Category: Heating

A Comprehensive Guide to Variable Frequency Drives

Variable frequency drives (VFD) are used in appliances and compressors of all sizes. They can help make electrical motors more efficient. They work by managing the frequency and the voltage so that they use energy in the most efficient manner possible. They are being used more and more as the development of the technologies has made the drives smaller and improved their performance. Here are some things to know about variable frequency drives.

AC Motor
Usually the motor for a variable frequency drive is a three phase induction. This is because such motors are generally the most economical. Less commonly used are wound rotors, permanent magnets, and synchronous motors.

Controller
A VFD has a controller that runs because of three sub-systems. Those sub-systems are the converter, the DC capacitor, and the inverter assembly. The converter stage is where the AC voltage is converted to DC voltage. The DC capacitor assembly and the inverter assembly work in tandem to initiate the three phase voltage. In 1983, the insulated gate bipolar transistor made it so that a VFD cost less and improved its amperage ratings.

Operating
VFDs have an extensive operator interface. It can start and stop the motor, as well as adjust the speed. There are types that allow for reversing the motor and even switching from manual control to automatic. VFDs are operated by either a computer network, digital controls, or the operator interface controls on the unit.

Drive Operations
A VFD will have three options for driver operations. Single quadrant operations are most common, and involve using constant or variable torque. Two-quadrant loads are needed when the torque alters its polarity but the speed is constant. For the highest performance, a four-quadrant load can handle speeds and torques that change direction and force.

Types of Variable Frequency Drives

Controlled Source Inverter
A controlled source inverter (CSI) works by using a SCR converter to convert all the incoming power to DC. CSI have a large internal inductor so that they can work efficiently and properly to handle the incoming power load. The advantages of this type of VFR are that the circuitry is relatively simple, they are very reliable, and they are capable of regeneration. Some of the drawbacks are that it relies on that large conductor, which is expensive, and that it is not compatible with multi-motor applications.

Voltage Source Inverter
Voltage Source Inverters (VSI) are similar to CSI in that the prime function is the covert power to DC by using a SCR converter section. However, VSI drives cannot regulate current, which the CSI drive can do. The VSI can create an adjustable frequency output for motors.

Pulse Width Modulation
The pulse width modulation (PWM) design is the most common drive controller. It can work with the largest variety of motors, and is very reliable. It is the most sold by manufacturers as well, so there are many brands from which to choose. As opposed the the VSI and CSI drives, PWM converts AC voltage to DC voltage. It does this by using an inverter section that also has gate bipolar transistor that are insulated. This creates a near-sine wave output. These drives are a low cost upfront, are compatible with multiple motors, and can operate through a power loss. The only issues are that it cannot regenerate, and can break down because of the switching transistors.

Benefits of Variable Frequency Drives
VFDs come with a host of benefits. For one, they are very energy efficient, in particular with regards to centrifugal load service. Estimates show that well over 60% of all used electrical energy is consumed by power motors. VFDs and other efficient technologies help to reduce that energy footprint.

Performance Control
VFDs allow you to regulate the amount of power a motor delivers. With fixed speed drive, a motor might be delivering more power than is needed. To have better process control, VFDs will regulate that power and only use as much energy as is required.

Now you know about the different types and benefits of using VFDs. Make sure to choose the right one for the job you have to do.

If you want your HVAC system to run more efficiently, the experts at Corporate Mechanical can help. Reach out online or call 763-533-3070.

