[rx1rich]

I have an 1880's home 2600 sf and a new natural gas central heat unit bought 4 years ago. I have approx. 8 inches of blown insulation in the attic - my home is very old and somewhat drafty, but we just deal with it because we love it so! This year in October we noticed a spike in the gas bill, and it seemed to correspond to when we fired up the heater the first time. Long and short, the bill continues to rise. Normal usage the November and December bills is approx. 51 cubic feet - last month they say I went through 142. As of yesterday I was at 166, and the meter is not due to be read until January 7.

I keep the thermostat on 65 at night and 67 during the day, although I kept the daytime temp warmer in previous years. Heat and air men have been out 5 times and assure me everything looks fine - however, yesterday (29 degrees outside at 5 a.m.) I timed the cycle when I first got up and increased the heat from 65 to 67. At 2 hrs. 55 min. Of hard running by the heater, I decreased the heat to 66 degrees and let it shut down because frankly I was just nervous! (we had not yet reached 67 degrees inside at any point). I let it rest a few minutes, then adjusted the thermostat back up to 67. It fired right up, and thereafter the heater seemed to cycle normally. It's the initial push in the mornings that seems to be the problem.

It's not even cold in Arkansas yet and my gas bills are triple what they have been in the past 3 years when it has been really cold, with snow and ice on the ground. I have had a plumber check all the gas lines, no leak. The gas company has checked their lines, no problem. I KNOW with a 3 hour fire-up for 2 degrees increase that this is where my problem lies. I'm familiar with how this unit has run the past 4 years, and I'm familiar with my house. Something is wrong, but every technician points to the other person. I do not smell gas - not under the house, not in the attic, not in the house, and am assured if I had a gas leak of that magnitude I would surely smell it.

The heat and air guys agree something is wrong - 5 times out, and they have not found what the problem is. Whenever they are here everything works normally. When the guy was here yesterday it took about 20 minutes to go from 68 to 70, and we had 88 degree air blowing from the vents. Intake is fine. I asked if this was a staged heater thing, going from low to high but never actually hitting the high cycle - no, it's just a straight blow.

I'm ready to jump :-) I don't know what I'm doing, and the pros can't figure this out either. Anyone want to give me a hand? Nothing has changed since last year, or the year before - nothing other than a new hot water heater, but the plumber checked that too. And the increased bill started before the water heater was installed anyway. Everyone agrees there's a problem - now, what could it be?

[rx1rich]

Additional info - this is a Carrier 24ABR348A003 installed 3/17/2008. Unfortunately, I am unable to find any real manual information from Carrier? Because what I see says this is an AC - clearly, something is wrong...