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By Karen, on January 4th, 2012
In heating and air conditioning units, motors generally have two speeds – they’re either full speed or stopped. To get an idea of what this means, it’s similar to driving your car by alternating between flooring the gas pedal and slamming on the brakes. In addition to being an enormous waste of energy, it’s also very hard on the car, or in this case, the HVAC unit.
 Controlling a motor without a VFD is like flooring the gas pedal on your car and using the brakes to regulate speed. In an effort to make motors more efficient and reduce wear and tear, the Variable Speed Drive (VSD) or Variable Frequency Drive (VFD) was introduced to allow motors to run at varying speeds. With these drives, your motors can start up more slowly and build up to max speeds, if needed, or run at lower, more efficient speeds.
 Variable Frequency/Speed Drive The VSD and VFD drives function like a brain for the motor. They tell the motors exactly how fast and how long to run to maintain desired temperatures, airflow, etc. At lower speeds, your motor is still able to provide you with ideal comfort but at much less cost. To put a number on it, motors running at full speed use nearly 8 times more energy than a motor running at half speed.
In addition to saving energy and reducing wear and tear on your equipment, the drives can also alert you about malfunctions or needed maintenance, minimizing equipment downtime. In some cases repairs can be done even before anyone notices a problem.
VFD and VSD drives can be used on equipment such as fans, hot water pumps, compressors, etc. They can be paired with high efficiency motors for a double whammy of efficiency. Plus VFD/VSDs qualify for huge rebates from utility companies, making it even more cost-effective to invest now.
To find out how VFD/VSDs can work for you, see energy savings calculations, etc., please call us or visit our website at http://www.advanceair.net/vfd-vsd.htm.
By Karen, on December 8th, 2011
Sometimes it’s hard to see past the dollar signs, but would you hire the cheapest day care provider, site unseen, just because they were the cheapest? How about the cheapest brain surgeon? So what if he graduated last in his class and doesn’t have the most up-to-date equipment? It’s only your brain!
Quality plays a major role in pricing, and for good reason.
- For Installations, research and development costs and higher quality raw materials increase the price of HVAC equipment. Because of those higher costs, the equipment will be more energy efficient, last longer and be more reliable than cheaper equipment.
- Labor costs vary by skill level. Hiring, retaining and continually training employees is expensive. But the alternative is cheaper, less skilled, less educated labor installing your expensive HVAC equipment. The highest efficiency equipment, if installed improperly, will be less efficient than standard efficiency equipment.
- Good, honest business practices have a lower profit margin than shady ones. Cutting corners and playing games with change-orders after the fact gets upfront prices down, but costs more in the long run. And you don’t get what you thought you were paying for.
In order to make sure that you get the right unit, installed correctly, by a company that stands behind its work and provides quality service, you have to consider more than just price. First, establish a quality threshold for both the materials and the contractor. If you stay within the major HVAC unit manufacturers, you should be OK quality-wise. Make a note of the efficiency of the units on proposals to make sure you’re comparing apples to apples. Check contractors for proper licenses and insurance, and request references. Only after you’ve established that the equipment is comparable and the contractors reputable, can you safely let price be your guide.
Advance Air is not the cheapest contractor in town – and we’re not ashamed to admit it. We have value that the cheapest contractor doesn’t have.
We hire and continually train high caliber employees. We price your project honestly upfront and follow through on our commitments. We stand behind our installations and make sure our customers are fully satisfied. Anything less wouldn’t be acceptable to us or our customers. Even with this high level of service, we are priced lower than our similarly skilled competition because of the way we manage our business and our comparatively low overhead costs.
By Karen, on October 20th, 2011
For small offices, historic buildings, or other applications where ductwork is too costly, impractical or even impossible, there is a quality alternative. Ductless systems provide multi-room air conditioning that’s quiet, attractive and effective.
 Modular systems available. Add up to four indoor units to heat and/or cool multiple rooms. The traditional alternatives to central air conditioning – window or through-the-wall units – will get the job done, but they can be loud, unattractive and inefficient. See a detailed comparison chart on our website.
