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jasv
Apr 18, 2005, 09:05 PM
My electric bill has been really high! Sometimes reaching over $600 for a 2400 sq ft house. I thought it was the cost of electricity and my family constantly using the central air conditioner. However last month due to some remodeling my central air system has been disconnected and my bill only went down about $75.

I was thinking I could troubleshoot this by measuring which cuircuits are using the most electricity. I know there are plugs that measure wattage used but I was hoping to start at the circuit level. What is the best way to figure out where the electricity is being sucked up? Would an "Amp meter" tell me? And if so, how do I measure it? I am handy enough and respect electricity enough to have installed a new service panel and some new circuits but I am not sure where to start here. And, yes, I know my "handiness" may have caused this.

caibuadday
Apr 18, 2005, 10:32 PM
My electric bill has been really high! Sometimes reaching over $600 for a 2400 sq ft house. I thought it was the cost of electricity and my family constantly using the central air conditioner. However last month due to some remodeling my central air system has been disconnected and my bill only went down about $75.

I was thinking I could troubleshoot this by measuring which cuircuits are using the most electricity. I know there are plugs that measure wattage used but I was hoping to start at the circuit level. What is the best way to figure out where the electricity is being sucked up? Would an "Amp meter" tell me? And if so, how do I measure it? I am handy enough and respect electricity enough to have installed a new service panel and some new circuits but I am not sure where to start here. And, yes, I know my "handiness" may have caused this. with the amp meter plus your ac thermostat (filter / usage time) u will able to tell how much electricity the central air system use

Flickit
Apr 19, 2005, 03:00 AM
My electric bill has been really high! Sometimes reaching over $600 for a 2400 sq ft house. I thought it was the cost of electricity and my family constantly using the central air conditioner. However last month due to some remodeling my central air system has been disconnected and my bill only went down about $75.

I was thinking I could troubleshoot this by measuring which cuircuits are using the most electricity. I know there are plugs that measure wattage used but I was hoping to start at the circuit level. What is the best way to figure out where the electricity is being sucked up? Would an "Amp meter" tell me? And if so, how do I measure it? I am handy enough and respect electricity enough to have installed a new service panel and some new circuits but I am not sure where to start here. And, yes, I know my "handiness" may have caused this.
Heater gas or electric? An electric hot water heater can be the culprit, especially if you have a number of people in your home showering on a daily basis.

jasv
Apr 19, 2005, 06:53 AM
About 2 months ago I replaced my electric water heater with Gas and still not much improvement in my bill. The central air is gas for heating.

Flickit
Apr 19, 2005, 07:16 AM
About 2 months ago I replaced my electric water heater with Gas and still not much improvement in my bill. The central air is gas for heating.
... watching your meter turn round and round (assuming you can see it), use it as a cheap way of finding the electrical 'leak'. Make certain your utility isn't in error due to their averaging practice.

labman
Apr 19, 2005, 07:19 AM
To measure power used, you need to know both amperage and time. Perhaps you could connect in hour meters to some of the suspected circuits. Most thermostats are not going to provide such information. Perhaps some of the programmable ones could. The hours used, plus the amperage, will tell you the power used, volts X amps X hours/1,000 = kilowatt hours.

Check with a more commercial electrical supply, there may be power meters meant to be wired in to circuits.

I can't think how an installation problem would cause excess power usage itself. There could be problems where you are heating and cooling the same space at the same time. You may not have enough insulation in some places. There is a ton of info on energy conservation out there. Go over it, and see what you find. How many TV's do you have, and how many are on being watched or not?

jasv
Apr 19, 2005, 01:24 PM
A key thing I want to point out is that my AC/Heater has been completely disconnected for the last month but my bills are still sky high.

A question: Can a short or a hot connected to a neutral cause my usage to be higher?

I do have 15 computers, 5 TIVos, and 6 TV's. Saying that makes me wonder if maybe I am getting a deal at $600/month.

labman
Apr 19, 2005, 02:39 PM
Any sort of a short that drew any power would convert the power to heat. Something would be getting very hot. Most of the conventional CRT monitors go into a sleep mode soon if no input from the keyboard or mouse. However sometimes my dogs manage to shake the desk enough to wake the monitor up. I would look at the TV's I don't think TVIO's draw much power, but large CRT's do. You might pressure the family to turn stuff off they aren't using.

