Thanks for the reply.  Bombard away with questions as I appreciate any information.  I really believe in this technology, believe my installer to be experienced as much as we could assess, and believe that there's likely something fixable here. 

The assumptions weren't made on a single week, as I've also been tracking the CDD's and the usage daily for the first two weeks of this heating cycle, too.  We're located outside Austin, Texas, and that's one thing I wanted to ask.  We were in drought when the ground loop was laid and it has not rained since.  As I type this, we are setting sprinklers up over part of the loop field in the hopes that the drought just kept the loops from ever making good contact with the ground.  It's going to take a while and an awfully guilty use of water in our drought-stricken area to water 1500 feet of loop field, though. 

The SEER and tonnage of the old system were 13 SEER and 5 ton.  The new system is rated at EER 27 and 3 tons, which our installer insisted was enough.  We're not having any difficulties cooling the house, just paying more for it than we were before.  We have approximately 1500 feet of horizontal loop.

Careful load calculations appear to have been done.  We have material from our installer, one who has done around 250 geothermal systems in this part of Texas. Austin is a hot spot for green energy methods.  He appears to have used WrightSoft, calculating window by window, door by door, etc., and using ClimateMaster's GeoDesigner. 

Our monthly kilowatt usage changes of course, with the season, but had been dropping as we replace, room by room, incandescent lights with LED or CFL's, employ the use of a Sun Oven, etc.  Our usage had been tracking steadily lower, but ranged between 1500 down to 1000 over the last few months.  We're on track to exceed 2100 this month, however, higher than we've ever had other than one winter month.  

Yes, I can read our meter several times a day.  I began recording numbers two days ago when we received our electric bill.  

All of our ductwork is in the attic and has always been.  It's of course blazing in an attic with 100-degree weather here, but that's true of any Texas summer, although this one is hotter than normal.  But it was hotter than normal a month ago, and as I noted, the CDD's had actually gone down over the billed period.  Yes, the ductwork is insulated and sealed, and is essentially as it was before the install.  Yes, the old system's air handler was in the attic, too, with the old system's compressor outside, on the west side of the house.

There has been no change in electrical usage, with the only change being that we replaced incandescent lights with LED lights in two more rooms this last month, including my office and the master bedroom.  That should be decreasing, not increasing costs.  There has been no change in work habits or computer setups since the install or in my habits in turning it off when not in use.

You asked about the entering water temperature.  I don't know how to measure it but I just did a put-my-hand-on-the-pipe test and, honestly, that entering pipe doesn't feel a whole lot cooler (insulated, in the garage) than the exiting one.  I could take a warm bath in that water.  I would love information on how to measure it, but then what do we do about it if it's too hot, as I now suspect it is?  Is this fixable without digging up the whole field which ranges across a good portion of our one-acre lot?

Thanks again for all the information and suggestions. 

I'd hate to label our system a problem system:  I like our installer too much (so far) to do that, but it's not serving our primary purpose just yet, it appears.  Because our primary purpose was to lower monthly usage with a view that would make the eventual purchase of a grid-tied PV system less expensive, a system that's more comfortable and quieter doesn't serve our original purpose if it will indeed use more energy.  I'm still hoping this is just a function of the unusual drought conditions we're having, an off-kilter capacitor as another commentator suggested as a possibility, or perhaps something in the way the two stages are kicking in, and not something in the loop field itself or design.  I'd even feel better if someone told me that the problem is that with the zones evening out the temperature, we're going to have to crank all the temps up to 82 to be equivalent to the average that the old system was probably producing when set at 79 (with thermostat in a hallway with no direct sunlight) and that's why it may be more expensive.  That would be a lifestyle change, in a way, and although it's not one we considered or were told about when the zoning was suggested, we could then feel a little better about it.  However, with that hot EWT (to the hand, at least), I don't think that's all the problem and we're already up to 81 when we previously had the house set at 79.

