Rabu, 04 Maret 2009

Keeping Cooling Towers and Heat Exchangers Clean By Randy Simmons

Filtration Systems Can Reduce Maintenance and Downtime.

To strike an interesting analogy, your cooling tower and heat exchanger is what the lungs and heart are to the human body; when either aren't working properly, it effects other parts of the body and your health suffers. Similarly, when your cooling tower and heat exchanger isn't clean, the heat exchange process doesn't work efficiently and the health of your production and process cooling system suffers.

Process cooling systems that rely on cooling towers to dissipate heat from process cooling water accomplish this by drawing massive volumes of air into the cooling tower as the water travels through the fill material on its way back to the basin. Through the natural evaporative process, heat is dissipated from the water before it reaches the water basin from which it is re-circulated through the chiller then through the heat exchanger and back again (kind of like when you sweat while working and letting the air evaporate the perspiration to cool you down). It is important to realize that cooling towers are gigantic air scrubbers that capture all airborne debris that happen to be floating nearby, and if your system doesn't have effective filtration, the debris can clog the fill and get circulated and trapped in the heat exchanger where it can build-up, restrict water flow and cause your process equipment to malfunction due to overheating.

An example of this is illustrated by a major automotive assembly facility that had faced periodic downtime due to their robotic welding systems not holding tolerances and causing quality problems. After the robotic technicians spent several days trying to initially solve the problem, one of the maintenance workers opened the heat exchanger and discovered that it was impacted with cottonwood seed, insects and other debris - flow had been reduced and the robotic equipment was running hot. Now you might be asking yourself, whey didn't they have some sort of filtration equipment? The answer is simple; at the time the facility was built, the ambient conditions in that area didn't require a filtration system. However, as the years went by and the area became more developed and cottonwood tree populations grew, the need eventually surfaced.

The interesting thing to note about this situation is that even though cleaning the heat exchanger got the robotic welding system back on-line and running at peak performance, it didn't solve the problem. In fact, cleaning heat exchangers is like taking a cold capsule to relieve the symptoms of a cold. Unless you treat the root cause of the problem, the cooling system will suffer time and again. The root cause in this case and in most heat exchanger fouling situations is the cooling tower - stop the debris from getting into the cooling tower and it will protect the entire process cooling system including fill, cooling water, chiller and heat exchanger. With the proper filtration technology, your process cooling system will stay clean and running efficiently all season long.

Selecting The Right Filtration System

It is important to realize that optimizing the ecology and operational efficiency of your evaporative cooling system is best accomplished by combining a chemical treatment regimen with some type of filtration. The reason is that chemical treatment specifically targets suspended solids and particulates of 40 microns and below, while filtration systems are designed to stop larger debris, especially the kind that causes system clogging and fouling.

For cooling tower filtration, there are two general technologies: Water Based Systems for which there are a few different variations and Air Intake Filtration Systems. With water-based systems, the choices include basic water strainers that remove debris by simply passing water through a mesh strainer; sand filtration systems that remove debris by passing the water through sand and centrifugal separators that spin the water and remove the debris through centrifugal action. In contrast, Air Intake Filter Systems remove the debris by filtering the air as it is being drawn into the cooling tower, keeping the debris out of the system in the first place. When considering your filtration options, the following questions should be asked.

  • What is the cost associated with downtime due to heat exchanger or cooling tower fouling or clogging? (Knowing this will help you justify your filtration system cost)
  • What type of debris is most problematic (can you see it or is it microscopic)?
  • Specifically what part of the system does the filter protect?
  • Which system provides the greatest filtration surface area (this can directly impact frequency of cleaning - the smaller the filter the more frequently it needs cleaning)
  • Can the system be installed without shutting down the cooling tower? (If the cooling tower must be shut down for installation, you need to factor lost productivity into the cost of your filtration system if it's not being installed during shutdown periods.)
  • What is the cost associated with both the filter and installation?
  • How easy is the system to install and maintain?
Answering the above questions will help you to fully understand your options and to make the best choice for your operation.

