://www.hillinspections.com