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Most of today's new homes are highly insulated and practically air tight. While this is great as far as cost effective energy bills go, the down side to tightly insulated homes is poor indoor air quality. As windows and doors are typically kept shut throughout the day, moisture, and stale air that can carry contaminants and pathogens circulates inside homes and gives rise to various problems including mold and mildew, health problems, ruined furniture, peeling paint etc. This is why it is important that you take every step to improve the quality of your indoor air, which can be achieved through mechanical ventilation.
An excellent way to ventilate your home thoroughly, efficiently, and cheaply is to install exhaust fans in your home. This article explains what exhaust fans are, their different types, how to select the best one for your home, and also the benefits of exhaust ventilation fans.
What Are Exhaust Fans
An exhaust fan is a mechanical ventilation device that helps to draw out stale and impure air from your home and bring in fresh air, thereby improving the quality of indoor air. Exhaust fans are typically ducted to the exteriors of your house, through which bad indoor air can effectively be removed from your living space.
Types Of Exhaust Fans
Exhaust fans are classified into various types, mainly depending on the type of mount and the location where you need to install the fans. The different types are:
1. Ceiling Mounted Exhaust Fans: As the name suggests, ceiling exhaust fans are those which are installed in the ceiling. Such fans expel stale air from your home upwards through the roof. The fan is connected to ducting, which is exhausted outside the home via an external vent, like a roof cap or soffit exhaust vent.
2. Inline Exhaust Fans: Unlike ceiling exhaust fans that are installed directly into the ceiling, inline exhaust fans are typically mounted in-between ducting, hence the name inline fan. For instance, if you wanted to ventilate an area that did not have clearance or space for a ceiling mount fan, you would make use of inline exhaust fans to ventilate such areas. The exhaust fan would be placed in between the ductwork and the stale air would travel through the ducts and ultimately be expelled from your home. Since inline fans are not mounted directly to the ceiling, they are very quiet. When installing an inline fan, to reduce noise, we recommend using an insulated flex duct that is at least eight feet long from the intake port on the ceiling to the inline fan.
Inline exhaust fans are ideal for exhausting areas or rooms where you cannot, or do not wish to install the exhaust fan directly. Since these types of exhaust fans are mounted in remote areas, they are also referred to as remote mounted exhaust fans. Inline exhaust fans can either be single-port (exhausting from a single area) or multi-port (exhausting from multiple areas).
3. Wall Mounted Exhaust Fans: These exhaust fans are installed on walls. Since they are installed on exterior walls of the home and not on interior walls, the stale air has a direct route to the outside of your home and thus no duct work is required in installing these exhaust fans.
4. Combination Exhaust Fans: Exhaust fans are also available as combination units. You have the choice of a fan-light combination where the exhaust fan provides illumination as well, or heat-fan-light combination wherein you get a heater, light and ventilating fan all in a single device.
5. Exterior Remote Mounted Exhaust Fans: While most other exhaust fans are installed inside your home and push stale air out, exterior remote mounted fans are installed outside your home and pull out stale indoor air instead of pushing it out. The main benefit of these exhaust fans is that regardless of however noisy they are, most of the noise remains outside your home.
6. Kitchen Range Exhaust Fans: These fans are mounted inside the range hood over your kitchen stove. Such fans not only help to rid your kitchen of stale air but also help to expel bad odors and reduce moisture levels in your cooking area.
These several types of exhaust fans can be used for complete ventilation of your home including intermittent local ventilation for baths, kitchens, dryer rooms; continuous whole house ventilation throughout your home, and for exhausting hard-to-air spaces such as crawl spaces, attics, and basements.
Benefits Of Exhaust Fans
Exhaust fans are very effective at ventilating your home and other living spaces. Without proper ventilation, the air inside your home can get filled with harmful contaminants and disease causing pathogens.
