Monthly Archives: December 2016

Blower Door Home Energy Audit

Energy Efficiency, , ,

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!

8 Gas Appliance Safety Tips You Can’t Afford to Ignore

Household, , ,

Gas appliances are not inherently dangerous. In fact, they’re exceedingly safe, as long as they’re well-maintained and treated with care and respect.

YOU CAN’T AFFORD TO IGNORE

If you have a gas-fueled furnace, room heater, stove, or water heater in your home, here are eight safety tips you would be wise to follow:

  1. Install carbon monoxide detectors in the immediate vicinity of each appliance.

If you have gas-burning appliances in your home, carbon monoxide poisoning is the biggest risk you face. Every year, thousands of people are sickened by exposure to carbon monoxide, and a few people pay the ultimate price.

Carbon monoxide detectors are highly sensitive, and they’ve saved many lives. They do need to be installed fairly near gas appliances to work correctly, and you should change the batteries twice a year even if the low-battery warning beeper doesn’t sound.

  1. Learn to recognize the signs of carbon monoxide poisoning.

Carbon monoxide detectors are great, but carbon monoxide is so dangerous that you shouldn’t count on them exclusively. Even if they do go off during a leak and you manage to flee, someone may be exposed to hazardous levels of carbon monoxide before you can get out of the house.

The telltale indicators of carbon monoxide exposure include these:

  • Dizziness or vertigo
  • Steadily increasing drowsiness
  • Tension headaches
  • Muscle and joint stiffness
  • Blurred vision
  • Disorientation, confusion
  • Nausea, vomiting
  • Loss of consciousness

If you or anyone else in your home experiences any of these symptoms, leave the house, open all windows and doors on the way out, turn the gas off at its source, and call the gas company (after you exit the house) to alert them to the danger. If anyone’s illness persists, or if anyone loses consciousness, call 911 and ask them to dispatch an ambulance immediately.

  1. Keep the floor and wall space around your gas appliances free and clear.

Don’t install gas appliances near cabinets or shelves or in a spot with a low ceiling. Don’t push the appliance right up against the wall, and keep the floor space around it clear of all obstacles for a distance of 4-6 feet.

  1. Don’t store combustibles anywhere close to a gas-burning appliance.

If it burns, you should keep it far, far away from your gas furnace, heater, or stove. In fact the best idea is to store your chemical products, oil or kerosene cans, paint, newspapers, magazines, and any other flammable items in an entirely separate location.

  1. Make your gas appliances off-limits to children and pets.

No matter how responsible and careful your kids (or cats and dogs) might be, why take any chances?

  1. Check your gas appliance vents often to make sure they remain clean and open.

Vent maintenance is fairly simple and straightforward. Fortunately, modern gas appliances are often manufactured to shut down if venting is inadequate, but if you inspect the vents yourself and clean them out as needed, you’ll have nothing to worry about.

  1. Look for soot accumulation, a yellow pilot light flame, or any other sign of damage or diminished performance.

Older gas appliances need extra-special attention. It might be a good idea to get rid of your furnace, heater, or stove before it ages too much, but at the very least, you have to watch it carefully for any signs of breakdown or malfunction.

  1. Arrange for regular maintenance visits from an HVAC contractor (and other professionals if needed).

If you have a gas furnace, this is where Johns Plumbing, Heating, and Air Conditioning can really help you out. Call us to make an appointment before heating season begins, and we’ll send a trained technician to your home to inspect your furnace for any sign of damage. Quick tune-ups are free, and if more extensive repairs are needed, you’ll be happy to know we’re one of the most affordable contractors in the area, and our technicians are highly experienced in all types of repair procedures. We can also give you the chance to enroll in our maintenance program, which will ensure regular inspections as well as saving you money on parts and labor.

Keeping your gas appliances in tip-top working order at all times is one of the best ways to ensure their continued safe operation, and no matter what type of gas appliance you own, it’s always good to have the assistance of a professional.