Through-the-wall units, or PTAC (Portable Terminal Air Conditioning) Units, are installed by cutting into an exterior wall and placing the unit inside a special sleeve to hold it in place.
Window units, as the name implies, are placed into a partially-opened window.
Window and through-the-wall units have potential security issues – a unit could be removed for access into a building through the unit opening.
Both are also noisier because they have the condenser motor and fan inside your room. In ductless split units, the noisy condenser is outside.
Ductless splits have some of the highest rated efficiencies available. And because the air doesn’t have to travel through ducts – usually located in 100 degree attic spaces – there are none of the usual energy losses associated with ductwork (a typical system loses 30-50% efficiency in the duct system). All of the cooling/heating goes right where you want it. Ductless systems can also provide heat as well as air conditioning, if needed.
For more information, or to find out if ductless split air conditioning systems are right for your business, call Advance Air at 508-763-3738 or send an email to info@advanceair.net.
By Karen, on October 14th, 2011
One day, after a particularly frustrating bidding experience, we were blowing off steam in the office and came up with a little jingle that had all of us giggling. I had forgotten about this little ditty until a new business colleague called it to my attention after browsing our website and stumbling across the link to the song.
I think everyone, at one time or another, has made an unfortunate contracting decision based solely on price, only to find out that you truly do “get what you pay for.” It’s just a little bit of fun that I thought I’d share. I hope you enjoy it as much as we enjoyed creating it.
You Give Contractors a Bad Name
(Sung to the tune of Bon Jovi’s “You Give Love a Bad Name” )
A substandard product is what you sell
You promise me service, then put me through h—
Low bid price got a hold of me
When price is a prison, I can’t break free
Ooohh, your low bid won
Oh no, it’s not gonna run
Advance Air can save you
Get the damage undone
Shot in the dark
And you’re to blame
You give contractors a bad name
We play by the rules, but you play your game
You give contractors a bad name
You give contractors a bad name
Plaster a smile on your lips
Dangle your bid from your fingertips
Your price is a dream, you act so sly
Your very first change order is your first kick in the eye
Oooh, your low bid won
Oh no, it’s not gonna run
Advance Air can save you
Get the damage undone
By Karen, on August 26th, 2011
I was recently interviewed on a local AM Radio Show, hosted by Tech Angel Pam Viveiros from ThinkTech Computers to discuss technology in the field of HVAC. I listened to the recording of the broadcast – I had to, because I was so nervous I didn’t remember what I’d said – and couldn’t help but think that there’s just soooo much I didn’t cover, specifically in the area of Building Automation.
In the radio show, I compared Building Automation to the awesome
 Stand aside Jetsons! Building Automation has come a long way since the 60's. automation seen on The Jetsons, the 1960’s animated sitcom with robots and automated everything. That level of automation is now a reality for many commercial buildings – though on a more practical scale. Building Automation Systems (BAS) can be used to program and controls everything from HVAC, lighting, security, process equipment and more. And it all comes in a user-friendly interface that can be accessed from your on-site computer or by logging in remotely with a secure internet connection.
Now why would you want a “Jetsons” automation system in your building? Rather than list the capabilities of a Building Automation System, I thought I’d give a little day in the life peek into some of the things it can do for you. Wish I could animate it like the Jetsons opening sequence. Maybe next time…
6:00 a.m. It’s a typical early fall morning. Birds are chirping, sun is shining and the BAS system has the rooftop economizer fully open, letting the 62°F air cool off and freshen up the building before the first employee arrives. No need to fire up the cooling condensers yet. Save your energy for later. It is New England after all, and you never know what temperature you’re going to get.
6:30 a.m. Mary arrives, swipes her security card at the front entrance, BAS system recognizes her as an authorized user and as it allows her through the turnstile, automatically turns on the lights in her office on the second floor.