Flickit's idea of watching the meter may help too. Read it by taking the lower number where the hand is between 2, if one hand is almost to 4, and the next between 8 and 9, read it as 38. Compare your readings with the electric companies. Utility companies have little faith in customers being able to read meters. Many years ago, one of our neighbors added gas service. All summer the gas company was billing them for the gas our hot water and dryer used.

tkrussell
Apr 19, 2005, 06:07 PM
A 2400sf house, with 15 PC and 6 TV's, AC, and electric hot water recently changed to gas makes me wonder what else you may have in the house, and how many people are using the lighting and appliances.


Electric range(s), dryer, clothes washer, refrigerators, freezers, dishwasher with dry cycle ( uses an electric heat element simlilar to a range), interior lighting, large quantity of exterior lighting, any power tools such as air compressors, pool pumps, pool heaters, spas/hot tubs (with electric heaters to keep the water hot constantly).

Is the HVAC a heat pump system? These systems use the AC compressor in the cold periods to extract heat from outside air, and use electric heaters to supplement the prime heat.

Some quick theoretical calculations to show that if you have some or many of the items I mention:
30 day month has 720 hours.

If you use an average of only 25 amps each hour at 240 volts for all 720 hours at an average of ten cents per Kilowatt-hour totals $432.00, for electric consumption alone, plus fees, taxes, utility service charges, sure adds up quick.

Ask the utility to help explain how your bill is calculated. You may discover that you are penalized for using more energy during certain times of a day, called peak usage hours. Then look at all the appliance you may have, plus how many are used during what time of the day, and how many lights etc. are left on when not necessary.

There are many factors as to the reason for large electric bills, including faulty electric meters. Ask the uitilty to test your meter for accuracy when you call for help to understand your bill.

Short circuits will not add anything to your consumption, because the circuit breakers will detect the short and open, or trip.

Not sure if this helps to find the exact problem, but I hope this gives you plenty to check into and think about

jasv
Apr 20, 2005, 01:15 PM
Tkrussel,
Thanks for your reply it helps a lot. I just need to take a systematic approach but I am starting to think I don't have a big problem.

hrhotrod
Sep 30, 2007, 07:03 PM
I have the same problem:

1
1672 WHR this August, 1654 last August.

2
Measured my two PCs, cable box, projector, water bed heater two refrigerators, etc with a Kill-a-Watt meter and did a power addup.

3
Inferred pool pump at 80% efficiency on the 3/4HP rating, and inferred 107KWH for the month (5hr/day)

4
Estimated 20 light bulbs at 75 watts for average of 4 hours per day for 183KWH for the month.

5
Haven't figured out A/C yet.

6
Can get to only 65% of the 1600KWH.

7
Something sounds wrong! Please comment, please... What could be wrong? I can't think of what else could be dissipating 40% of the KWH on my bill.

HR

tkrussell
Oct 1, 2007, 05:44 AM
Focus on the AC.

For example, an AC unit drawing 15 amps at 240 volts will be 3600 watts, and at 8 hours per day, 30 days a month, will equal 864 KWH.

Shows that AC can be a heavy kicker.

What type of water heater?

Plus all the little things, like clocks, power supplies, battery charger for phones, etc. smoke detectors, All very small but add up.

hrhotrod
Oct 1, 2007, 09:52 PM
Tk, thanks.

I just found out today what the dissipation of my allegiance 15 a/c is, and you are right.

Also, you are right that the little things add up.

I'm now in the mid 90s% on om addup, with a reasonable fitting parameter of days/month on on the A/C.

HR

Stratmando
Oct 2, 2007, 06:15 AM
As far as an Amprobe, If you are comfortable with electricity, Remove panel cover,
Clamp around each wire coming off each breaker, and measure current off each,
Look for anything unusual. Also a quick test would be measure current of both mains individually, then measure neutral. The neutral current should be the difference of the two
Main feeds. If not, something likely going to ground. Place amprobe around grounds in panel also, none should be carrying current.
Keep in mind some items may not be at maximum load(compressor not on, on frige, etc