IoTaWatt options

I recently bought a new house and my electrical bills have climbed each month - $250 (Sept/Oct) $279 (Nov), $422 (Dec). It’s winter here in CT and I have oil heat; we were flat out shocked at the last bill as we had made a concerted effort to drive usage down. I suspect a bad device/component somewhere in the home… so I want to track usage.

My problem is that it’s a big house with a bunch of panels. I put together a quick diagram but can also provide photos or descriptions of anything helpful. In a perfect world, I’d like to monitor every breaker in ever box but there are a lot. The main box alone has 23 breakers, the secondary has 14, the tertiary has 8 and the outbuilding/pool have a few each.

How do people with large number of breakers track usage if the IoTaWatt supports 14?

The other thing I’m concerned about is that the house has a 15KVA generator behind the whole thing. Do I just ignore that? Do I care about the 4 DLM modules?

Deeply appreciate anyone’s thoughts/suggestions.

Just in general, a large increase in winter, without electric heat, I’d suspect a hot-tub if you have one, and/or increased lighting with the shorter days if you haven’t converted over to LED everywhere. A lot of folks in New England have added mini-split heat pumps for AC and use them for heat in winter. Even a 12,000 BTU unit can use 24kWh a day. Also, a huge December bill could mean your name is Griswald.

Discovering the large loads, if that’s what is driving your high consumption (as opposed to a load of smaller loads like incandescent or halogen lighting) sometimes is obvious just looking at a plot of usage for a day. They often stick out when plotting usage.

Not much detail in your drawing. Assuming the three sub-panels are fed from the main panel, you might get enough information by measuring the mains and what is going to each of the four sub-panels. That uses 10 of the 14 inputs and leaves you with the ability to monitor 4 or more additional circuit groups in the main panel and possibly the secondary panel if it’s near the main panel.

By subtracting the sub-panels from the mains, you would be able to see the aggregate load is the main panel. Using split-core CTs for the additional 4 inputs, you would be able to move them around over time as you sleuth out the culprits to zero in on any suspected faults.

Should it turn out that there is an unexplained high usage in one of the sub-panels, you can add another IoTaWatt there, but I doubt it will come to that. It looks like you used about 50-60kWh per day.

With IoTaWatt, you can track multiple breakers with one input. There are different ways to do that, and even the different methods can be combined. You can run multiple circuits through one CT, and/or combine CTs into one input with a simple headphone splitter.

I don’t believe the DLMs are an issue.

A picture of the main panel with the cover onto see any labels,and with the cover off showing the internal wiring, might lead to more specific suggestions.

Hi, thanks for the quick reply!
No hot tub and nothing I’m aware of in Dec that wasn’t here in Nov, though there’s the weather changes… Bulbs are LED across the house other than the odd one we occasional run across that aren’t used for weeks at a time, like garage eves.

As you say, I do have an idea of what’s causing it; I’m wondering if it’s HVAC related and plan on focusing on that first. The house has an oil furnace (15 yrs old) and two AC units (9 yrs old) as well as a whole home humidifier. Drier air means that’s running more (2x Aprilaire 500). It also means my sump pumps are running more, since excess water dumps in there. We shut off the humidifiers for other reasons.

Here are some photos of the main box. Close up of top, Box open, labels, box closed.

Looks like:

Mains 2/200A CT
Sub Panel 2/100A CT
Pool Room 1/50A CT Will need to pass both conductors)
Work Room 2/50A CT
Furnace Room 2/50A CT
AC1 1/50A CT
AC2 1/50A CT

That covers the major stuff using 11 inputs, leaving 3. Some options are:
I can’t read the
Range 1/100A CT (Will need to pass both conductors)
Both kitchen circuits 1/50A CT (+ maybe the fridge)
Microwave, Dishwasher and Dining room 1/50A CT

Where I say you will need to pass both conductors through the CT, one has to go the opposite direction like this.

That should break it down well enough that you can see any individual unusual load in the graphs.

Agreed and ordered - thank you for the info/suggestions.