7:00 a.m. Mary is still chatting with Anne at the water cooler. BAS hasn’t sensed any movement in Mary’s office in the last half hour, so the lights switch off to conserve energy.
11:30 a.m. The sun is still shining, but it’s a wacko New England Fall day where the temperature climbs to 80°F in just a few hours – not to mention the crazy humidity that came out of nowhere. But no need to worry, the BAS system has already detected the rise in humidity and backed down that economizer so you’re not cooling the hot wet air from outside, but recycling the already cooler drier inside air.
2:00 p.m. That lunch meeting in 3rd fl conference room has gone long, there’s lots of hot air to trigger those CO2 sensors to increase the fresh air to the room and cool down the hot tempers in those tight collars.
3:00 p.m. Meeting has finally ended (thank goodness) and everyone’s back in their offices. As soon as the coffee cups are cleared away, BAS turns off the lights, cooling and fresh air.
5:30 p.m. Normally the building would be in night setback starting at 5:00, but BAS can sense the Anne is still hard at work (catching up after that long meeting and the earlier water cooler chat with Mary) and keeps things cool for her. It’s cool again outside, so BAS switches back to free cooling from outside air.
6:30 p.m. It’s Fall in New England, so it’s already getting dark. Anne’s not worried though because the BAS System has already turned the parking lot lights on. Anne leaves for the night and BAS closes up the systems behind her and the building can go into sleep mode for the night, saving bunches of energy in setback mode.
The brilliance of BAS is that without thinking about it, you only use the energy you need – no more, no less. And you get the benefit of full comfort, temperature, humidity and fresh air at the same time. For less money, you receive much better comfort than you had before, because you’re measuring more inputs and making better control decisions with the information. So though the BAS system can’t bring you breakfast like the Jetsons, it can make you completely comfortable while you’re eating it and save you hundreds, even thousands on your energy bill. Stand aside Jetsons!
By Karen, on July 28th, 2011
Energy accounts for about 30% of operating costs for a building, according to the Building Owners and Managers Association (BOMA). The total energy consumption for the month accounts for the major part of the energy expenses, but it is only part of the picture.
Depending upon how you use energy, a Demand Charge could be a significant part of your overall energy costs. In the case study featured in my last blog, the Demand Charge represented 10% of the total energy bill. Demand Charges are controllable and should be part of the overall energy strategy.
 Demand Charges are controllable and should be part of the overall energy strategy. Demand Charges are dictated by your peak demand. To get a better idea of what peak demand is, think of it this way: if you turned on one 40 watt light bulb for an hour, shut it off, then turned on another 40 watt light bulb for an hour, you would have consumed 80 watt-hours of electricity, but since you only had one bulb on at a time, your peak demand would be only 40 watts. If you turn both 40 watt bulbs at the same time and leave them both on for an hour, your energy consumption after an hour would still be 80 watt-hours, but your peak demand would increase to 80 watts. Your usage bill would be the same, but your demand charge would be double!
Though it is certainly not practical to keep half of your building in the dark, there are many clever solutions with HVAC scheduling that can keep you comfortable while reducing your peak demand. When your Energy Services/HVAC Contractor has reduced your overall energy consumption, make sure they take the next step to reduce your Demand Charges as part of your energy strategy.
Here are some clever ways you can reduce your peak demand without impacting your comfort or productivity:
- Stagger Occupied Start Times of HVAC – If you can prevent multiple units from starting up simultaneously, you can reduce peak demand. For example, if a building has four rooftop units serving four different spaces, you can set each area to come on in sequence, rather than all at once. You may need to program start times a little earlier in the morning to get all rooms to temperature before the start of the day, but you won’t have a spike in energy demand all at once. Start times should be at least 20 – 30 minutes apart to make sure that you don’t overlap.
- Using sequencing techniques for HVAC units - When outside temperatures are moderate, you don’t need to run multiple stages of heat or cooling simultaneously to achieve comfort. HVAC systems are typically sized to meet your needs on the hottest/coldest days. Since most days are not so extreme, you don’t need to run both stages at once to effectively condition your space.
