How this calculator works
The calculator converts three possible new loads to amps at 240 V and compares the sum to spare amps you typed:
heat pump A = nameplate VA / 240
dryer A = 24 if electric, else 0
EVSE A = current you typed × 1.25
need = heat pump A + dryer A + EVSE A
talk = spare − need (overshoot or leftover)On a 6,000 VA heat pump (25 A), an electric dryer (24 A placeholder) and a 32 A EVSE (40 A at 125%), need is 89 A. Against 40 A spare, that overshoots by 49 A. Against 100 A spare, 11 A still shows as leftover. Both sentences are illustrative. Neither is a stamped load calculation, and neither is a restamp of the optional calculation in 220.82. That work already lives on the load calculator.
If spare is 0 and the new loads are 0, you will see a leftover of 0 A. That is "you typed nothing," not a pass. Type the spare from the load calculator before you trust the talk line.
What each input means
| Input | What it is actually asking |
|---|---|
| Spare amps | What you have left on the existing service after the house-shaped demand. From the load calculator "against existing service," or from an electrician. 0 means no spare. It does not mean unknown. |
| Heat pump VA | Nameplate volt-amperes. Divided by 240 to get amps on this form. Use the larger of heating and cooling if both are on the plate, as you would on the load calculator. 0 if you are not adding one. |
| Dryer | Gas is 0 A. Electric is a 24 A placeholder, not your nameplate. If the plate is very different, put the real VA in the load calculator rather than arguing with 24 here. |
| EVSE current | Amps at 240 V the charger will draw, then ×1.25 as a continuous load. 0 if none. Same 125% as the circuit estimator. |
Worked examples
Including one where the naive answer misleads, which is the example most calculators leave out.
A heat pump only, on spare you actually have
Spare 40 A from the load calculator, heat pump 6,000 VA, dryer gas, EVSE 0. Need = 6,000 / 240 = 25 A. Talk: 15 A still spare on these figures. That leftover is not a permit, and it is not room for the EV you have not typed yet. It is a reason to keep going with an electrician rather than to assume 40 A spare is a 40 A shopping budget.
Heat pump, electric dryer and a 32 A charger
Spare 40 A, heat pump 6,000 VA (25 A), dryer electric (24 A), EVSE 32 A × 1.25 = 40 A. Need 89 A. Talk: these three loads overshoot the spare you typed by 49 A. That is a service or load-management conversation, not a cart with three appliances in it. Lowering the EVSE to 16 A (20 A at 125%) is one of the things an electrician can price. This page will not pick it for you.
The one where "the panel is 200 A" misleads
A 200 A label on the dead front, spare typed as 200 because that is the number on the door, then heat pump + dryer + EVSE added as if the house currently draws nothing. The naive answer is plenty of room. The load calculator is there to stop that. Existing range, HVAC, water heater and general load already occupy most of a 100 A or 200 A service. Spare is the leftover after that, not the rating printed on the box. Type the leftover. If you have not run the load calculator, this page is early.
What changes the result
EVSE current is the lever that most often changes the talk line, because of the 125% multiplier. 24 A of charger current is 30 A of demand. 32 A is 40 A. 48 A is 60 A. Dropping from 32 A to 24 A is 10 A back, which is sometimes the difference between overshoot and leftover on a tight service. It is also a slower charge. The EV selector is where miles and hours say whether that slower charge still covers the day.
Switching dryer from gas to electric adds a flat 24 A on this form. That is a lot, on a 100 A service that already has a heat pump. Keeping a gas dryer is a real electrification choice, not a moral failure, and this tool will show it as 0 A.
Heat pump VA moves one-for-one with the plate. A 3,600 VA unit is 15 A. A 12,000 VA unit is 50 A. Use the plate, not a "3-ton" rule of thumb we would have to invent.
Local considerations
Which edition of the NEC your jurisdiction adopted, whether load management is accepted in place of a service upgrade, and what the utility requires for a service change are local. This page will not list them by state. The spare figure is yours. The new demand is nameplates and a 24 A dryer placeholder. The decision is the electrician, against the adopted code, not this form.
When not to use this
Do not use this as a stamped load calculation, a permit, or a reason to open the panel. It is not 220.82. It cannot see existing loads you left out of the spare number, a heat pump whose nameplate is in a different unit, or a panel with no spaces.
Do not type the service rating as spare. Spare is leftover. The load calculator exists so you do not have to guess it.
