John C. Semmelhack
  • Charlottesville, VA
  • United States
Share on Facebook Share on Facebook Share Twitter
  • Featured Blogs
  • Discussions (8)
  • Events
  • Groups
  • Photos
  • Photo Albums
  • Videos

John C. Semmelhack's Friends

  • Roch Naleway
 

John C. Semmelhack's Page

Latest Activity

John C. Semmelhack replied to George Kopf's discussion How does efficiency factor into a grid parity world?
"Graham, The U.S. is catching up to Germany very quickly on solar installs. As of the end of 2013, the Germany-to-U.S. cumulative installed solar capacity ratio was about 2.6 to 1. At the end of 2014, it will be closer to 2 to 1. The U.S. will likely…"
Oct 23
John C. Semmelhack replied to Jack Baikoff's discussion Measuring fresh air intake ducted to a return and no way of measuring from outside.
"HVAC contractor (ideally) drills the 1" hole, then tapes over afterward.  I invested about $250 for 4", 5", 6", 7" and 8" versions of the device. "
Jan 24, 2013
John C. Semmelhack replied to Jack Baikoff's discussion Measuring fresh air intake ducted to a return and no way of measuring from outside.
"By the way...not sure what climate you're in, but someone should probably should insulate that fresh air duct!"
Jan 24, 2013
John C. Semmelhack replied to Jack Baikoff's discussion Measuring fresh air intake ducted to a return and no way of measuring from outside.
"There are in-duct measurement techniques that are accurate enough for this purpose. Here's what I use - http://www.kele.com/flow/fxp-series.aspx It's essentially an "averaging" pitot tube to take care of the likely…"
Jan 24, 2013
John C. Semmelhack replied to Jack Baikoff's discussion Measuring fresh air intake ducted to a return and no way of measuring from outside.
"Why are you wondering how much airflow occurs at this intake?   1) Required for Energy Star 3.0 certification 2) Code compliance 3) Ensure there's enough airflow to help ensure healthy indoor air quality 4) Ensure there's not too…"
Jan 24, 2013
John C. Semmelhack replied to Curt Kinder's discussion AirGenerate Heat Pump Water Heaters - any experience?
"Dan,  Good to hear you're evaluating the reduced airflow form the CAR's. I'm interested to see the results.  Regarding the discharge airflow - comfort issues are relatively easy to mitigate with location, placement and…"
Nov 20, 2012
John C. Semmelhack replied to Curt Kinder's discussion AirGenerate Heat Pump Water Heaters - any experience?
"Dan,  Have you measured the drop in efficiency/capacity caused by reducing the airflow?  Why are you recommending exhausting the discharge outside of the house?  John "
Nov 16, 2012
John C. Semmelhack commented on Roch Naleway's blog post Borrowing from solar thermal system - Why not use two tank systems with heat pump water heaters?
"Are you kidding me? That's the worst thing I've heard all month. Cutting the airflow across the heat exchanger of a heat pump system by 50-60% will significantly reduce capacity and efficiency. I'm glad I'm not a rate-payer in…"
Sep 13, 2012
John C. Semmelhack commented on Roch Naleway's blog post Borrowing from solar thermal system - Why not use two tank systems with heat pump water heaters?
"The ATI-50 and ATI-66 have a 6" diameter discharge collar on the top of the unit that can be ducted in the case of installations in small spaces. In the particular scenario I've been discussing, the discharge is ducted about 15' over…"
Sep 13, 2012
John C. Semmelhack commented on Roch Naleway's blog post Borrowing from solar thermal system - Why not use two tank systems with heat pump water heaters?
"The ATI-66 for the seven-person household is in conditioned space (hallway closet between kitchen and living room), so the ambient temperature is pretty consistent. I'm sure HPWH's have a harder time keeping up with demand in colder months…"
Sep 13, 2012
John C. Semmelhack commented on Roch Naleway's blog post Borrowing from solar thermal system - Why not use two tank systems with heat pump water heaters?
"It seems like a better solution would be a larger tank for the HPWH in these situations, such as the Steibel Eltron or the AirTap ATI-66. Certainly, both of these are more expensive than the 50-gallon models from GE, Rheem etc., but they also have…"
Sep 13, 2012
John C. Semmelhack replied to Pam Worner's discussion DHPs in MF projects
"Yes, this can be done and is done.   Many of the ductless heat pump manufacturers have these types of units available. The most well-known is 'City-Multi" from Mitsubishi. The ratio of indoor units to outdoor units depends on the…"
Nov 10, 2011
John C. Semmelhack is now a member of Home Energy Pros
Oct 11, 2011

Profile Information

Company
Think Little
Professional Certification
Certified Passive House Consultant, HERS Rater, EarthCraft Virginia Technical Advisor, BPI Building Analyst
Website URL
http://www.think-little.com
Blog URL
http://www.think-little.com

Comment Wall (1 comment)

You need to be a member of Home Energy Pros to add comments!

Join Home Energy Pros

At 1:19pm on October 11, 2011, Diane Chojnowski said…

Hi John,

Welcome to Home Energy Pros! Feel free to join the conversation in the Forum and Groups. And share your energy efficiency photos, videos and upcoming events. If you're blogging about home performance, this is the place for you!

Don't forget to upload your profile photo. And add your location on our Member Map!


Thanks!
Diane, HEP Moderator

 
 
 

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.

Latest Activity

Colin Genge replied to billy g pinnick jr's discussion Blower Door Question
"I didn't take your comment as a challenge. I agree that his impression of what was occuring is…"
3 hours ago
Tom White posted a blog post

Clean Energy Works Oregon: Total Home Performance

Clean Energy Works Oregon (CEWO) is the largest nonprofit home performance provider in Oregon,…See More
6 hours ago
Tom White posted a video

Twas The Night Before a Clean Energy Christmas

From the foothills of the Rockies, RMI editorial director Pete Bronski reads 'Twas The Night Before a Clean Energy Christmas. Happy Holidays and Happy New Year!
6 hours ago
Chad Mcaulife commented on Green Jobs Training Center's photo
6 hours ago
Chie Kawahara's discussion was featured

THC Candidate Shares Energy Data

Midori Haus, a Passive House retrofit in Santa Cruz California and a Thousand Home Challenge…See More
6 hours ago
Bob Blanchette's discussion was featured

How does Cycles Per Hour affect real world AFUE?

Some claim that modern furnaces have minimized off cycle losses to the point they no longer matter.…See More
6 hours ago
Dale Stephens's blog post was featured

LED Lighting 24-month update 18,240 hours & counting

Background:In November 2012 I replaced 80% of my home's interior lighting with LEDs (35 bulbs…See More
6 hours ago
Home Energy Magazine's blog post was featured
6 hours ago

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service