In the case of the automotive manufacturer, the solution they selected was the Air Intake Filter system. The reason was that they needed a system that would protect their entire process cooling system including fill material, cooling water, chiller and heat exchanger. When they evaluated water-based systems, they discovered that the options provided varying degrees of protection for the chiller and heat exchanger but didn't protect the cooling tower where the root of their problem was. If they had selected a water-based system, their cooling tower would have still drawn airborne debris into both the fill and water where the water filter would have captured the debris before it circulated throughout the system. From a maintenance standpoint, that would have solved the heat exchanger problem but it would have done little to reduce maintenance on the cooling tower. Further, when they compared the cost of water based filtration versus air intake filtration technologies, Air Intake Filtration was found to be the more cost effective approach for their operation.

If you are not currently using a filtration system as part of your process cooling system, then any filtration technology will give you more protection than you have now, however, selecting a solution best suited to your operation requires that you know what kind of debris is the problem and where it is getting into the system. As a rule of thumb, " don't select a small debris solution to solve a large debris problem". Conversely, "don't select a large debris solution to solve a small debris problem". There is clearly a place for both water based filtration and air intake filtration - be sure you're selecting the right filtration for your specific need.

If you are looking to protect only your chiller and heat exchanger from airborne debris, then one of the water-based filtration technologies in combination with a good water treatment program can help you manage the debris that gets into the cooling water. If on the other hand, you're looking for full process cooling system protection, then you should look at Air Intake Filtration - It will stop the debris from getting into your system in the first place.

Air Solution Company developed and patented the first Air Intake Filter specifically engineered to mount to the outside of cooling towers and other HVAC equipment for purposes of stopping the debris before it entered into the system. Since that time, Air Solution Company has been manufacturing and has introduced a variety of other innovative filter systems including its new Fine Mesh Filter which is engineered for use on small and medium size refrigeration coils and machine fan intake housing units. Air Solution Company Randy Simmons is with Air Solution Company, author of articles can be reached at http://www.airsolutioncompany.com

Professional Heating and Air Maintenance By Budda Oliver

Your home's central heating and air conditioning unit, or HVAC, is a key element in your home's energy consumption and comfort level. For these reasons, it is important to have your home's system routinely serviced by a professional technician. It is recommended that your it should be serviced by a qualified technician once every one or two years, depending upon your region's climate and your home's size, age, etc.

It is important to choose a qualified, dependable heating and air specialist to perform any required maintenance of your HVAC system. Having an experienced service technician evaluate its performance is the only way to ensure that your central heating and air conditioning is running efficiently and safely. Keeping your home's system properly maintained will extend your equipment's life and improve the capacity the system can handle. Here are a few things to be sure that your hired service technician should perform.

Any qualified service technician should thoroughly inspect your complete HVAC system. A comprehensive inspection should be made of all elements including cooling coils, primary and secondary drains, blower components, condenser coils, electrical connections, heat exchanger and burners, all safety controls, heat anticipator settings, as well as your system's thermostat and all its included components. After inspection of all these elements, the technician should replace, repair, tighten, adjust, and/or clean any of these components as needed.

A standard scheduled professional maintenance should also include the cleaning or replacement of any air filters found in your home. The technician should lubricate all moving parts incorporated in your home's HVAC system, as well. Freon should also be added by the technician when deemed necessary. If needed, your unit's airflow should be adjusted to ensure efficient temperature rise or decrease. All debris should also be removed from your outdoor condenser unit.

While the heating and air service professional is at your home, he or she should monitor the amperage and voltage draw on all motors, air conditioning and heating cycles, flue draft, and air conditioning operating pressures to ensure proper refrigerant charge.

It is important to have a professional service technician perform scheduled maintenance on your home's system. Qualified A/C techs require the necessary tools, skills, and experience to keep your home's A/C running efficiently, avoiding costly repairs in the future.

Mr. Oliver is a marketing agent of Arundel Cooling and Heating. The heating and air conditioning contractor provides HVAC services throughout Maryland. For more information on their Heating and Cooling Contractors please visit their website.

Tankless Water Heaters - How They Function By Scott S. Rodgers

Water heaters are being used all over the world for a good number of years. The most common one, tank-type storage water heaters function very well and are still pretty common but their major drawback is the large space they occupy. Another disadvantage was the energy loss in them even when the water isn't being used. To solve these two issues, manufacturers have come up with tankless water heaters. This article is meant to provide you with some basic facts about tankless water heaters.