Pollutants such as pesticides, harmful gases, smoke, pet dander, lead, asbestos, dust mites, paint fumes, grease etc get released into indoor air due to daily activities such as cooking, smoking, burning fuel, bathing, renovating etc. In addition to these pollutants, activities such as bathing, cooking, and washing also release excess moisture in the air and make indoor air extremely humid. If not ventilated adequately, these added pollutants and increased moisture levels can decrease the quality of indoor air greatly, thereby leading to various problems such as:
Health problems including asthma, allergies, nose bleeds, skin rashes, headaches, nausea, and other breathing disorders. In fact, according to the Environmental Protection Agency, a large percentage of the over 20 million annual asthma cases in the US alone can be attributed to bad indoor air quality.
Split, warped and rotted furniture due to excess humidity.
Cracked and peeling paint on the walls.
Formation of fungus, mold spores, and mildew, which in turn lead to severe health problems.
Thus, by using exhaust fans to ventilate your home efficiently and completely, thereby improving indoor air quality, you can rid yourself and your home of all these problems.
Recommended Sizing Of Exhaust Fans
To ventilate your home effectively, it is important that the exhaust fan you choose has the capacity to exhaust the intended space completely. To ensure this, you must select the right sized fan for your needs. Here's a look at how to size exhaust fans properly.
1. Location of the Exhaust Fan and Air Changes Per Hour:
Where you intend to install the exhaust fan will have a direct bearing on its size. As per the Home Ventilating Institute (HVI), different locations in your home require varying Air Changes Per Hour (ACH) in order to be ventilated properly. Here are the ACH requirements recommended by HVI.
8 ACH for bathrooms
15 ACH for kitchens
6 ACH for rooms other than bath and kitchen
ACH refers to the number of times the air should be completely changed in an hour. Thus, an 8 ACH recommendation for bathrooms means the exhaust fan should have the capacity to completely change the air in the bathroom 8 times in one hour.
All exhaust fans are rated in CFM, which refers to Cubic Feet per Minute. To determine how large an exhaust fan you need (in other words, CFM rating of the fan) here's what you need to do.
Sizing Bathroom Exhaust Fans:
First and foremost, measure the dimensions (length, width, and height) of the room and then calculate the volume of air in the room by multiplying all these 3 numbers. For instance, if your bathroom has dimensions of 6 x 10 x 8, then the air volume in the bathroom is 480 cubic feet. Thus, the exhaust fan needs to ventilate 480 cubic feet of air in order to achieve 1 ACH. But since the recommended ACH for bathrooms is 8, the fan will effectively need to ventilate 480 x 8 cubic feet, which equals 3840 cubic feet in one hour. Fan ratings are per minute, thus by dividing 3840 by 60, you can achieve the desired CFM rating for the fan which in this case is 64.
A simpler way of determining the CFM rating for bathroom exhaust fans is to simply multiply the length of the bathroom by its width. For every 1 sq. ft. of floor area, you need 1 CFM. Thus, in the above example, area would be 6 x 10 = 60, thus recommended fan size would be 60 CFM.
However, if your bathroom is more than 100 sq. ft. in size, you have to add the different fixtures in your bathroom to reach the desired CFM rating. The recommended CFM for different fixtures is:
· Shower - 50 CFM
· Toilet - 50 CFM
· Bathtub - 50 CFM
· Whirlpool tub - 100 CFM
Thus, if your bathroom is more than 100 sq. ft. in size and has a toilet and shower, you will need an exhaust fan with 100 CFM rating. If a bathtub is also present the CFM rating will increase to 150 and so on.
Sizing Kitchen Exhaust Fans:
When sizing an exhaust fan for the kitchen, you have to take into account the location of your kitchen cooking range (if without range hood) or the size and location of the range hood if there is one. Here are the recommended CFM ratings for kitchen range hood exhaust fans:
Generally speaking, for every 10,000 BTU of the range, it is recommended a minimum of 100 CFM. So if your range is rated at 50,000 btu's, you would consider getting a fan with at least 500 CFM.
2. Understanding Static Pressure and Measuring Equivalent Duct Length:
When sizing an exhaust fan that does not open directly to the outside but is ducted, it is important to ensure that the exhaust fan has the capability to move stale air throughout the duct and ultimately to the outside. Here, we first need to understand what static pressure and equivalent duct length is.
