Tip for reducing electric bills

[Fullboogie]

After six months of testing this and comparing bills, I can say that this worked beautifully:

In the first quarter of the year I went into my attic with the A/C set for full blast. I spent half a day tracking down leaks all over the place and sealing them. The worst offender on both units was the plenum box - massive leaks at the seams and where the ducting attaches. Second worst offender was where the ducts split into a "Y" and other connections. I fixed everything with new zip ties, top-notch tape, and sealing paste.

The last thing I did was pull the covers off the compressor units on the side of the house and clean the daylights out of the coils. After ten years they were disgustingly dirty. I just sprayed cleaner on them with a pressure pump, let it sit for a while, and then used high-pressure water to hose them off from the inside out.

After six months, my highest electric bill this year has been $201 for a 2,700 sq. ft. house at 9 cents per kilowatt hour. Last year at this time we were running in the $270 to $300 range. I don't know of any changes in our habits or usage. In fact, I'd say we have greater usage this year due to a second fridge in the garage, a thermostatically controlled vent fan in the garage, and a couple of new small appliances. I don't know if all of this reduction was due to the A/C fixes, but I suspect that to be the case. I looked over 4 years' worth of bills online, and this year has definitely been the cheapest, all else being equal.

In all, it appears to have been worth the small cash outlay and day's worth of work.

 

[RazorbackMustang]

Well done. I clean the outside unit once a year and it helps. Keeping filters changed regularly helps too.

Thanks for the tips about attic pieces though. I may look into that...

 

[Ampire]

One thing I've found is the more insulated and air tight the house the more the mold becomes a problem.

 

[Fullboogie]

Well done. I clean the outside unit once a year and it helps. Keeping filters changed regularly helps too.

Thanks for the tips about attic pieces though. I may look into that...

I think you'll be surprised at the number of very large leaks you'll find. Don't use standard duct tape to seal them up. Get some metal foil tape at Home Depot. There's also a sealant paste you should use over the tape, too.

One last tip - if you're doing this at a time of year when it's hot outside, don't sweat your balls off in the attic. After finding and marking all the leaks, disconnect one of the air tubes from the plenum box - it's nice and chilly!

 

[joeymustang]

I used to work in the HVAC industry and between 40-60% of bill comes from the a/c usage.

A programmable thermostat with occupied/unocuppied settings is also great. Also if the setpoint is lower than 72 each lower degree is about a 2% increase in energy usage.

 

[Dread53]

For 2700 ft that's pretty cheap! My stupid 800 sq ft apartment was regularly around $300 during the summer. Set back stat? I tried that for awhile with the crappy unit in the apartment, which also had west facing windows. I came home early one day (2 PM) and turned it from the daytime 76 to the evening 72. It finally shut off at 10 PM!

 

[mfergel]

One thing that really helped in my house was having an attic fan installed. Huge impact on my cooling bill during the summer months.

 

[VTXFrank]

One thing I've found is the more insulated and air tight the house the more the mold becomes a problem.

If you're having a mold issue, then your A/C isn't working right. A/C controls both humidity and temperature although, less of an impact on humidity. Sealing a house up so that it stays at a more stable temp would tend to lower your chances of getting mold. I'd be checking for leaks into the siding or the roof for rainwater. Otherwise, if you live in a humid environment, you'll need a stand-alone dehumidifier.

 

[06silverbullet]

my electric bill is 50 $ but we dont have ac, and use those cfl bulbs.

 

[Fullboogie]

So how does that contribute to this thread?

 

[stratman]

One thing that really helped in my house was having an attic fan installed. Huge impact on my cooling bill during the summer months.

What type of attic fan?A ceiling fan?

 

[mfergel]

What type of attic fan?A ceiling fan?

One of these. Guess it's called a Gable fan. Helps move the hot air out of the attic.

 

[kenneth]

I would kill for an electric bill in the $200 range, but I'm not going to sweat my ass off for it.
I keep the thermostat set at 68* running (2) 3 ton units, last 6 months bills average just under $400/ month.

 

[Fullboogie]

^^^I hear you man, it was not a fun day in the attic. But like I said, I disconnected a duct going to one of the rooms and was chilly all day. I'm willing to be you can drop those bills if you put some time into shoring up your system. Maybe wait until the end of the year when it's a little cooler...

 

[19COBRA93]

Or go up there in the night, or early morning before it really heats up. I need to do this to my system. I know it's not running efficiently. My bill has been higher this year compared with last, but over the winter I plumbed some vents into my garage so I have heat and a/c in there, and I think it's had an effect. I just left the vents open which has left my garage nice and chilly anytime I go in there, but my bill has been about $50 higher over the last couple months compared with last year. Regardless, that's a small price to pay for a nice cool garage to tinker on my car in, any time of the day.

 

[NastyStang113]

I had an AC from 1997 and replaced it this year with a Carrier. My electric bill was $400 and now it's $150, same month, and if anything we're using more power now. It's insane. I need to check the ducts though.

 

[Fullboogie]

Nasty, my AC units are nearly that old too, and I would love to buy some new ones. But the cost of replacing two units is just too much for me right now, which is why I did that work earlier this year.

 

[3vstang]

One thing that really helped in my house was having an attic fan installed. Huge impact on my cooling bill during the summer months.

^this x 100

Attic temps in the summer are drastically lowered.

 

[NastyStang113]

Well honestly expect them to go out soon. I'd say you're on your last leg with them. What mfg are they? My compressor went out and it was ridiculously expensive to the point where it was 2/3 the price of a whole new system, just didn't make any sense to not do it. Thankfully the unit went out during the winter and we were able to have 70 degree temps inside the house!

 

[isthatguy]

wow, my highest electric bill to date has been 120$ and my house is 3000k sqft. one story. slab foundation. with a 3 car garage. I keep the house at 80 degrees and have ceiling fans. im never warm in my house, and I live in South Alabama where its hot and humid as hell.