The main concept behind these heaters is provision of hot water on demand only. There exist multiple kinds and they're capable of using different kinds of energy sources to warm water up: from electricity to gas. Because these types of hot water heater do not use a tank, they only warm water as it is needed. The main component is a heat exchanger that gets switched on whenever the connected faucet or shower is opened. For this purpose, a flow-activated switch is used that detects the flow of water inside the pipeline. Two types of heat exchangers are used usually: gas-powered burner and electric coils. Gas-fired ones, however, are able to heat faster and more efficiently.

Tankless heaters are available in different sizes and determination of the size depends on three main factors: the amount of water that has to be heated in one minute; the temperature of water when it goes into the heater; and lastly, its preferable temperature that you want at the outlet. Unlike tank-type storage heaters that keep water at the desired temperature using a thermostat, tankless heaters heat water on demand; thus the first water that comes out of the spigot after turning it on warms gradually. In this way, you'll have to waste water before the hot water is ready. The amount of time it takes to get hot water after opening the faucet is known as lag time. Two types of tankless systems are available. The 1st is the 'point of use' water heater. It's usually compact and supplies one output site, such as a bath. Since it is installed in close proximity to the water outlet, a point-of-use heater typically has a lower lag time and less water is wasted. Since it is used to supply hot water at a single outlet, electric-powered fire exchangers can do the job quite well. Therefore, most 'point of use' system use electricity and, thanks to their compactness, can be stored inside a small area.

The second type, whole-house tankless water heater, is able to heat a significantly greater amount of water per minute and can cater hot water at various outlets simultaneously. Because they require additional energy to warm great amounts of water, they commonly are powered by gas. For larger houses, you may need more than one whole-house system. Showers typically necessitate addition of another whole-house tankless system because they usually need more hot water than ordinary taps. Due to their extra capabilities, whole-house heaters cost a lot more than point-of-use systems.

Scott Rodgers is a master plumber who has recently begun writing articles for both a plumbing and non-plumbing audience. To view more of plumbing articles, visit http://eLocalPlumbers.com

Heating Water for Domestic Hot Water or to Heat Your Home By Kelly P Kramer

Water is heated for two purposes in residential applications. The first is to heat water for domestic use. Such a cleaning, washing, cooking, showers and bathing. The second is to heat water to be a medium for carrying that heat to a room then releasing the heat into that room to keep us warm.

Water heater| hot water tanks

Heating water for domestic use is done with hot water tanks, tankless water heaters, or indirect water heaters.

Tankless water heaters

Tankless water heaters are becoming more common in North America, although these have been used in other parts of the world for years. This kind of water heater does not have any water in a tank. If you do not have a tank then you will not have to continually keep that water heated as the water will always cool even when not in use. The cooling process is caused by heat from the water warming the air in the flue, then the hot air rises and is displaced by cooler air which is in turn heated by the hot water (convection heat just like baseboard heating). This air will flow up the flue and spill out into the room. Also the water in the tank will cool as heat conducts through the tank and into the room. This cooling process is called standby loss and because of this process your water heater is at best 55% efficient.

Tankless water heaters are more efficient than hot water tanks because of the heating process. A hot water heater will heat the bottom of the tank and the center of the tank, with most of the energy leaving the tank up the flue. Where as a tankless water heater heats a coil of pipes inside of a heat exchanger similar to that of a boiler. This heat exchanger is made up of small tubes that heat up very fast.

A tankless water heater will also modulate the burner. So if you need only a small demand the tankless heater will only give you a small flame. And if you need a larger demand a tankless water heater will give you a larger flame.

Hot Water Tanks

Hot water tanks are the most common form in North America to heat your domestic water. These tanks have been around for a very long time and have not changed much until recently. Most homes use a 40 to 50 US gallon water heater. Between high energy costs and pollution many people are switching to better ways to heat there water.