Static Pressure: Inside every duct, there is a constant pressure being exerted at any point from all directions. When an exhaust fan moves air through the duct, the air counters resistance from this pressure which is known as static pressure. Thus, an exhaust fan has to have the ability to overcome the static pressure in a duct so as to effectively duct stale air to the outside of your home. This can be done by calculating the equivalent duct length of any duct.
Calculating Equivalent Duct Length (EDL): Simply measuring the length of a duct is not enough to know how much static pressure an exhaust fan has to overcome. Ducts may have one or more elbows, turns, or wall caps which add to the static pressure in a duct. Thus, you have to calculate the equivalent duct run and not the actual duct run so as to size an exhaust fan properly.
The static pressure in any duct run differs according to the material of the duct, number of elbows and turns, exterior wall cap and wall jacks etc. Listed below are the standard values for different duct components.
Smooth metal duct: Actual duct length x 1
Flex aluminum duct: Actual duct length x 1.25 (for 4"diameter duct)
Actual duct length x 1.50 (for 6"diameter duct)
Insulated flex duct: Actual duct length x 1.50 (for 4"diameter duct)
Actual duct length x 2.00 (for 6"diameter duct)
Wall caps and roof caps: 30 feet for each cap (for 4"diameter duct)
40 feet for each cap (for 6"diameter duct)
Elbows and turns: 15 feet for each (for 4"diameter duct)
20 feet for each (for 6"diameter duct)
Using the above values, you can calculate the equivalent straight duct length that an exhaust fan has to overcome so as to push stale air outside your home and counter static pressure effectively.
This ventilation guide is provided as a service from R.E. Williams Cont. Inc. Please be aware, that building codes and local regulations differ from region to region, they also can change.; therefore, R.E. Williams' Cont. Inc. assumes no liability for omissions, errors or the outcome of any home improvement project. You should always exercise reasonable caution, follow your current codes and regulations that may apply, and if in doubt on any procedure consult with a licensed professional.
For a complete line of residential ventilation solutions, visit our website at
www.REWCI.com
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The soaring price of gas is putting a crunch on pretty much any blue collar guy lately and has a lot of us becoming very interested in alternative fuels. There was time not very long ago that I was not happy unless my truck had two fuel tanks and enough power to pull down a house. Now a moped is looking pretty good and I don't even think about picking on people for riding them anymore.
One of the most popular gas saving techniques out there right now is the Water For Gas system where you build your own HHO system. I started trying this system out a few weeks ago and so far I am happy with the progress I have made.
The first thing that I built was one of the HHO electrolyzers which was not very hard but it does require some mechanical know how. If you are the type guy that works on your car yourself then it should be no problem for you to build. Pretty much their whole target audience for the build it yourself HHO products are the blue collar guys that are used to working with their hands and have some mechanical know how.
Installing the Electrolyzer was even easier than building it. Hook up a vacuum line and a few wires and you are done. I did add in a relay so that I could actually power the generator straight from the battery. You just need to find a wire that is only hot when the engine is running and use that to power your relay.
I did not really time myself but after I had all of the parts together it probably took about three hours for me to put the HHO generator together. It took more time running around town finding all of the parts than what it took to assemble it. There is also a variety of different conductors that you can use to make the plates out of. Stainless steel wire or plates works pretty well and is what I use but there are also designs that are using titanium and copper.
With the fuel injected vehicles you also need something to lean out your fuel mixture so that you will actually save gas. There are two ways of doing this that I know of. The first one is a Map Sensor Enhancer and the second is the EFIE, Electronic Fuel Injection Enhancer.
The Map Sensor Enhancer allows you to manually adjust the voltage reading between the Map sensor and the ECU. It is a fairly simple circuit with a couple of potentiometers, switches, and resistors. If you have a little electrical experience and can read a schematic then this thing is not a big deal to make. Using one of these enhancers allows you to manually lean out your fuel mixture.
While I see why this is needed I would recommend that it should only be installed on a vehicle where the driver knows something about engines. There are quite a few people driving around that have no business being in control of the fuel to air ratio for their vehicle. It is also important that the HHO generator is running when this is used. The water vapor that is produced after burning the HHO gas has a cooling effect on the engine and exhaust system. If you lean out the fuel and do not have the additional cooling then you could do serious damage to your engine or exhaust. The major reason that I thing the driver should know something about what they are doing.