We would gladly have paid the extra money to have the vertical system if it decreased our energy usage.  The PV system is so expensive that the savings would probably have been more than offset in lower costs for the eventual PV system.  We're not looking at payback necessarily, but rather at how we use less energy and get our monthly bills as low as possible in the future, when energy costs may be higher at the same time our income is decreasing.  However, the accessibility of the flat one-acre and as yet nearly tree-less lot, coupled with the difficulty of getting a well driller out to our away-from-the-city location prompted the installer to suggest the horizontal system.  Our installer does use far more vertical than horizontal loops because much of his work is suburban or city locations, but he has done horizontal loops, of course, so I assume he's knowledgeable about them. 

I'll update when we get temperature measurements.

The paperwork that we have doesn't list the design EWT, but does give the following parameters:  Source Type: Horizontal Closed Loop, Soil Type: Damp Silt/Clay, Pipe Type: 1" IPS PE SDR 11, Pipe Configuration: 2 pipes in trench, Avg. Pipe Depth: 5 feet, Trench Length: 1,485 Feet, Max Source-Cooling: 90 Deg F, Avg.  Source-Cooling: 79 Deg F, Ave Source-Heating: 64 Deg F, Min Source-Heating: 56 Deg F, Deep Earth Temp: 72 Deg F, Surface Swing: 16.0 Deg F, Soil Conductivity: 0.75, Soil Diffusivity: 0.60, Loop Conductivity: 1.89.  Means nothing to me as it's outside my field, but I'm betting that EWT is way higher than 72 or even 88 (72 + 16).  I'm hoping I'm not going to be told that the loops should have been buried deeper. 

Linda

Dewayne Dean (or Geodean),

Thanks for the suggestion about soaking the field with a soaking rod.  That makes sense and seems much faster and ecologically sound than starting at the surface and trying to soak all the way down.  We'll get measurements on the EWT as soon as possible, but we weren't able to locate an LCD kitchen thermometer of the type Engineer suggested in our small town this evening. 

Our contractor listed our soil type as "Damp Silt/Clay." Although there's nothing damp about the central Texas region right now, my husband mostly concurs about the silt, saying that it's more sandy than clay. 

I hesitated to ask for help because I didn't want to discourage others from geothermal systems, and I'm truly impressed with the quiet and comfort.  I know that our installer spent lots of time with us, and as you can tell from my posts, I ask lots of questions.  He was patient and never sounded a wrong note when I asked questions culled from what I had already learned from reading this forum. 

Our bill wasn't much more, but about 13% more and the geothermal system was hooked up only 1 week of that cycle, and we're currently on target to have a bill 24% more this month.  However, I'm glad I did ask as we'll be armed with lots of information and perhaps have gone a long way toward figuring things out before our installer's tech guy is here next week.  When I originally started, I thought perhaps there's something I'm not understanding despite the calculations with the CDD's, the checking in with neighbors to verify that bills went down in accordance with lower CDD's during the billing period.  I'm impressed with how helpful everyone has been on this board and still confident we'll get this sorted out, especially as these posts have prompted the discovery that the EWT appears to be quite warm, seemingly not that different in temperature from the LWT.  It wasn't that way the first week, I remember.  I'm truly believing now that the unusual drought conditions at and after installation may be the problem or a part of it anyway as the loops are perhaps not making close enough contact to discharge all the heat.

Linda

Wow!

We have similary 3 ton/zoned equipment - very similar specs, yours is ClimateMaster, mine is WaterFurnace.

Looking up what 110° EWT would do for me, I see that at 110° my efficiency performance would be cut in half - from 23 to 13 EER.  And that doesn't include pump power - making both numbers a little lower as a result.

So, if your EWT is indeed correct, then my guess is you're running only a little better than an old technology 10 - 12 SEER unit at the moment, which would account for your large KWH consumption.

But, I don't have the knowledge/skills that the experts here do - I look forward to reading their comments.

Meanwhile, I'd be soaking hard the horizontal loop field, while insisting your installer come out and stick in some very accurate instruments to get water flow and water/air deltaT measurements to see what's going on.  Your loop just doesn't look like it's doing its job for some (hopefully solveable) reason.

Best regards,

Bill