Xergy Currently Developing Greener HVAC Systems

Bamdad Bahar is the founder of Xergy. Xergy is a Seaford startup that is working to find a way to make greener HVAC systems for homes and businesses. Their goal is to find a way to convert the membrane technology used in fuel cells for climate control purposes. As a result, modern HVAC systems will be more environmentally friendly. Says Bahar of the project, “There are literally hundreds of applications for this membrane technology in everything from electronics to industrial to medical. But right now refrigeration and air conditioning is our main focus.” But what does this technology entail? How is it different from traditional HVAC technology? And how is Xergy currently developing greener HVAC systems to use on a larger, nationwide scale? Continue reading “Xergy Currently Developing Greener HVAC Systems”

Higher Energy Bills Expected With Longer Winter ’16-’17 Season

Americans living from the east coast to the central plains should prepare for a long winter this year. Information released by ACCUWeather and the US Energy Information Administration (EIA) indicate we will have the coldest winter in years. By contrast, the southern portion of the country can expect a warmer and drier winter for 2016-2017. In addition, the National Oceanic and Atmospheric Administration (NOAA) expects temperatures to be much colder than last winter. With the temperatures expected to be the lowest since 2010, HVAC contractors are making sure people’s heating systems are ready. Whether you use gas, electricity, or oil, higher energy bills expected with longer winter weather are still hard on your checkbook. But just exactly how much can you expect to pay?

Higher Energy Bills Expected with Longer Winter

Temperature Differences

The NOAA expects temperatures that are 17% lower than last year in the midwest and northeast regions. In addition, the South can expect temperatures to be up to 18% colder. The West, however, will likely see temperatures 2% warmer on average than last winter. Says ACCUWeather meteorologist Evan Duffey, “This warmth will come to an end in January, which could be a big month for HVAC contractors as the jet stream changes and cold air spills into the eastern two-thirds of the nation. This even includes Florida, where we are concerned for a freeze this year, which is a very rare event for the Florida Peninsula.”

Higher Energy Costs

With the longer, colder winter expected this year, households and business spaces heated by natural gas are expected to reach $10.37 per thousand cubic feet (Mcf). That’s 11% higher than last winter, and the highest gas prices since the 2010-2011 winter season. In addition, homeowners using heating oil to heat their homes can expect to spend an average of 38% more this winter than last year. Electric heating will also increase by an average of 5% this winter.

Be Prepared

Don’t let the winter chill sneak up on you this year. Prepare your home and business for the colder weather now. Corporate Mechanical can help winterize your HVAC system. Call us today and ask about an inspection and winter HVAC services. With higher energy bills expected with longer winter weather this year, you’ll be doing yourself a big favor. Call today!

More Ways to Prepare a Building for Winter Weather

People are usually well-versed in ways to winterize their homes, but can sometime neglect to apply the same treatment to their commercial buildings. Understanding the precautions necessary to winterize your commercial property is important to maintaining the operations of your business.

Maintenance for the Building

  • Make sure that gutters have been cleared of any objects, including leafs or other organic material. This ensures proper draining during the cold months.
  • Make sure that nothing is blocking your drains. If moisture is not draining properly in the winter, it could cause significant damage. Inspect and roof flashing penetrations or building envelopes as well, and seal them to prevent water from flowing into the building.
  • Inspect gutters to make sure they are properly attached to the building
  • Make sure any accumulated debris is removed from basement and foundation drains, especially the storm drains in the parking lot.
  • Trim any nearby trees or large shrubs to reduce the amount of leaves or branches that could enter the drains
  • Service your heating equipment early. This will ensure that nothing breaks down when it is being used constantly during the winter.
  • Test all carbon monoxide detectors
  • Discourage the use of space heaters, but in cases where they are permitted, make sure they have a UL label

Removing Ice and Snow

A representative for a Denver roofing company offers the following pieces of advice:

  • Make sure you already have the proper tools before winter. This includes shovels, salt and other material to melt the ice, and anything else necessary to facilitate the removal of snow in your area.
  • Review any contracts you have with the maintenance crew if you have hired one. This will reduce the amount of unanticipated bills later in the winter, and ensure you receive the service you desire.
  • Make sure your exterior lighting works. This makes it much easier to remove ice and snow during the evening when the building is closed for business.
  • Start any parking lot repair before winter begins, especially pot holes and curb damage.