The EFIE device is a bit more complex animal. It involves a circuit board containing diodes, capacitors, resistors, pnp switches, and integrated circuits. I was going to try and build one but radio shack did not carry the IC that I needed for it and I have not bought the stuff that I need online yet. From looking at the schematic though you will need a fair amount of electronic experience to tackle this job.
The EFIE is there to perform the same function as the Map Sensor Enhancer, which is to lean out the fuel mixture, but this device ties in with the O2 sensors instead of the Map. I have not installed one of these myself yet but the installation is very basic, just a few splices. It is building the thing yourself that would get complicated.
That pretty much covers the major components of the Water for Gas HHO System although there are a few smaller items such as PCV valve enhancers and fuel heaters that they recommend.
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Buying a used golf cart can be a very confusing undertaking. There are many variations and types of carts available these days, from the very basic to wildly modified. Buyers have many options, but caution should be used to ensure you don't inherit someone's albatross. Knowing what to look for, could save big expenses later. The first decision to be made is whether you want a gasoline or battery powered cart. Each has its strong and weak points. Gasoline powered carts can be more powerful, making them well suited for utility service or hauling loads. They do consume the precious fossil fuel though, and can be noisy with an undesirable exhaust odor. Battery operated carts are stealthy quiet and odorless, but have a limited range between charge cycles. When the batteries are drained, you're done until they can be recharged, which can take 8 hours or more. After you decide which fits your needs the best, and you've found the candidate, determine if it is really what you are looking for. Know what you are buying before you write that check.
Tire Wear - Take a general assessment of the tires and their condition. Are they all the same brand and do they have similar and even wear? Uneven wear can be indicative of serious alignment problems, a bent frame or worn out steering components. Tires of mixed brands is an indication that the cart may have seen excessive use or be a rebuild of junk parts. This may not necessarily be the case, but keep it in mind as you continue looking over the candidate cart.
Steering - Never buy a cart without taking some time to drive it. Take it over some rough terrain as well as a solid concrete driveway. Sloppy steering should be an immediate concern for you. Worn "rack and pinion" steering boxes are expensive to replace. If the rack and pinion is worn, you can also reasonably expect the steering "rod ends" and spindle bushings also need attention. None of these components are necessarily cheap to replace. The steering wheel, pulling to the left or right can be caused by uneven pressure in the tires or unmatched sizes. If the cart pulls, check the tire pressure first to see if the problem corrects. If it does not help, the spindle (on the same side that it pulls to) may have a bad wheel bearing causing dragging. You can jack up that corner of the cart and see if the wheel rotates freely.
Battery age - Most golf cart battery manufacturers stamp the date of manufacture on the top of one of the battery posts. You can easily see a "08" or "09" etc, even with the battery cable connected. Be aware that batteries that are more than three years old will require replacement sooner than later. Expect to pay 0 or more for a new set of batteries, no matter what the configuration or voltages are. Never assume that the batteries are of the same vintage as the model year of the cart either. Also, batteries of mixed years in the same cart could be a clue that the cart has seen some serious use in a fleet environment.
Brakes - Be sure the brakes are firm and stop the cart quickly without grinding or squealing. Brake shoe replacement is not usually a big deal unless service has been neglected to the point where the brake drum is gouged or otherwise damaged. Excessive rust and corrosion around the brake backing plates behind the rear wheels can be an indication of possible neglected maintenance.
Integrity of the frame - Steel frames are very susceptible to rust and corrosion, especially under the battery compartment. I have seen carts that otherwise look great, actually break in half due to battery acid seeping on, and eating the frame. Some manufactures, like Club Car, are now using fully welded aluminum frames which do not rust, but are still susceptible to corrosion in the form of aluminum oxide (instead of iron oxide). Corroded aluminum has a heavy layer of white fuzzy powder, which is equivalent to rust. Stay away from any cart that you suspect has a frame problem. The cart could end up being totally useless to you later.
