The Loads a Customer Forgets They Own
Why this matters
Ask a customer with a high bill what changed and the answer is almost always "nothing". They are not lying. They are answering a different question: what did we buy, what did we install, what are we doing differently. A freezer that has sat in the garage for eight years did not change. Neither did the heat tape on the well line, or the dehumidifier their son turned to continuous in June. A tech who takes "nothing changed" at face value goes looking for a failed component in the one system they were called about, and either finds nothing or condemns something that was fine. A walk-around list turns the customer's memory into a search the customer can actually do.
Why "nothing changed" is the wrong question to rely on
People inventory their homes by purchase and by habit. Energy is used by things that run, and the two lists do not match. Three patterns account for most of the gap:
- Old loads that got worse. A refrigerator's door gasket fails, a hot tub cover takes on water, a freezer moves from a cool basement to a hot garage. Same appliance, more energy, and nothing the customer would call a change.
- Loads switched on once and forgotten. Heat tape plugged in for a cold snap in January and never unplugged. A block heater on a vehicle that has been parked since winter. A space heater under a desk in a home office that only one person uses.
- Loads that belong to someone else in the house. A household member's new plug-in vehicle, a grow tent, a computer that runs all night, an aquarium. The person calling the shop often does not know the details.
There is a fourth category the list catches by accident: a building or circuit the customer does not think of as "the house". A detached shop, a barn, a well house, a rental unit or in-law apartment fed from the same meter.
The walk-around list
Walk this with the customer, room by room and outside, rather than reading it to them over the phone. Seeing the garage jogs a memory that a question does not.
LOAD WHERE IT HIDES QUICK TELL
2nd fridge/freezer garage, basement warm sides, hum
Dehumidifier basement, crawl hose to drain
Hot tub / swim spa yard, deck cover sagging
Pool pump equipment pad timer pins
Well pump basement, well pit clicks, no tap on
Sump pump basement pit runs when dry
Heat tape / cable pipes, roof, gutters plug at outlet
Block heater driveway, barn cord to vehicle
Space heater office, bath, garage under a desk
EV / plug-in hybrid garage, driveway new car, charger
Grow light closet, basement timer, light leak
Always-on computer office, closet fans at night
Shop / outbuilding detached, same meter wire run out back
How to use the right-hand column:
- Warm sides, hum. A refrigerator or freezer dumps its heat through its sides or a rear coil. Hot to the touch in a hot garage means the compressor is working hard; a freezer whose compressor seems never to stop deserves a measurement.
- Clicks, no tap on. A well pump that starts when nobody is using water is either refilling a pressure tank that is losing charge or feeding a leak. Either one is a cycling load the bill pays for. See related: The Well Pump That Ran Up the Electric Bill.
- Runs when dry. A sump pump cycling during a dry spell points at a high water table, a stuck float, or water from somewhere it should not be coming from.
- Plug at outlet. Heat tape and de-icing cable are usually plugged into a nearby receptacle. If it is plugged in during warm months and has no thermostat or controller, it may be running at full rating.
- New car, charger. A charging cord at a garage receptacle is the tell even without a wall unit.
Two questions sit alongside the list, because they catch what walking cannot:
- Has anyone moved in, moved out, started working from home, or changed shifts? A person home all day in winter can add hours of heating, lighting and cooking to the daytime.
- What else is on this meter? Ask outright whether any other building, unit or tenant is fed from it.
Worked example: an October bill with nothing new
A customer's October bill reads 1,430 kWh for 30 days. Last October was 1,050 kWh, also 30 days. The bill's average temperature is within a couple of degrees of last year, and October is a shoulder month here with little heating or cooling, so weather is not the first suspect. See related: How to Weather-Normalize Two Winters of Bills, if the months had differed.
The difference is 1,430 - 1,050 = 380 kWh over 30 days, which is 380 / 30 = 12.7 kWh a day, which as a continuous load is 12.7 x 1000 / 24 = about 528 W running all day and all night. That is a useful target: you are looking for roughly half a kilowatt of something that runs much of the time, not a brief large spike.
The customer says nothing changed. The walk-around finds two things.