Preventing Frozen Pipes

A spokesperson for Asbestos Abatement in Denver offers the following:

  • Make sure any irrigation system is turned off. This will keep water inside the pipes from freezing.
  • Make sure any wall or attic pipes are sealed to prevent airflow near the opening.
  • Consider a temperature alarm in any high risk areas, and add extra insulation near pipes in your attic or basement
  • If possible, let a sink drip if it happens to be in an extremely cold area (only if the water cannot be drained or turned off).
  • Make sure all your windows and doors have the proper sealant, especially if they are in an unheated area of your property.

7 Ways to Winterize a Building

An unpleasant fact of life is that a lot of the energy in your structure or commercial structure spent on heating is wasted due to failing insulation and lack thereof. If you address a lot of the issues you will have a chance to make that a thing of the past, so consider what you can do to make it happen. With the proper insulation, your structure and its HVAC system will be much easier to work with and they won’t waste as much energy trying to keep your building warm. The biggest consumers of energy happen to be large appliances such as freezers, water heaters, dishwashers and washing machines, but HVAC systems can also eat up a lot of energy when they are working with poor insulation. You can work on this before the winter season, allowing you to install all of these and to deal with house cleaning when the job is done. Be careful when working as you may need to perform upholstery cleaning and carpet cleaning if you work with foam. The following examples will explain how you can winterize your building properly to avoid any issues up ahead:
Continue reading “7 Ways to Winterize a Building”

Benefits of Regularly Maintaining Your Furnace

With the summer warmth, many people forget that the fall and winter are just around the corner and that soon temperatures will start coming down. Those who are conscious of the coming winter do their best to get ready by inspecting their roofs, cleaning gutters and disconnecting their hoses but forget a very important equipment in the home i.e. to check whether their furnace is working properly. Following are benefits of having your furnace maintained regularly;

It limits surprises. Ensuring a regular maintenance to your furnace has a host of benefits. With such maintenance, you have peace of mind knowing that you are not likely to experience furnace emergencies when the cold is really biting. Imagine the furnace breaking down on a very cold night just because you didn’t have it inspected earlier? Regular maintenance reveals in advance small problems which could turn into big problems if left unchecked. When you get your furnace checked before winter sets in is very wise as it gives you time to order replacement parts if they are needed, you are also able to check its efficiency to ensure it heats your home effectively as well as order a replacement unit if you find your old one in a deplorable working condition. You don’t want to rush to put on the furnace when the chilly weather sets in only to find out that it is not heating effectively and worse it doesn’t heat at all.

Increase your unit’s efficiency and lifespan. Fall furnace maintenance also helps review your unit’s efficiency. If properly maintained, a furnace can last as long as 20 years or more. Having a professional HVAC technician clean, lubricate moving parts, check connections and check its control’s among other maintenance procedures will ensure your unit operates at maximum efficiency. With such maintenance you will greatly save on your energy bills.

It limits unnecessary repairs. Ensuring a regular maintenance to your furnace will limit the need for repairs over the lifespan of your unit. This translates to less operation costs for the unit. In addition, you are able to last all winter long without having a serious furnace repair or breakdown that leaves you spending a number of nights on the cold.

Be wise this fall, call for a certified HVAC repair technician to come and check your unit. Also, if you can, enroll in a regular maintenance program which ensures the repair company will always come to check your unit even when you forget about it.

How we can fix air conditioning less cooling

Pityful a rethoric question ran over her cheek, then she continued her way. On her way she met a copy.

The copy warned the Little Blind Text, that where it came from it would have been rewritten a thousand times and everything that was left from its origin would be the word “and” and the Little Blind Text should turn around and return to its own, safe country.

O my friend — but it is too much for my strength — I sink under the weight of the splendour of these visions!

A wonderful serenity has taken possession of my entire soul, like these sweet mornings of spring which I enjoy with my whole heart.

