Christopher Morin's Blog – June 2012 Archive (3)

Ever since the adoption of the 2009 International Residential Energy Conservation Code (IECC), duct sealing efforts have been tested using the total leakage or leakage to outdoors methods.  It really is amazing how much duct gains effect the operation of your equipment and the comfort of your customer.  The missing part of "duct testing" appears to be how well the ducts are insulated.  Sure, you are required to use R-8 insulation on supply ductwork when located outside the building envelope,…

  When completing your site survey for Manual J Load Calculations, significant time can (or should) be spent identifying window values.  Did you know that most windows these days come with an NFRC rating, a tag located in the window jam that you can reference on NFRC.org? This identification number can tell you important details like window coatings, u-value, light transmittance, air leakage, and solar heat gain coefficients (SHGC).  Not identifying the correct values can sway your load…

How do you know if  should upgrade your air-conditioner to a heat-pump and create a dual-source application during replacement this Summer?  I personally always prefer the option of multiple fuel sources, particularly since energy prices have been all over the place during the last decade.  Fortunately, based on average energy prices, there is some simple math to figure out if an aggressive assessment should be made for a dual-source heat pump application, based on equations from ACCA's…