- Look at Heating and Cooling Set Points – We all know comfort can be a very subjective thing. One person will be wearing a sweater next to someone in a tank top. If you can get away with running a little warmer in the summer 72 instead of 70, or a little colder in the winter 68 instead of 70, you will use less energy overall, and reduce peak demand at the same time.
- Control Outside Air Intake – We all have heard about sick-building syndrome from buildings not having enough fresh air. But the opposite problem is actually more common. Most buildings exchange too much air. All that nicely conditioned air is literally going right out the window. By better controlling your outdoor air intake, you can still have healthy amounts of fresh air, and not cool or heat more air than you need to. This can be achieved by simply manually adjusting outdoor air dampers, smarter control of economizers, or by installing Demand Control Ventilation. Demand Control Ventilation actually measures the amount of carbon dioxide in a space and increases fresh air only as needed. It completely and automatically eliminates over-ventilation.
These are just a selection of the strategies that you can use to reduce your demand charge. Most can be easily accomplished through your existing Building Management System or by adding inexpensive programmable thermostats, sensors and controls.
Based on your specific operation, there may be even more ways that you can reduce your bill without creating noticeable changes in your work environment. If you’re interested in ways you can reduce your overall energy bill – or demand charges specifically – send us your energy bills and we’ll introduce you to our Energy WatchDog Killer Watts.
By Karen, on May 16th, 2011
As if it isn’t confusing enough that electric utilities charge delivery charges and generation charges, they also have a funky little thing on business energy bills called a Demand Charge. What ARE all of these charges? And how do you make them go away?
Every utility has their own billing format and pricing structure. The most popular utility in our service area is NSTAR, so most of the examples in this blog will refer to the typical NSTAR bill for a medium sized business. If you’d like an analysis of your specific bill, you can email me a copy and I’d be happy to break it down for you (please limit this to business bills from Southeast MA only).
 Confused by your energy bill? Email me. NSTAR is an energy re-seller. They deliver electricity but do not necessarily generate it. Because of this, there are separate charges for delivery and generation. The fee for delivering your energy covers the cost of building and maintaining wires. The generation fee pays for the energy NSTAR buys from the generating plant. These, among a few other small miscellaneous charges and taxes make up the “usage” part of your bill.
In addition to usage charges, there is another significant charge called a Demand Charge. NSTAR electric meters automatically record the peak level of energy demand during every month. The idea behind a Demand Charge is that the utility must have enough energy available to satisfy your peak demand at any given time. You won’t always be using your peak, but they must have it available, just in case. The Demand Charge is a way to offset the cost of the providing this just-in-case energy.
Here’s how a Demand Charge can affect your bill. If you consumed 15,000 kWh of electricity during the month, your usage charges might look like this:
Delivery Charges (per kWh) 8.6 cents x 15,000 kWh = $1,290
Generation Charges (per KWh) 8.0 cents x 15,000 kWh = $1,200
Total Usage Charges = $2,490
The demand charge captures the moment you had the most items turned on at once. Let’s assume your peak demand was registered at 60 kW this month. Peak demand only a snapshot of energy consumed it is measured in kilowatts (kW) versus energy consumed over time which is measured in kilowatt-hours (kWh). Your Demand Charge would be as follows:
Peak Demand 60 kW
1st 10 kW is free -10 kW
Adjusted Peak 50 kW
Demand Charge (per kW) $4.86 x 50 kW = $243
Although energy consumption is clearly the major part of the energy expense, the Demand Charge (equal to 10% of the total energy bill in this case) is controllable and should be part of the overall energy strategy.
Energy accounts for about 30% of operating costs for a building, according to the Building Owners and Managers Association (BOMA). Though no one can make their energy bills go away completely – short of resorting to using candlelight and the abacus – there are strategies to get the most out of your energy dollar. Check out our website for more info: www.advanceair.net/energy.
