Green Building

Pinless Moisture Meters

Subtitle:  How to use them — and how not to use them Images: 

I got a call the other day from a builder client, who said, “Hey Peter, a new homeowner of mine is super-worried about moisture and mold and is getting scary readings with his pinless moisture meter. Help!”

Pinless moisture meters read from the surface of any material, using an electromagnetic field. Feedback from this field provides information to estimate moisture content. These meters are called “capacitance-based” meters, while pin-type moisture meters are called “resistance-based” meters.

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The Important Stuff You Need to Know About Ceiling Fans

Prime:  prime Subtitle:  Here are a few basic principles that many people don’t understand Images: 

Here we are in the middle of air conditioning season.  So why don't we chop down some myths and misconceptions about ceiling fans?

What got me on to this topic was a video of a fan with blades that hide on top of the fan when the fan is turned off. Sounds clever, but it's a ridiculous idea.

Anyway, here are seven things about ceiling fans that a lot of people seem not to know.

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An Update on the Residential Ventilation Debate

Prime:  prime Subtitle:  Here’s what you missed at the ASHRAE 62.2 committee meeting last week Images: 

It's been a while since I've written about what I had been calling "The Great Ventilation Debate" back when Joe Lstiburek was battling the ASHRAE 62.2A standard for residential mechanical ventilation systems established by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers. Among other requirements, the standard requires a home to have a mechanical ventilation system capable of ventilating at a rate of 1 cfm for every 100 square feet of occupiable space plus 7.5 cfm per occupant. residential ventilation committee. The 62.2 committee meets in person twice a year at the two ASHRAEAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). International organization dedicated to the advancement of heating, ventilation, air conditioning, and refrigeration through research, standards writing, publishing, and continuing education. Membership is open to anyone in the HVAC&R field; the organization has about 50,000 members. conferences, and they just met last Friday and Saturday in Houston, Texas.

A few things have happened over the past few years, so let me give you a brief update.

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Do Solar Panels Need to be Cleaned?

Subtitle:  How the accumulation of dust, pollen, and bird droppings affects the energy production of a PV array Images: 

I was at my brother’s house in Lee, New Hampshire, recently and looked up to see that his photovoltaic(PV) Generation of electricity directly from sunlight. A photovoltaic cell has no moving parts; electrons are energized by sunlight and result in current flow. (PVPhotovoltaics. Generation of electricity directly from sunlight. A photovoltaic (PV) cell has no moving parts; electrons are energized by sunlight and result in current flow.) panels looked a bit dull (see Image #2 below). His PV array is easy to get to — the long north slope of his roof has a walkable 5:12 pitch — so we went up and took a closer look.

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Simple Steps to Improve Air Conditioner Performance

Prime:  prime Subtitle:  If your air conditioner struggles to keep up in the heat, these measures can help Images: 

It's getting hot out there. Here in the Southeast, we love our air conditioning.  In fact, without air conditioning, far fewer people would live in places like Houston, Hattiesburg, and Sopchoppy. And that's true for the hot, dry places, too, like Phoenix, El Paso, and Boron.

So if we're going to have air conditioning in our homes, we want it to work.  It should be effective and efficient.  It should keep us cool without creating new problems, such as excessive noise, bad indoor air quality, or comfort that varies from room to room.

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How to Read Manual J Reports

Prime:  prime Subtitle:  If you know what to look for, it’s easy to check for accuracy Images: 

When you enter the world of building science — whether through building a house, becoming a home energy rater/building analyst, or just hanging out in cyberplaces like this — everyone talks about the importance of getting actual heating and cooling load calculations based on ACCA Manual J. A great number of HVAC(Heating, ventilation, and air conditioning). Collectively, the mechanical systems that heat, ventilate, and cool a building. contractors sell and install oversized equipment with air distribution systems that don't work because these contractors base their choices on rules of thumb.

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Proper Sizing Isn’t the Real Reason for HVAC Design

Prime:  prime Subtitle:  Yes, size matters, but another factor matters more Images: 

Many people seem to think HVAC(Heating, ventilation, and air conditioning). Collectively, the mechanical systems that heat, ventilate, and cool a building. design means you get a load calculation (Manual J in the ACCA protocols) so you know what size system to put in. Hey, that's a great start. It's way better than just using a rule of thumb or Manual E (for eyeball).

But there's so much more to real HVAC design than simply finding out how much heating and cooling a building needs when it's at design conditions. And we might as well start with the fact that my first statement is incorrect: The load calculation does not tell you what size system you need.

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Understanding and Measuring Mean Radiant Temperature

Subtitle:  Mean radiant temperature, a major component of thermal comfort, is easy to measure Images: 

All the way back in 1993, one of my first research projects at the NAHBNational Association of Home Builders, which awards a Model Green Home Certification. Research Center was assessing the performance of radiant ceiling panels for the Department of Energy’s Advanced Housing Technology Program. (The final report was titled “An Evaluation of Thermal Comfort and Energy Consumption for the Enerjoy Radiant Panel Heating System.”)

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