Tag Archives: hvac

Blower Door Home Energy Audit

Blower door testing is the most practical way to predict energy savings from air-sealing methods.how to do a blower door audit

Compare blower-door operation to inflating a leaky beach ball. When you inflate a beach ball, it doesn’t take much effort to fill it if there are no holes present. If the ball has a few pin holes, you have to apply a little more effort because eventually the air will leak out and the ball will become deflated. If there are holes that are bigger (such as raisin-sized holes), you will have to put forth an incredible amount of effort to keep the ball inflated. The total size of the all the holes and the pressure difference between the ball and the outside determines the rate at which you need to blow air to keep the ball inflated.

Like the blowing pressure of your lungs to keep a beach ball inflated, a blower door pressurizes your home by blowing air in or depressurizes the home by sucking air out. Depressurization, which creates a vacuum indoors, is the most common procedure because air comes in through air leaks, allowing you to feel and locate the air leaks in your home. The combined area of the building leaks and the pressure difference between indoors and outdoors determines how much air the blower door moves. The air flow is measured by CFM (cubic feet per minute). The standard for measuring a home’s air leakage is the air flow through the blower door at 50 pascals of house pressure (CFM50)

Blower door testing involves preparing the home for testing, setting up the blower door in a doorway, connecting the gauges, turning on the blower door, and reading the pressure reading on the gauges.

Prepare for testing by following these steps:

  • Close windows and storm doors.
  • Open all interior doors.
  • Disable heaters and water heaters by turning their thermostats down.
  • Cover ashes in wood stoves and fireplaces with damp newspaper to prevent them from being sucked into the home.
  • Shut fireplace dampers, fireplace glass doors, wood stove dampers, and wood stove air intakes.

The blower door operator should slowly bring the house pressure to 50 pascals. This is usually preset with the blower door gauges before he begins. With the house pressure at 50 pascals, the operator notes the CFM50 number from the digital air flow gauge. Then he begins to look around the home with a smoke generator to help find the air leaks in your home. I promise that you will be amazed to discover where the leaks are and the amount of leakage that occurs.

There are several common factors to help to determine the amount of air leakage you may have in your home. This is a little technical, but it will help you to understand the importance of a test of this nature.

  1. The 50 Pascal Airflow Rate: a blower door reading expressed in cubic feet per minute (CFM50) is the actual flow measured at 50 pascals of house pressure.
  2. The 50-Pascal Air Change Rate (ACH50): a blower door reading expressed in air changes per hour at 50 pascals. This is calculated by multiplying the CFM50 by 60min/hour and then dividing by the house volume in cubic feet.
  3. Natural Air Change rate (ACH natural): natural air change is expressed in air changes per hour.

If all of this seems a bit overwhelming, the home energy auditor in your area will know just what to do with all these numbers and formulas. If you are wondering where to find an energy auditor, check with your local courthouse or utility company. Hiring a home energy auditor will be money well spent!

Top 5 Signs it’s Time to Buy a New Furnace

Furnaces are rugged and durable appliances that are built to perform like champions on even the frostiest January nights.

But over time, your furnace will wear down and gradually wear out. And even if it doesn’t, your needs and expectations may evolve, and a furnace that seemed like a solid, quality performer a few years ago might be less than adequate now.

Of course, getting a new furnace requires a significant financial investment, including installation costs as well as the price of the equipment. Before you lay out that kind of coin, you’ll want to be 100 percent sure the time is right to make a change.

Top 5 Signs it’s Time to Buy a New Furnace

So how will you know when your furnace is on its last legs and just about ready for the scrap heap? Here are five good indicators …

      1. Advanced age

With few exceptions, furnaces in general tend to wear out after 10-15 years of steady functioning, although early and obvious signs of damage or decay may not be detectable. Another factor to consider is that each new generation of furnace is more energy-efficient, and therefore more cost-effective, than the last, and the opportunity to cut your monthly fuel costs by 40-50 percent may be too good to pass up. Despite the upfront costs, a brand new energy-efficient furnace could pay for itself in less than 10 years’ time, depending on the quality and efficiency of the unit it is replacing.

      2. Escalating fuel bills

Have your home heating bills been creeping upward beyond the rising cost of fuel? Progressive changes like this are the mark of a furnace in crisis, and if you don’t take action, the problem will only get worse. By all means, you should consult with your HVAC contractor before making a final judgment, but if they can’t find a single mechanical problem that explains the excessive fuel usage, a general systemic decline is the likeliest explanation.