A hot water heater requires a chimney for the flue gases to flow to the outside (except power vent and direct vent water heaters, these can be piped out the wall). Water heaters also have an anode rod to protect the tank, a dip tube to allow the cold water to flow to the bottom of the tank, a gas valve, burner and a relief valve. NEVER plug a relief valve. This is the largest cause of water heater explosions. Water when heated to boiling changes to steam. When this happens the water expands 1700 times and with no where to go the tank has to blow up. Usually the bottom is what bursts and the water heater becomes a rocket shooting through the roof in a two story building.

For more info got Hot water tanks:

Indirect water heaters--An indirect water heater uses a boiler to heat the water that flows through the inside of a coil of pipe which in turns heats the domestic water through conduction. These are very efficient, have a fast response time and out last a standard water heater more than three to one. The response time is very quick giving you more than enough hot water. In my opinion these are the best water heaters on the market. The biggest problem is that you need a boiler to heat the water therefore the cost can be high compared to a normal water heater. If you are renovating and going to install hot water heating of any sort, such as a fan coil instead of a high efficient furnace, then this is the way to go

Water heating | Heating your home

Heating water to heat your home is best done with a boiler. The reason I say this is that a boiler is meant to heat water in an efficient manner, while your water heat is not. A standard water heater has an efficiency of 65% to 70% including standby losses. A standard boiler runs at about 80%. The boilers I install have an efficiency rating of between 85% and 98% depending on the system and time of year. So you could use a water heater to heat your home (check with local codes), but the lifespan is much less and your heating bill will be much greater. Not worth the $2500 to $3500 difference between the two. (my opinion). You could use a tankless water heater, but you will need two or three if you are heating your domestic water as well. Still compared with a condensing boiler you are only saving less than $1000

Kelly Kramer owns a plumbing company and buy and sells real estate, if you liked this article you can learn more at http://www.edmontons-business-directory.com

What Makes a High Efficient Furnace So Efficient? By Mike Meincke

With today's rising energy demands, volatile financial & housing markets and a constant potential of increased living costs looming over our shoulders, catching a financial break anywhere we can as a consumer should be of keen interest to everybody. 90%+ Annual Fuel Utilization Efficiency (AFUE) furnaces may easily provide the solution and can easily off set a household bill or two with all of the energy being saved by this furnace in contrast to the conventional 60-80% AFUE furnace that is more than likely currently in your home even as you read this article. 90%+ AFUE furnaces have a 2 heat exchanger design to avoid wasting heat, in the past the product was problematic when it was first developed in the 90's, but has since been improved to near perfection today by most manufacturers to be a very reliable product and if sized properly and installed properly will save an incredible amount of money on the utility bill that you can capitalize on year in and year out.

The two heat exchanger design is the key feature that allows a 90%+ AFUE furnace to operate so efficiently. A primary heat exchanger handles the ignition of the furnace and the natural gas fire (propane, kerosene, heating oil or what ever the furnace burns) of the furnace burners. As the burners are engaged inside of the heat exchanger, the heat exchanger gets hot so that when the furnace blower turns on, forced air travels over the hot heat exchanger to allow for heat transfer to occur, sending warm air through your air ducts and to ultimately heat the air in your home. With a conventional 60-80% AFUE furnace that is all that is present for a heat exchanger, but through brilliant engineering furnace manufacturers realized that flue gases always creates hot moisture that is typically wasted out of the flue pipe and so they decided to capture this free energy by designing a better product. So engineers went to work to produce the two heat exchanger furnace and incorporated a secondary heat exchanger that looks like a coil to capture the hot flue gas moisture to re use this heat in a more efficient appliance, rather than wasting this heat out of the flue pipe.

Remarkably after 70 years of relatively little change in the heating market in terms of how a furnace basically operated, a vastly more efficient appliance emerged on the market. Two stage technology emerged as well, where engineers realized that a furnace did not necessarily have to high fire gas at all times to effectively heat your home, due to varying weather outside of your home. The two stage gas valve emerged to where a low fire predominately occurs on temperate (less cold) winter days saving an additional 25-35% on gas consumption and then when the weather gets real cold outside the furnace can engage a high fire to ensure that the appliance can keep up with heating your home only when high fire is truly needed, to ensure that the homeowner gets the best of both worlds; saving money and staying comfortable.

