Attention Wrightsoft Users!

  Have you ever completed a load calculation and it just seems like it was short of what you had expected?  Particularly when you are first starting out with a tool, contractors can make mistakes. After all, we tend to learn "the hard way", right?  In an effort to make software work, the companies tend to start with some default values that require adjustment.  For instance, most have the duct system in the conditioned space calculating zero gains or losses.  If the ducts were in the attic, this could be as much as a one ton load that is missed! Internal gains tend to start at zero, and the foreground for windows is something between crushed rock and green grass.  Most contractors find these values, over time and as they gain experience with the program.  One still overlooked setting in Wrightsoft, a feature that no other ACCA approved software employs, is the Rate Swing Multiplier (RSM).  This can cause you to lose as much as 11% of your sensible gains in an otherwise perfect load calculation, maybe more!

Read More

Views: 176

Replies to This Discussion

YES running loads is like rounding up kats.  You very big knobs like south windows, open return in attics, unsealed supply's of building,   I was at a new home 2 yr old  this week - she claims the 1560 sf 4 spit  75,000 BTU/hr 2.5 ton AC is not big to H/C home.  So I just ran a load and come up with 2/3 of that  but when I ran the blower door  a big -50 PA was 3020 CFM  this home did not get sealed between walls where the plumbing comes up.  The HVAC sheet steel installer got the wrap but I feel the low end builder got what he paid for.   Then HVAC contractor  just put in  a 3 ton and 100,000 BTU and now will bid just this over sized "system".

My point is You must test out.     I have used  Wrightsoft for 20+ yr  and I feel it over sizes 10-25% If you do not test out and redo the numbers.   One of my .goals is to beat the 1st load.   To test is find run time when the temp outside is at design temp - I look for 100%  run time with out the heater hitting high limit.    Gramps told me to size to -40  and I use now 0'.    Now you see that  systems get over sized 

RSS

Videos

  • Add Videos
  • View All

Twitter

Latest Activity

Rob Madden, Solar Home Broker replied to Rob Madden, Solar Home Broker's discussion Indoor Air Quality Monitors and Meters
"Awesome respnose...thanks for your insight!"
10 hours ago
Zane Goff replied to Rob Madden, Solar Home Broker's discussion Indoor Air Quality Monitors and Meters
"We use the air advice quick test device and I'd recommend it for the depth of home…"
12 hours ago
Amber Vignieri posted a status
"#Solar does WHAT?! #SunShot busts myths aboutt #SolarRealEstate http://energy.gov/eere/articles/5-common-myths-about-residential-solar"
12 hours ago
Profile Iconnaryking, Rob Hoehn, Hannah Wood and 2 more joined Home Energy Pros
15 hours ago
Chris Laumer-Giddens posted a blog post

Building with Rocks, Rocks. Check out the Drying Potential

Building with Rocks, Rocks! Check out the Drying Potential.Check this out! This 24" x 48" x 2"…See More
18 hours ago
Evan Mills's blog post was featured

Looking Back and Looking Forward: Home Energy Pros at 5 and 5000

Over the past five years, the Home Energy Pros social network has grown from a twinkle in our eyes…See More
yesterday
Eve Dunham joined Diane Chojnowski's group
Thumbnail

News & Announcements

Share your news and announcements with the community in this group.To post news or an announcement,…See More
yesterday
Eve Dunham joined Tom White's group
Thumbnail

Weatherization

Share your concerns and successes as a weatherization professional, or information for this…See More
yesterday

© 2016   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service