Smooth ride - A well maintained cart should roll along smoothly and quietly. A wobbling or lumpy motion when driving on a smooth solid surface indicates a problem. A bent wheel, or worse, a bent axle will cause the cart to bob up and down with a frequency proportional to the speed. An "out of round" tire can also cause a similar symptom but is usually not the case. Worn front end components will exaggerate the symptoms dramatically.
Wiring - Wiring should be neatly routed and protected from chaffing with factory clamps and terminations. Be wary of modified wiring if it does not look professionally done. Cobbled up wiring can cause you big headaches if you are not savvy with electrical systems. A shorted wire on an electric cart can be devastating. The tremendously high current capability of the batteries can turn a shoddy wiring system into a giant cigarette lighter. Look for splices and taped up connections that do not seem to belong, and then pass on the purchase.
Odd Noises from drive train - Turn off any radios and the like when you take your test ride. Listen for any odd noises that may be present. Grinding, excessive whining or clicking sounds can help you identify problems with the cart. The sounds a vehicle makes can tell you quite a bit if you take the time to listen.
Gasoline engines - Be sure to look at the engine. Although you may not be an engine mechanic, you can still evaluate a few things easily. Gross saturation of the engine with oil and grease probably indicates a leaking crankcase or gearbox, or worse, a cracked crankcase or gearbox. Check for large amounts of sooty residue in the exhaust pipe, which is indicative of an oil burner (worn out piston rings). Be sure to let the engine warm up before you take a test ride. An engine will only reveal if it smokes a lot, after it is sufficiently hot. Take your time and check it out. Popping sounds in the exhaust or backfires can be caused by poorly adjusted carburetors, but more commonly by burned intake or exhaust valves in the engine. An engine rebuild can cost you dearly if you need one down the road. Be sure to give it the appropriate attention.
A well maintained cart can literally offer decades of reliable service. Taking time to select the right cart to fit your needs now will pay dividends later. After you purchase your cart, visit some of the vendors that offer great aftermarket products to personalize your vehicle. If you want to speed up your cart a little, visit Digital Overdrive Systems on the web for some more great tips.
A common problem that commercial truck drivers have is a limited amount of space when backing into loading docks. Many times these drivers will bump the dock while trying to maneuver into tight spaces. This most frequently happens from the blind side of the truck while backing.
There have been recent technological advances that are available to truck drivers that can help to eliminate damage to docks, trailers, or trucks while backing. Truck drivers can now purchase rear object detection systems that will alert the driver when objects get within the set distance of the back of the truck.
The rear object detection systems use either radar or sonar technology to transmit a signal to sensors that are placed on the rear of the vehicle. The sensors can be adjusted to the driver's preference with a normal maximum of 10 to 20 feet of detection.
These systems typically become operable either when the vehicle is placed in reverse or as the ignition is put into the on position. There are some issues with the use of these systems though. The sensors are normally placed in the rear of the trailer and the display unit will be located in the cab of the truck. These units will need to be used together and the display units are not interchangeable with the sensors. This limits the amount of driver that will be able to use these units to drivers that exclusively use their own trailers. If a driver were to use another trailer that was also equipped with the sensors the unit would not work properly.
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With an improved airflow and a revised engine management parameters executed on a stock bottom end will significantly increase the power. The all new 1.8T is the new essence of efficiency, functionality and potential. It has a VW tunable engine and the good old Beetle's 1600cc air-cooled boxer.
If you are looking for a more turbocharged engine and planning to increase its power by half or more, then the new 1.8T is the answer you are looking out for. There are two main reasons - one that the 2.0T is still difficult for any modifications for its direct-injection technology and one-piece manifold assembly. And the second factor is that all the parts that are required for adjusting the chassis or the power level for the 1.8T model are readily available in the market from number of sources.
The 1.8T equipped with B6 has been for more than a year and half. It is a mirror image of its sister car, assembled by Stasis for the sports car revolution. These modifications can also be adapted to B5 A4 and B6 A4 versions of Audi.
