View Full Version : Moving A/C supply vents - cost savings?



SoonerDave
07-20-2012, 09:56 AM
I have a very frustrating situation that needs to be remedied, but I'm not quite sure how to go about it.

Simple version: My home's A/C supply vents are located incorrectly. I should have noticed this when I built the house, but all I can admit to is being stupid about it. The vents are *all* in the middle of their respective rooms - not ONE vent is near a window. For two bedrooms, the supply vent is within three to five feet of the return air duct, and some very unscientific tests I've conducted show me I'm sucking up nice, paid-for cold air that does my house zero good. Two different A/C folks were stunned at how my vents are laid out. One guy said, "This is, well, kinda odd..." and he was trying very hard not to be insulting to me.

Bottom line - I need to move about seven vents, maybe even add one or two - to areas near an exterior walls/window. I've talked to one company who said they won't do a job like that in the heat of the summer, but might be willing in September, for about $1K, which he said boiled down to a "time and materials effort." Both companies I spoke to said my vents were set up as they were because the HVAC vendor my builder used was going the cheap and quick route, and looking in my attic its clear that's exactly what they did - main supply line down the middle of the house, with short branches to the supply vents in each room. Crappy work.

Now, the problem is this: I know I'm wasting kWh and $$$, but I don't know how to assess/model/guesstimate how much I'm wasting because of these misplaced vents. In reality, rather than cooling the air at the source of the greatest heat gain into the room, I'm effectively trying to cool ALL the air in the house, and that's racking up big-time kWh consumption. I don't mind spending $1K to move the vents, but I'd sure like to get *some* idea of how long the payback is going to be. I fear that the "excess" electrical consumption is something on the order of several hundred kWh per month, but that's speculative.

I know I could (maybe?) save a few bucks on a lower rate plan, but I'd rather reduce my actual consumption. I sure could use some suggestions or help on how much moving these vents will really save me.

Thanks,
David

Skyline
07-20-2012, 12:46 PM
You may start here:
http://www.oge.com/residential-customers/save-energy-and-money/EnergyEfficiency/Pages/HomeEnergyEfficiencyProgram.aspx/

SoonerDave
07-20-2012, 01:20 PM
You may start here:
http://www.oge.com/residential-customers/save-energy-and-money/EnergyEfficiency/Pages/HomeEnergyEfficiencyProgram.aspx/

Thanks, but what I've read/understood about that plan is mostly a top-level review of managing thermostats, benefits of insulation, turning off lights, switching to a gas water heater (already have one), etc., very generic power conservation stuff. I think I need something a bit more specific. Now, if OGE wanted to help pay for moving the air vents... :D

WilliamTell
07-23-2012, 04:43 PM
I'm not sure if you have kids or other requirements but in my earlier years (before kids, etc) my wife and i made use of a window ac unit to cool the bedroom during the summer instead of the central air on the rent house(s) we used to live in that varied from 15-60 years old - and even 1 summer in our newer house. The house a/c was on while we were home and about an 20 minutes before bed we would turn on the bedroom a/c. Really when you think about it its pretty wasteful to cool all the sqftage in your house when youre in one bedroom from 9pm - 7am. Two cents.

Anymore a lot of the little window a/c's are pretty powerful and good on energy esp if you have an older house.

boscorama
07-23-2012, 09:14 PM
Window units rock!

SoonerDave
07-23-2012, 10:07 PM
My house isn't exactly new, but its not vintage, either. I built it in 1999 (well, contracted it to be built then). Not quite ready to give up on the central A/C just yet, but who knows --- never say never.

BTW, did contact OGE about their audit program, and as I feared, they don't do any detail work. Top-level, "weatherstrip your doors and change your air filters" stuff, and they charge you $50 for it. No thermal imaging, no blower door tests, nothing of substance you need to do the kind of analysis I suspect I need.

stick47
07-24-2012, 05:37 AM
Seriously considered a multi zone split mini system when our home was built. Cost would have been comparable to a high efficiency heat pump but we went with the 15 seer heat pump since resale value down the road was a factor. I did install a mini split in my man cave. it's a 12K BTU, 20 seer. Upsides besides the low energy costs are how quiet it is and that it could be placed on the wall away from the window. It was able to make good heat even when the temps were in the low 20s. The other energy saver in our home is the GE heat pump water heater. It consumes less than half the energy of a standard electric water heater. (> $200/yr vs < $500/yr)