Heat tape on the well supply. Plugged into a pump-house receptacle last January during a freeze and never unplugged. It has no thermostat. The label reads 7 W per foot and the run is 30 ft, so its rated draw is 7 x 30 = 210 W. A constant-wattage tape with no control runs at its rating whenever it is plugged in, so for 30 days that is 210 x 24 x 30 / 1000 = 151.2 kWh. (A self-regulating tape draws less as it warms, which is why reading the label for the type matters before you assume it runs at full rating. This one is constant-wattage.)
The basement dehumidifier. The customer knew it was there; they did not know their son had switched it from a humidity setting to continuous after a damp week in summer. A plug-in meter left on it for 48 hours accumulates 12.0 kWh, which is 6.0 kWh a day and 250 W average. For 30 days, 6.0 x 30 = 180 kWh.
Put the findings against the target:
- Heat tape 151.2 kWh plus dehumidifier 180.0 kWh is 331.2 kWh.
- The bill rose 380 kWh. 380 - 331.2 leaves 48.8 kWh unexplained.
- 48.8 kWh is 48.8 / 1,050 = 4.6 percent of last October's bill.
Month-to-month variation of a few percent is ordinary in a house: an extra load of laundry a week, a few more evenings with the oven on. The two forgotten loads explain 331.2 / 380 = 87 percent of the increase. There is no reason left to suspect the heating system the customer originally called about, and every reason not to touch it.
What the tech tells the customer: unplug the heat tape now and leave it unplugged until it is needed, and have the run looked at before winter because a tape with no controller is due for one. It goes back in for the next freeze only after that, with someone confirming the tape warms along its run and the receptacle does not trip; set the dehumidifier back to a humidity setpoint and see whether the basement holds. What the tech writes down is the kWh each load used, how it was measured, and that the cost of each is that figure x the rate per kWh on the bill. Not a promise of next month's total. See related: How to Write a High-Bill Findings Note for the Customer.
If the walk-around had come up empty
If the walk-around had found nothing, the 528 W target still holds and the next move is the meter: a baseline test that switches known loads off while the meter is watched, or the overnight floor read from interval data to see when it rose. See related: How to Run a Whole-House Baseline Test at the Electric Meter. A floor that jumped on a specific date beats any interview. See related: Smart Meter Interval Data: What the Hourly Record Shows.
If the difference had been a large spike on cold mornings rather than a steady half kilowatt, this list is the wrong tool. That shape points at heating equipment, often backup heat, and it belongs to the diagnostic sequence. See related: How to Diagnose a High-Bill Call in Order.
If the customer had a second meter, a shop or rental on its own service, none of those loads would appear on this bill at all, and listing them would send the customer chasing the wrong account. Confirm which meter serves which building before you count anything.
What the list does not catch
The list finds loads. It does not find faults inside equipment that looks normal from the outside: backup heat strips running when the thermostat says they should not, a water heater element that runs because a thermostat stuck, a refrigerator whose defrost system has failed so it runs without stopping. Those show up on a measurement, not a walk-around, and they belong to the causes list. See related: Why a Bill Rises: The Causes That Are Not the New Equipment.
It also cannot settle anything by itself. Every item on it becomes a finding only once it is measured or its rating is read and its run time is known. A hot tub on the deck is a suspect, not a cause.
Walking it without creating a hazard
The walk-around is looking and asking, not working. Do not open an equipment bay on a hot tub, a pool pump housing or a well control box to see what is inside; if you need to know what a motor draws, a clamp on the supply conductor at an accessible point is measurement work for someone qualified to do it. If a heat tape run is cracked, taped over or plugged into an extension cord, tell the customer to unplug it at the receptacle and leave it unplugged until an electrician has found and fixed the damage. If a sump pit or well pit is uncovered, keep children and pets away from it and do not reach in; a pit with water and a pump in it is a shock hazard until the circuit is proved dead by someone qualified to do that.
References
- See related: Standby and Phantom Loads: What Is Worth Chasing
- See related: Utility Bill Spike - Source Isolation Decision Tree
- See related: Reading Customer's Electric Bill Reference
- See related: How to Take a High-Bill Call at the Office
- Manufacturer installation and labeling instructions for heat tape and de-icing cable, for wattage per foot and control type