Does locating an AC condenser out of the sun (east vs. west side of house) make significant difference in real world efficiency? Does anybody have a link to a case study?

Views: 220

Reply to This

Replies to This Discussion

Hello Bob,

This topic has been thoroughly researched, indeed:  Condensor Shading . They conclude that any savings produced by localized HVAC condenser shading are modest, <3%, or even less. Much more important is the effect of vertical and horizontal air blockage. I have currently been recommending to my clients the following: zero vertical impedement for 20 feet, two feet from house, two feet from fences or bushes, five feet from any other condensors. I hope this information is helpful to you!

Tom Delconte

Hi Bob,

I was given a report a handful of years ago by our coating distributor in Texas.   He gave me the following information.

His neighbor had an ac unit with the condenser on the outside at ground level.  Two pipes ran up the wall to attic floor level, made a 90 into the attic.  For years the neighbor left the pipes bare, bare metal.  H e at some point had wrapped them with foam pipe insulation.  He had noticed no improvement in the air temperature or his electric bill.

 

Our guy. Joe Merrill, suggested they remove the foam and coat the pipes with our  radiant barrier coating and see what happens.  They did that and the owner said he and his wife felt it made a difference in the temperature of the house.  They were happy and it was left like that.

No exact temperature readings were taken and I never heard if there was any noticeable difference in the electric bill.  I wish I could find out more particulars but Joe passed away in early 2013.

 

An effective radiant barrier material provides a shading effect.  Any time yuou can provide shade or a shading effect on outside cooling equipment, absolutely it is going to alloow that equipment to operate more efficiently.

 

One must also be aware that EVERYTHING around a building absorbs the sun's radiation during daylight hours.  Those 'things' then radiate that heat out towards the cooling equipment that it must overcome, even in the shade of a house, tree, etc.  AND those things will still radiate heat in all directions after the sun goes down.

I recall a large hospital in Porterville, CA.  On one of their 3 levels of roof, you could hardly see the roof because of the ductwork on top.  They had spent a fortune with a machine shop that mader, basically, oversize galvanized shrouds that were set over the top of the existing galvavized ductwork.  They did this to provide the 'Shading effect' they hoped would drop their electric bill and cool all their labs below.  It had next to zero effect as the metal shroud got to 196 degrees and radiated that heat inwards to the galvanized ducts.  They had no clue about heat transfer.  Ther was a 4 inch distance between the shoud and the duct metal.  They still experienced heat gain from radiation and convection.

 

In the hot months, ANYTHING you can do to provide shade will help.

 

 

 

 

 

I'm with you on the small local shading as shown in the study, don't think it makes much difference. Moving the condenser from the sunny to shaded side of the building *may* be different due to the potentially cooler air entering the condenser. Outdoor temp sensors for weather stations show a higher temp on the sunny side of the building even when the sensor is shaded.

RSS

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

Tom Conlon's discussion was featured

Whole House Fans - Love 'Em or Not?

I just searched this forum for "Whole House Fan", but I didn't find much about them (except …See More
22 minutes ago
Tom White shared Brandon Walton's blog post on Twitter
25 minutes ago
Brandon Walton's blog post was featured

12 Things Every Home Performance Contractor Should Have on Their Work Truck

Every home is unique and differs from the last. It would be a perfect world (from a project…See More
26 minutes ago
Griffin Hagle replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
1 hour ago
Griffin Hagle replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"Kurt, Whoops, looks like I got my links mixed up. Thanks for pointing that out. Here's the…"
2 hours ago
Kurt Shafer replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"Glen,  I went to Homepower.com and did a search for whole house fan. Could not find that…"
2 hours ago
Glen Gallo replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"I no longer have my subscription to the Home Power Magazine but these figures were pulled from the…"
2 hours ago
Kurt Shafer replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"Glen,  I read your blog with some interest.  You say  " Per the Home…"
3 hours ago
tedkidd commented on Scott Mellberg's blog post Lessons from Energy Efficiency Advisors: Getting Homeowners Onboard with Home Performance
"OMG, you are one of those myopic thinkers are you? Others do it better therefore drastic action is…"
3 hours ago
Glen Gallo replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"I do not like them and I am in Southern California. I think the whole house fan in prescriptive…"
3 hours ago
Kurt Shafer replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"Griffin,  Is this really the link you…"
4 hours ago
Kurt Shafer replied to Tom Conlon's discussion Whole House Fans - Love 'Em or Not?
"Tom, great new post! Thank you for the focus. As you know, the term "whole house fan" is…"
4 hours ago

© 2014   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service