Do not use a leftover here as proof you can add all three tomorrow. Load management, diversity and the adopted edition belong with a licensed electrician.
HyreElectrical does not perform electrical work. Matching is still being built. The enquiry form is not a booking.
Related on this site
- Panels and capacity on the homepage Capacity is not age, and a full panel is a different shortage from short amps.
- A new appliance needs a circuit Ranges, dryers, HVAC and EV: the plate tells the electrician what to build.
- How electrical cost moves Panel capacity is the most common hidden multiplier.
- Find electrical help An enquiry, not a dispatch.
Questions this calculator answers
- Can my panel handle a heat pump, a dryer and an EV charger?
- Only against spare capacity you actually have, calculated for this house. This tool subtracts new 240 V demand from spare amps you type. It will not invent the spare. Run the electrical load calculator first, or use a figure an electrician already gave you. "The panel says 200 A" is the rating of the box, not the spare.
- Is this a NEC 220.82 load calculation?
- No. 220.82 is the optional whole-house calculation, and the load calculator on this site is already shaped like it (first 10 kVA at 100%, remainder at 40%, HVAC at 100%, EVSE at 125%). This page does not restamp that article. It only asks whether three new 240 V loads fit in the leftover you brought with you.
- Why is the electric dryer 24 A?
- It is a planning placeholder for a typical 30 A, 240 V dryer circuit at 80%, not your nameplate. If you have the dryer plate in amps, you can still use this as a coarse check, then put the real VA into the load calculator. Gas stays 0 A here because a gas dryer is not a new 240 V demand.
- Why is the EV charger multiplied by 1.25?
- Because a charger is a continuous load in the model-code shape: the circuit is planned at 125% of the current you set. A 32 A EVSE is 40 A of demand on this form, the same 125% the circuit estimator uses. Typing 32 and reading 32 is how people think a 200 A panel has room it does not.
- What is spare amps?
- Existing service amps minus the calculated demand on the load calculator, or a spare figure an electrician already wrote down. If the load calculator said the house is already over the service, spare is not a number you pad. Type 0. An empty box is treated as 0 by the arithmetic, which means "no spare," not "I do not know."
- The result says I still have spare. Can I add all three?
- Not from this page. The leftover is illustrative. Diversity, the adopted NEC edition, load management, and whether those three loads actually coincide are the electrician calculation. A positive leftover here is a reason to have that conversation, not a permit.
- The result overshoots. Is that a service upgrade?
- It is a service or load-management conversation. Whole-house load control, a lower EVSE current, keeping the dryer on gas, or a service change are different jobs. This tool will not pick one. It will not open the panel either.
- Do I still need the load calculator if I use this?
- Yes. This page is downstream of it. Without a house-shaped demand number, spare is a guess, and a guess plus three new 240 V loads is how "we electrified the house" becomes a dark house on a cold evening.
- Does panel space matter as well as amps?
- Yes, independently. A 200 A panel can be full. Count spaces on the panel space checker. Heat pump, dryer and EVSE are usually three separate 240 V two-pole breakers. Spare amps with no spaces is still a project.
- Does HyreElectrical do electrification work?
- No. HyreElectrical does not perform electrical work, size heat pumps, or sell chargers. Matching is still being built. The enquiry form is not a booking.
Sources and methodology
Figures dated 26 August 2026. Last reviewed .
- NFPA 70, National Electrical Code, Article 220 (National Fire Protection Association, retrieved 2026-08-26. Cited as the model code. The load calculator on this site is shaped like the optional calculation. This page is not a reprint of 220.82. Confirm the edition your jurisdiction adopted.)
- Charging electric vehicles at home (U.S. Department of Energy, Alternative Fuels Data Center, retrieved 2026-08-26. Cited for home charging as a household electrical load. Current and 125% live on the circuit estimator, not in an AFDC amp table.)
- Home electrical safety guidance (Electrical Safety Foundation International, retrieved 2026-08-26. Cited for the standing rule that service and panel work are not DIY.)
Related
- Electrical load calculator The house-shaped number. Spare amps come from here, or from an electrician.
- Panel space checker Amps and spaces fail independently. Three new 240 V loads want spaces as well as spare.
- EV charger selector Whether Level 2 is even the next conversation, from miles and hours.
- EV charger circuit estimator 125% of the current you set, then the run. Same 125% this page uses on EVSE.
- Electrical project cost If this overshoots, type the service or load-management bid. No national average.