The most critical modification to this project is the chassis and suspension setup. All of the parts such as springs, dampers, brakes, differential and anti-roll bars are completely interdependent. All these components are then assembled together to give maximum performance at the prescribed OEM level. Stasis has planned to provide complete solution for the different driving conditions. From hot laps of the racing tracks to the everyday street roads, this complete set works the same. The system Stasis developed concentrates on all the mechanical parts giving a perfect balance to the car which in other cases is not possible as only one or two main areas are concentrated.
Suspension modes consist of hyper co-liner coil springs wound to double-adjustable dampers in the front and single adjustable dampers in the rear. The springs and dampers are coupled with an anti-roll bar in the front and a hollow bar at the rear. For this particular arrangement, the spring rates were maintained in the middle of the rigidity medium (700 lb/in in the front, 1000 lb/in at the rear). This has improved the rigidity and performance of the car which offered a spirited driving sessions. The hydraulic charges Ohlin's dampers are compression adjustable coils that can be fine tuned for quality ride and for a perfect steering response. The whole system is run on the new 8x18 inch work emotion CR wheels which are wrapped in
Conti sport contact 2 tires.
The brakes here used are now almost found in few other cars. The system uses the Goodridge braided stainless lines and Alcon hardware. The front wheels are equipped with calipers which have four-piston mono blocks and 14-inch full floating discs. Friction is provided by SBS carbon-ceramic pads. The rear wheels are fitted with two-piece 12 inch rotors, stock calipers and Ferodo DS 2500 pads.
The engine has been over worked with the Stasis stage - III plus turbo upgrade which pushes this 1.8T into the 300 hp realm. The upgraded system contains a cast Inconel manifold, Garret GT28 turbocharger, a front-mount intercooler and supporting hardware including new fuel injectors. Along with this system, the management has been enhanced through the Stasis developed engine management software. The back pressure has been reduced with the use of high-flow-cat-black exhaust pipe.
Modifications along the driveline also include new center and rear differentials. The center differential is a Torque sensing unit, which directs the torque to either the front or rear depending on where it is most needed. Diving into a corner hard on the brakes will yield more power directed to the front. Coming out, hard on the acceleration, the balance will shift to rear wheels via the torque sensing differential unit and the new limited slip differential on the rear axle.
Though the packages are available individually, the best deal is to opt for the complete package. The top level of the package offers the Ohlin's suspension, turbo upgrade and limited slip rear differential.
The company has recently launched its "Signature collection" providing tuning options to the Audi A4 and A3 series. The signature collection comes in with two packages. The touring series comes with the increase in power, increased suspension spring rates, digressive damper valves, 19 inch forged wheels and bigger brake rotors. The challenge series takes a step further which includes the touring series along with added features of DTM aero kit, a high bias Torsion central differential, more engine power and torque. Though the package comes out at ,000 for the touring series, it is far less when compared with the products purchased individually. Guess what, you even get a 4 year/50,000 mile warranty to this package. That's something you won't see a lot of aftermarket outfits offer.
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Hello and welcome back to our series on automotive tools and how to guides for the new weekend warrior auto mechanic. This isn't meant for the professional, but rather the average Joe who is looking to get his hands a little dirty on the weekends. In the past, we have covered a lot of tools but in today's article I'm going to cover what it is that your car's exhaust is responsible for. Your car's exhaust is a central part of your vehicle as long as you intend to keep it street legal. If you have been following along with our articles, you know that air and fuel is mixed and combusted in the combustion chamber of your engine. From there it travels to the exhaust system.
In most exhaust systems, the spent fuel's journey will begin at the exhaust manifold, otherwise known as a header if you have a performance exhaust. While designs vary, they all serve the same purpose of getting the spent gases from the exhaust port down to the catalytic converter. It is here that the exhaust gases combine and interact with the chemicals in your catalytic converter to produce less harmful emissions.
From there the gases travel down the main pipe and to a resonator, muffler, or a combination of the two. The purpose of them is to lessen the amount of noise heard from your car's running engine. Typically a resonator is used in conjunction with a muffler to create a desired "Tone" or sound to the exhaust note. That's all there is to your car's exhaust system. When it wears out, typically there is no repair for them other than complete replacement.