A conventional furnace is missing these features, because the conventional furnace can only fire in one stage and just wastes flue gas moisture out of the flue pipe. The venting of a 90%+ AFUE furnace is typically done with PVC piping material and most often is vented to the exterior side of a home. The 90%+ AFUE furnace burns and exhausts vastly more cleaner gases than a conventional furnace effectively lowering emissions as well, so you can feel good about doing your part in the environment when you have a 90%+ AFUE furnace installed in your home.

Some contractors are afraid to install a 90%+ AFUE furnace in your home due to lack of training and an inability to successfully repair furnaces in the first place. One legitimate complaint and or criticism that was true in the past, that these contractors would make, is that parts were more expensive on a 90%+ AFUE furnace and why on earth would you want an expensive repair bill they would ask. That all came to an end when Rheem manufacturing designed their new line of 95% AFUE 2 stage furnaces. All parts selected to make the Rheem 95% AFUE 2 stage furnace work are of quality durable design, but cost effective to repair after the furnace warranty expires.

This would not be the case with the expensive Carrier induced draft motors and chip boards or the expensive chip boards used by Trane and American Standard or all parts by Lennox being of higher expense in their product lines of 90%+ AFUE furnaces. Furthermore, Rheem realized that the primary heat exchanger was the most expensive part of the furnace, so they decided to make a primary heat exchanger tougher than any other manufacturers primary heat exchanger.

The Rheem primary heat exchanger is constructed of stainless steel and is of a tubular design with virtually no seam points present on the part, kind of like a car tail pipe, which rarely breaks. Eliminating seam points on the heat exchanger increases the life span of the part. On the contrary, the Lennox, Carrier, Trane and American Standard heat exchangers are a cheaper clam shell design that is no where near as strong as the tubular designed heat exchanger. The clam shell designed heat exchanger is designed to last a certain amount of years, but once enough time goes by these heat exchangers typically fail due to 4 sides of crimped seams separating the heat exchanger, leading to part failure.

Not only is the Rheem 90%+ AFUE line of furnaces tougher and built with cost effective parts in mind, but they even went as far as ensuring that all Rheem furnaces operate at a vastly lower decibal range making the Rheem furnace the quietest class of furnaces in the residential market today. Carrier, Trane, American Standard and Lennox furnaces will work and if sized and installed properly will last for many years, however when they break, you will surly pay a pretty penny to get them fixed.

When you call out an HVAC company or contractor to perform an in home estimate to install your 90%+ AFUE furnace, make sure that they are evaluating your whole house. Proper furnace sizing will involve an estimator to evaluate wall insulation type, attic insulation type, home exposure, window type, slab type, outdoor landscape, fire places present, duct sizing, how many people occupies the space as well as a few other factors too.

Be leery of the estimator that is in and out of your home in 30 minutes or less, because getting it right during the estimate phase will have a huge effect on achieving maximum efficiency of the furnace and your over all indoor comfort for many years to come. Most of the estimates that reputable heating and air conditioning companies perform may require between 1-2 hours to gather all necessary data, answer customer questions and to write an up front price to do the work.

There are many like minded good companies and contractors out there that conduct themselves that way as well. Your best bet would be to just call out an ACCA member company to perform the estimate, because an ACCA member company will operate professionally, follow higher HVAC standards and receives accredited support in training, up to date trade information and will be up to date with new techniques and standards in the HVAC field. Visit www.acca.org and use the contractor zip code locator to find an ACCA member company near you.

Article By: Mike Meincke. Managing Member of Lucky Duct, LLC. http://www.luckyduct.net.

Mike Meincke is the Managing Member of Lucky Duct, LLC. Lucky Duct, LLC is a full service heating and air conditioning company that operates in the Denver metro market. Lucky Duct, LLC also provides commercial and residential air duct cleaning services using the most powerful equipment in the industry. Mike Meincke is personally licensed for HVAC as a licensed HVAC Supervisor, is EPA certified for refrigeration, has attended numerous manufacturing training courses with Rheem, Goodman and American Standard and has a decade of hands on experience in the HVAC field.