       3. More frequent services calls for repairs

Repeatedly patching up a failing appliance makes no economic sense. When things reach the point where you’ve got your HVAC contractor’s emergency repair line on speed dial, it might be time to start working on the epitaph for your furnace’s tombstone.

      4. Strange noises, odors, leaks, or soot accumulation

These are symptoms of a furnace that’s gradually crumbling into dust, the forces of entropy and heavy use stressing it to the breaking point. In a sense, these are like the small tremors that often precede a giant earthquake, and they should motivate you to take action before disaster strikes.

     5. Uneven heat distribution

Hot spots, cold spots, and temperature differentials throughout the house could mean one of two things: either your furnace is improperly-sized (too big or too small for your home), or it can no longer kick out and distribute heat at a consistent rate. If temperature anomalies are a new phenomenon, it means the latter is the problem, and that’s a clue your furnace is losing its battle with Father Time.

Energy-Efficient Furnaces are a Johns Plumbing, Heating,  and Air Conditioning Specialty

Johns Plumbing & HVAC is a certified dealer of Trane heating and cooling products, including state-of-the-art gas and oil furnaces that can maximize your fuel-cost savings.

If you’re in the market for a new furnace, or would like to have your old one checked and evaluated, please give us a call today. With our outstanding heating products and superb installation services, we can help you make a smooth transition to a happy new era in affordable home comfort.

 

10 Tips to Prepare You for the Winter Heating Season

Autumn is a time of transition. When the temperatures drop, the winds rise, and the leaves change color, it means air conditioning season is over, and the winter heating season is fast approaching.

10 Steps to Prepare Your Home for the Winter Season

In the coming months, your furnace and/or heat pump will be charged with the task of keeping your family warm and comfortable on even the coldest winter days. But there is more to home heating than just setting your thermostat at 70 degrees and letting it run night and day.

To get the most out of your heating system, you need to pamper it, customize it, and support it with smart home maintenance actions. You should get to work on all of this at least a month or two before heating season arrives to make sure your equipment is ready to function as efficiently as possible right from the first moment you need it.

Here are some pre-winter preparation tips that will put your HVAC system in prime working order and get your home ready for the long, cold months to come:

  • Plug or fill all potential sources of air leakage. Use caulk and weatherstripping to fill in and around windows, doors, pipes, electrical outlets, and other areas where small air leaks can lead to big energy loss.
  • Clean everything. When your home is shut up tight for the winter, your indoor air quality can deteriorate, putting your family at risk for respiratory disorders and other types of allergic reactions. To remove potential sources of contamination, clean your house thoroughly from top to bottom a few weeks before the heating season begins.
  • Inspect your insulation and add more if you find gaps. Attics and basements are areas of special interest. Spray-foam insulation is probably your best bet if you decide to add more insulation, since spray-foam will penetrate and fill cracks, crevices, and small openings wherever they might exist.
  • Check and clean all air vents. Over the course of the summer, your intake and output vents may become clogged with dust, dirt, and other forms of particulate matter. This can restrict air flow and reduce your HVAC system’s efficiency.
  • Add a humidifier to your home comfort arsenal. Humidifiers will help improve air quality, and moist air also feels warmer than dry air, which means you’ll be able to set your thermostat a few degrees lower than normal and still feel comfortable.
  • Reverse the direction of your ceiling fans. They should run clockwise (at low speeds) during the winter, drawing cool air upward and forcing warm air downward. The use of ceiling fans in winter can cut heating costs down by 5-10 percent.
  • Change your HVAC air filter. This should be done on a monthly or bimonthly basis during the winter months, depending on the quality of the air filter you purchase. You should avoid the cheap fiberglass models and look for something of better quality—like a pleated or electrostatic filter.
  • Install double-glazed or low e-glass windows. By adding an extra pane of glass or low-emissivity glass coatings, you can cut heat loss through your windows by as much as 40 percent.
  • Have your ductwork inspected and cleaned or repaired if necessary. Find a reliable duct cleaning company with good online reviews (there are scammers out there, so beware!), and make an appointment to have your ducts checked for leakage and/or excessive contamination.
  • Call your HVAC contractor to arrange a full maintenance inspection of your furnace and/or heat pump. A full inspection and tune-up for your furnace and/or heat pump should be a fixture on your autumn “to do” list.  A trained technician can find and repair small problems before they turn into gigantic mechanical failures, while performing basic maintenance procedures that can restore your equipment to tip-top working order.