By Karen, on April 28th, 2011
Having just launched our Energy WatchDog Program, I’ve had the…well I don’t want to say pleasure but let’s call it opportunity…to become familiar with energy metrics – kilowatts and kilowatt-hours and the like. Personally I would like to have words with the person who invented the term “kilowatt-hour” as it does not necessarily refer to an hour, but the consumption of energy over a vague period of time which could literally be an hour, 24-hours, a month, or any amount of time which floats your boat.
For example, a 60-watt bulb will use 60 watt-hours (or 0.06 kilowatt-hours) of energy in an hour, but you could also say that it will consume 1,440 watt-hours (or 14.4 kilowatt-hours) in 24 hours. Whether or not energy consumed was during an hour, a day, or a year, you will still see a watt-hour or kilowatt-hour (kWh) designation. And that’s just the start of the confusion.
One helpful blog article that I found recently does a good job explaining the concept of watt versus watt-hour and also has some clever-cute “screw in a light bulb” jokes to boot. The blog, “What is a Watt, Anyway? Understanding Energy and Power Metrics” posted by Tristan Roberts on BuildingGreen.com discusses the following:
- Watts are basically the miles-per-hour measurement of the electrical world–they tell you how fast the electrons are speeding down the highway (i.e. a 60-watt bulb is going 60 watts per hour – that’s fast!). A watt is a measure of speed of electrons, otherwise known as “power.”
- While a watt is a measure of power, a watt-hour is a measure of energy. When you get your utility bill, the electricity you’ve used is measured in kilowatt-hours (kWh) or kilowatts consumed over a period of time. Energy is defined as the capacity to do work, such as creating heat, light, or motion. Kilowatt-hours is the measurement of energy consumed over a period of time.
- Commercial and industrial facilities typically pay “demand charges,” which are calculated based on their peak power draw (usually measured in megawatts, or MW), which compensates the electric utility for ensuring that it has enough power available to meet that demand.
Though this article touches on Demand Charges, I will be exploring them further in future blog articles. An important thing to know about demand charges is that they can be fairly easily reduced using programming and sequencing strategies. More on demand charges to come…
By Karen, on April 1st, 2011
As controls systems age, they can start misbehaving. Because controls systems rely on computer software as well as electronic hardware, they are subject to glitches and performance problems for a whole host of reasons. Sometimes a simple upgrade can resolve issues, other times these glitches are symptoms of bigger problems and an overhaul is your best bet.
 Avoid the Frustration - Keep Controls Current!
When you start seeing the symptoms below, it is a good time to look at replacement, or at least a signficant upgrade:
- Computer system upgrades conflicting with existing HVAC controls software. Some older HVAC software will not run correctly on new computers for a myriad of reasons – incompatible operating system or Java version, missing drivers, incompatible internet browser, etc. These conflicts get worse as the age gap between the HVAC software and the computer grows. And it’s not just one computer you need to consider. Any computer that wishes to view or access the controls system whether on- or off-site, management, maintenance dept. or service contractor may begin to have issues as the age gap grows. Like any computer software, upgrades for both software and hardware are necessary to ensure continued compatibility.
- Obsolete repair parts. As manufacturers move on to the new more powerful controls systems, the older systems get left behind and are not supported. It becomes increasingly difficult to get replacement parts the older a system gets.
- Obsolete communications or connectivity technology. Many older controls systems do not have a user-interface and require special devices to communicate with a laptop. Older systems often use serial cables or PCM-CIA Cards, technologies which are no longer available in new laptops. Often external devices or adapters don’t work, leaving field techs blind when they try to troubleshoot or program an older system.
- Difficulty integrating new controls onto old controls systems. Though advances have been made to better integrate newer systems with each other (even if they are different manufacturers), older systems often have proprietary systems or older technology that doesn’t communicate with newer devices, even from the same manufacturer. If you are adding new HVAC equipment to your old controls system, you may have problems making everybody play nice together. It’s like trying to play a new CD in an 8-track player.