What is Fan Coil? By Johnson S. Kuan

Fan coil is an air conditioning unit. Its main components are coil and fin heat exchanger, fan, drain pan. If you pump chilling water into the heat exchanger, then the fan will send out cool air, If you pump hot water into the heat exchanger, the fan will send out warm air.

Big buildings are suitable to install fan coil units, such as: Air port, hospital, office building, hotel, department store, school, factory...

There are ceiling concealed type fan coils, floor cabinet type fan coils, cassette type fan coils, and ductable type fan coils. The ceiling concealed type fan coil is installed above the ceiling, it is also needed to install supply air outlet, return air inlet and air duct connecting to these inlet and outlet. The floor cabinet type fan coil is usually installed along the window, so that its supply air can warm the window in Winter, then the window can get rid of the condensing water problem. The cassette type fan coil is installed on the ceiling of the big hall where there are a lot of people coming in and out. The ductable fan coil is somewhat like the ceiling concealed type fan coil, but its air volume is bigger and its static pressure is higher.

Fan coil is also needed to install inlet and outlet cooling/heating water pipes and a condensate pipe. And it also needs to install a solenoid valve on the water pipe, this valve is controlled by a thermostat, then the air conditioning room's temperature can be set to a desired temperature.

Before ordering fan coil please make sure the following items:

1) Cooling / Heating capacity,
2) External static pressure for ducting,
3) Hand side of water connection,
4) Power source.

For more information, please check: http://www.fan-coil.cn

A HAVC engineer having been producing all kinds of fan coil units and air handling units for dozens of years.

Goodman Heat Pumps - The Paragon of Quality Heating By David Karlson

Goodman is widely known to be the second largest manufacture of Air conditioners used for residential purposes and heating systems in Northern America. Goodman Heat Pumps is one of the most famous lines of Goodman brand.

Here is a list of some of the fabulous products promoted by Goodman Heat Pumps:

  • dedicated Horizontal 13 SEER GPH13H
  • Multi-position 13 SEER GPH 13M commercial
  • Multi-position 13 SEER GPH 13M international
  • Multi-position 13 SEER GPH 13M
  • 16 SEER SSZ16
  • 14 SEER SSZ14
  • 14 SEER GSH13
  • 13 SEER GSH13
  • GSH commercial products
  • GSH international products

The total package of Goodman Heat Pumps includes the following:

  • A compressor or motor unit
  • Air coil
  • A fan
  • A motor
  • A heat exchanger

Goodman Heat Pumps can also work as a superb refrigerant. A refrigerant is known to be a substance that facilitates heat transfer.

These are a gas and tend to result in condensation as these make their way in to the air coil. The air coil technology is widely used to manufacture these pumps.

One of the best things about Goodman heat pumps is that these also include geothermal heat pumps. These are known to be more efficient as compared to the other types of pumps. The logic behind the greater efficiency is that during winter, the soil temperature is warm. The air source heat pumps tend to move heat from cold outside in to the inside and this in contrast makes it quite hard to function.

Goodman Heat Pumps network has its' distribution points over 700 different places. The distribution points are located in the following centers:

  • Texas
  • California
  • Florida
  • Nevada
  • Arizona

When it comes to the types Goodman heat pumps available on the market, these days there are in abundance. Hence, there will be one for everyone's requirement.

The best part is that they also manufacture supreme quality air conditioner systems.

Many customers had some wonderful experiences with Goodman heat pumps. All these people are extremely happy with the performance, quality and supremacy of the brand. The products are reliable and the best part is that these are available at a lower price.

The company is also eminent for its wonderful gas fireplaces, coils and air quality products. In case, you have already decided on purchasing Goodman heat pumps, you must know about what is included in the purchase.

A total purchase of a quality of a Goodman heat pump, here is what will be included in to the package:

  • A heat exchanger
  • An air coil
  • A compressor.

The air coil is a large element and utilized for the purpose of condensation. The refrigerant facilitates heat transfer and save a lot of money on the energy bills.

We provide information for the consumer on heat pump prices along with information on specific brands such as Goodman heat pumps.

http://www.heatpumpsrus.com

By D. Karlson