 

 

Tips for Reducing Humidity Indoors

North Carolina summers are notoriously hot and humid, but when this humidity gets too high indoors, problems can occur. Recommended humidity levels indoors are between 30 and 50 percent, but can often exceed that during the hot summer months, especially during a particularly rainy season.

Tips for reducing humidity indoors

High humidity can cause many problems in your home such as mold, mildew, dust mites, rust, wood swelling and doors sticking, in addition to creating a generally uncomfortable environment. A humid home can also cause health problems, such as allergies with itchy eyes, sneezing, nasal congestion, coughing and difficulty breathing, and may worsen asthma.

You can’t do anything to control the hot, humid North Carolina climate, but you can take several steps to reduce an overly humid indoor environment.

Here are some simple tips for reducing humidity in your home:

  • Make sure your home is airtight. Caulk any structural cracks or gaps and use weather stripping around doors and windows.
  • Cut down on those household tasks that produce water vapor. Take shorter showers and use cooler water. Cook using the microwave rather than the stove as much as possible. When boiling water, do not remove the lid.
  • Use energy-efficient ceiling fans to keep indoor air moving and keep the air drier.
  • Install exhaust vents in bathrooms and over the kitchen range.
  • Schedule an annual air conditioner tune-up with your HVAC contractor to perform maintenance that is crucial for the dehumidifying function of your AC.
  • Vent your clothes dryer outside.
  • Get rid of carpet, which holds in moisture.
  • Install a dehumidifier. A whole-house dehumidifier installed in the HVAC system can reduce humidity to a safe and comfortable level. Portable dehumidifiers are also quite effective, but have to be emptied daily.

How Do I Know My HVAC Technician is Well Trained?

What kind of training does an HVAC  technician need?How Do I Know My HVAC Technician

Every homeowner will at some time  have to hire a HVAC technician (usually through a Heating and Air Conditioning company) to maintain, repair, or replace his/her air conditioner or some of its components. To have peace of mind about the worker you are hiring and to ensure that your problem will be handled properly, it is helpful to know what kind of training and certifications air conditioning technicians are required to have.

There is no nationwide licensing requirement for HVAC technicians; the only federal requirement is by the US Environmental Protection Agency (EPA) which mandates that anyone working with equipment containing refrigerants must have EPA section 608 Certification. This is part of the Clean Air Act.  There are four types of EPA Certification, and the technician must pass a written exam specific to one (or more) of these specialties:

  • Type I – for technicians who will mainly be servicing small appliances/equipment
  • Type II – for technicians chiefly servicing high pressure appliances/equipment
  • Type III – for technicians who service low-pressure appliances/equipment
  • Universal – for technicians who service many types of equipment

There are many trade schools, employer associations, and community colleges with training programs to help prepare students for the EPA exam.

States differ on their requirements for the training and certification of HVAC technicians, and some states have no license requirement, but leave it to municipalities to set and enforce their own rules and regulations. In North Carolina, HVAC Contractors must be licensed, but for hvac technicians, the number and type of certifications required depend upon the type of work the technician will be doing.

A technician may begin his training by working in an apprenticeship program which includes on-the-job training along with classroom instruction, or he may opt for a more formal program such as those offered by technical or trade schools that are accredited by HVAC Excellence, the National Center for Construction Education and Research, or the Partnership for Air Conditioning, Heating, and Refrigeration. The technician could earn certification or an associate’s degree through these accredited programs.

The nations’s largest non-profit certification program for HVAC technicians is NATE (http://www.natex.org/). The motivation for its founding in 1997 was a concern (at that time) that many of those who were installing and servicing HVAC systems and equipment did not have the necessary knowledge and experience. The high standards set by NATE for the training and knowledge needed by a technician to obtain certification contributed greatly to the high level of skill and knowledge that HVAC technicians have today. There are an estimated 32,000 NATE-certified HVAC technicians delivering exceptional service throughout North America. NATE certification is not a one-time accomplishment. To ensure that certified technicians continue training and updating their knowledge as new developments take place in the industry, NATE certification must be renewed every two years (as of 2014).

Many  Heating and Air Conditioning companies, as a part of their hiring practices, offer paid training for those who want to become HVAC technicians. Many also offer or require continuing training to ensure that  their technicians maintain or upgrade their knowledge and skills.