- Limitations on control system functions like trending or load-shedding. Newer systems include improvements and refinements over the old. You may find your old dog system can’t learn new tricks. This might cost you much-needed efficiencies.
- Un-maintained controls or controls operated by un-trained staff. Though not really an age issue, this is probably one of the single biggest issues in controls today. Controls are incredibly powerful in the hands of those who know how to use them, but can actually work against those who aren’t well trained. Newer systems tend to be more user-friendly. Think of old DOS-based systems vs. Windows®.
Generally we recommend keeping an existing controls system in place as long as it is effectively performing. A well-maintained controls system can last anywhere from 10-20 years, depending on the type of system and its capacity. But the key is to weigh the cost of an inefficient or difficult to service system against the cost of replacing it altogether. Controls are extremely powerful tools that will quickly pay for themselves and provide years of energy savings. But when controls misbehave they can cost you serious bucks. But when you start seeing serious issues cropping up, it’s time to bite the bullet and plan for your new controls system. Waiting to take action can be costly.
By Karen, on March 22nd, 2011
Firstly, when I say “controls system” I mean a Building Automation System (BAS) or Energy Management System (EMS) featuring a system of Direct Digital Controls (DDC) that can be controlled and monitored centrally by computer. For more info on DDC controls, check out this website: http://www.advanceair.net/ddc.htm
A well-maintained controls system can last anywhere from 10-20 years, depending on the type of system and its capacity. Controls are extremely powerful tools that will quickly pay for themselves and provide years of energy savings, but they must be selected carefully, used and maintained properly to get that payback.
Invest in Non-Proprietary Software
Like everything else, in order to get the most out of your controls system, you must invest wisely upfront. Ideally you want a system that is not too highly proprietary – the two most popular platforms are  BacNet® or LonWorks®. Each platform has its positives and negatives in comparison to each other, but both platforms have very good following and seem to be here to stay. Longevity is vital to getting support, replacement parts and easily upgrading or expanding your system in the future. Advances in controls technology even allow these platforms to integrate with each other to some extent.
Properly Train Operating Staff
The next step is to train on-site staff to operate these systems properly. In order to know if you controls system is effectively performing, you need to really understand its purpose and function. Most controls system installers will offer a brief one-time “training session.” This is usually not enough. There are too many bells and whistles to truly understand all of them in one sitting. When your service provider is working on the system, work with them as they resolve issues or update settings, ask questions, every service call can be a learning experience for staff. Any good service provider would welcome the opportunity to share knowledge of the system and provide a little impromptu training session.
Monitor System Regularly and Semi-Annually Review
Controls systems are not “set-it-and-forget-it” investments. At a minimum, they should be monitored daily for alarms and irregularities and thoroughly checked annually or semi-annually to make sure the system itself, as well as all of its settings are maximizing energy savings and control. If on-site staff is unable to provide proper continual monitoring or the semi-annual inspection, this is a service offered by many controls contractors. If systems are set up to be monitored remotely, the cost for daily monitoring is typically minimal and the benefits are enormous. Annual maintenance should be provided on-site, generally during seasonal preventive maintenance visits once or twice per year. This is also a good time to see if expansion or upgrades are necessary.
If you really want to be thorough confirming that your system is functioning correctly, you can also use devices independent of the controls system, such as data loggers, to confirm that the sensors and controls settings are calibrated correctly. This service is often provided by contractors under an Energy Services Contract.
If you’ve selected wisely, had a well-trained staff and/or controls contractor monitoring and maintaining your controls and haven’t done major changes or expansions to your HVAC equipment, you can easily get 10 years out of your initial controls investment. At the ten-year mark, it is time to start looking at options. Can you upgrade the existing system to extend its life? Or do you need to plan for a total system overhaul in the next few years because of system problems or limitations?
Though we all want our controls systems to last forever, next week’s blog will discuss how you will know that it’s time to say goodbye to your old controls system…stay tuned.
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