I am alone, and feel the charm of existence in this spot, which was created for the bliss of souls like mine.

The Big Oxmox advised her not to do so, because there were thousands of bad Commas, wild Question Marks and devious Semikoli, but the Little Blind Text didn’t listen.

She packed her seven versalia, put her initial into the belt and made herself on the way.

When she reached the first hills of the Italic Mountains, she had a last view back on the skyline of her hometown Bookmarksgrove, the headline of Alphabet Village and the subline of her own road, the Line Lane.

Pityful a rethoric question ran over her cheek, then she continued her way. On her way she met a copy.

The Big Oxmox advised her not to do so, because there were thousands of bad Commas, wild Question Marks and devious Semikoli, but the Little Blind Text didn’t listen.

She packed her seven versalia, put her initial into the belt and made herself on the way.

When she reached the first hills of the Italic Mountains, she had a last view back on the skyline of her hometown Bookmarksgrove, the headline of Alphabet Village and the subline of her own road, the Line Lane.

Pityful a rethoric question ran over her cheek, then she continued her way. On her way she met a copy.

Many desktop publishing packages

No one rejects, dislikes, or avoids pleasure itself, because it is pleasure, but because those who do not know how to pursue pleasure rationally encounter consequences that are extremely painful.

Nor again is there anyone who loves or pursues or desires to obtain pain of itself, because it is pain, but because occasionally circumstances occur in which toil and pain can procure him some great pleasure.

To take a trivial example, which of us ever undertakes laborious physical exercise, except to obtain some advantage from it?

But who has any right to find fault with a man who chooses to enjoy a pleasure that has no annoying consequences, or one who avoids a pain that produces no resultant pleasure?

Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante.

On the other hand, we denounce with righteous indignation and dislike men who are so beguiled and demoralized by the charms of pleasure of the moment, so blinded by desire, that they cannot foresee the pain and trouble that are bound to ensue; and equal blame belongs to those who fail in their duty through weakness of will, which is the same as saying through shrinking from toil and pain.

A paradisematic country

The copy warned the Little Blind Text, that where it came from it would have been rewritten a thousand times and everything that was left from its origin would be the word “and” and the Little Blind Text should turn around and return to its own, safe country.

But nothing the copy said could convince her and so it didn’t take long until a few insidious Copy Writers ambushed her, made her drunk with Longe and Parole and dragged her into their agency, where they abused her for their projects again and again. And if she hasn’t been rewritten, then they are still using her.

Far far away, behind the word mountains, far from the countries Vokalia and Consonantia, there live the blind texts. Separated they live in Bookmarksgrove right at the coast of the Semantics, a large language ocean. A small river named Duden flows by their place and supplies it with the necessary regelialia.

It is a paradisematic country, in which roasted parts of sentences fly into your mouth. Even the all-powerful Pointing has no control about the blind texts it is an almost unorthographic life One day however a small line of blind text by the name of Lorem Ipsum decided to leave for the far World of Grammar.

The copy warned the Little Blind Text, that where it came from it would have been rewritten a thousand times and everything that was left from its origin would be the word “and” and the Little Blind Text should turn around and return to its own, safe country.

But nothing the copy said could convince her and so it didn’t take long until a few insidious Copy Writers ambushed her, made her drunk with Longe and Parole and dragged her into their agency, where they abused her for their projects again and again. And if she hasn’t been rewritten, then they are still using her.

Far far away, behind the word mountains, far from the countries Vokalia and Consonantia, there live the blind texts. Separated they live in Bookmarksgrove right at the coast of the Semantics, a large language ocean. A small river named Duden flows by their place and supplies it with the necessary regelialia.

It is a paradisematic country, in which roasted parts of sentences fly into your mouth. Even the all-powerful Pointing has no control about the blind texts it is an almost unorthographic life One day however a small line of blind text by the name of Lorem Ipsum decided to leave for the far World of Grammar.