Here is a conversation we have several times a month. A homeowner in Arlington Heights or Evanston gets three heat pump quotes. Two of them are within a few hundred dollars of each other. The third is $3,000 higher, and it is the only one that mentions the electrical panel. Guess which one is telling the whole truth.
Adding a heat pump adds electrical load to a house that may not have been designed for it. In neighborhoods with 1950s and 1960s housing stock — which describes a lot of both towns —100-amp service is still common. This article walks through how much load a heat pump actually adds, how to tell whether your panel can take it, what an upgrade costs, and three legitimate ways to avoid the upgrade.
How Much Electrical Load Does a Heat Pump Really Add?
It depends heavily on the type of system and whether you keep a fuel backup.
| System Type | Typical Circuit | Added Demand Load |
|---|---|---|
| 3-ton cold-climate heat pump, dual fuel (gas furnace backup) | 30 – 40A / 240V | ~6 – 9 kW |
| 3-ton heat pump with 10 kW electric backup heat | 60 – 70A / 240V | ~14 – 18 kW |
| 4-ton heat pump with 15 kW electric backup heat | 80 – 100A / 240V | ~20 – 24 kW |
| Ductless mini-split, 2 – 3 zones | 20 – 30A / 240V | ~3 – 6 kW |
Notice the pattern: the electric backup heat strips, not the heat pump itself, are what blow up the load calculation. A cold-climate heat pump paired with your existing gas furnace — a dual fuel system — adds a fraction of the load of an all-electric setup, and it is also the configuration that performs best in Chicago winters.
Can Your Existing Panel Handle It? The Honest Test
The real answer comes from a load calculation, not a glance at the breaker panel. An electrician totals your home’s general lighting load, small appliance and laundry circuits, fixed appliances, the largest of heating or cooling load, and any EV or other significant loads, then applies code demand factors.
Rough guidance from the calculations we run every week:
- 100-amp service, gas furnace, gas water heater, gas range, no EV: often has room for a dual fuel heat pump. Frequently yes.
- 100-amp service with electric range, electric dryer, and central AC: usually tight. Often no, unless you use load management.
- 100-amp service plus a planned EV charger: plan on the upgrade.
- Any all-electric heat pump with 10 kW+ strip heat on 100-amp service: essentially always requires the upgrade.
- 150 or 200-amp service, gas backup: almost always fine.
Also worth checking regardless of capacity: if you have a Federal Pacific Stab-Lok or Zinsco panel, it should be replaced no matter what equipment you are adding. Those panels have documented failure-to-trip problems.
What the Panel Upgrade Costs
| Scope | Typical Cost in Arlington Heights & Evanston |
|---|---|
| 100A to 200A panel upgrade, overhead service, panel in same location | $2,400 – $3,800 |
| 100A to 200A with new meter socket and mast | $3,200 – $4,800 |
| Underground service upgrade (trenching, utility coordination) | $4,500 – $8,000 |
| Panel relocation (basement to exterior or vice versa) | +$800 – $2,000 |
| Dedicated heat pump circuit only (panel has capacity) | $450 – $1,200 |
| Smart electrical panel or load management device | $800 – $3,500 |
Add permit fees and, in some cases, a utility coordination window that can stretch the schedule by a week or two. Evanston’s older neighborhoods with underground service and tight side yards tend to sit toward the upper end; Arlington Heights subdivisions with straightforward overhead drops tend toward the lower.
Three Ways to Avoid the Upgrade
1. Go dual fuel
Pair a cold-climate heat pump with your existing gas furnace. The heat pump handles the vast majority of annual heating hours; the furnace takes over below a switchover point typically set between 15°F and 25°F. You get most of the efficiency benefit, you keep a proven backup for a Chicago cold snap, and you skip the electric strip heat that drives the load calculation. For most homes in our service area, this is the recommendation on the merits — the avoided panel work is a bonus. See our heat pump page for how these systems perform locally.
2. Use a load management device
UL-listed load controllers and smart panels prevent two large loads from running simultaneously — for example, locking out the EV charger while heat strips are energized. Code permits these devices to be used in load calculations, which can legitimately keep a 100-amp service compliant. Cost is typically $800 to $3,500, so compare against the $2,400+ upgrade before assuming it saves money; sometimes the upgrade is the better long-term buy.
3. Right-size the equipment
Oversized systems are the norm in replacement work because contractors match the old nameplate instead of running a Manual J calculation. A properly sized 2.5-ton system instead of a reflexive 4-ton not only reduces electrical demand — it dehumidifies better, runs quieter, and lasts longer.
Rebates and Incentives Worth Checking
ComEd and Nicor incentive programs for high-efficiency heat pumps change year to year, and some utility programs also offer support for electrical service upgrades tied to electrification. Illinois programs have historically layered on top of manufacturer promotions. Verify current amounts before you sign, and make sure paperwork is submitted in the required order — several programs require pre-approval.
How to Budget the Whole Project
A realistic all-in range for an Arlington Heights or Evanston home:
- Dual fuel heat pump added to an existing furnace, panel has capacity: $9,000 – $15,000
- Dual fuel heat pump plus 200-amp panel upgrade: $12,000 – $19,000
- Full system replacement (heat pump + new furnace) plus panel upgrade: $17,000 – $26,000
Sunbit and PowerPay financing can spread these across manageable monthly payments, and doing the HVAC and electrical work under one contractor avoids the finger-pointing that happens when two trades meet at a disconnect box.
Frequently Asked Questions
Will my 100-amp service definitely fail with a heat pump?
No. Many gas-appliance homes with 100-amp service handle a dual fuel heat pump fine. Only a load calculation tells you for certain.
Does a panel upgrade lower my electric bill?
Not directly. It adds capacity and safety, not efficiency.
Can the panel upgrade happen the same week as the heat pump install?
Usually yes, and it should. We sequence the electrical inspection ahead of HVAC startup.
How long is the power out during an upgrade?
Typically four to eight hours on the day of the changeover, depending on utility coordination.
Do I need a permit?
Yes, in both Arlington Heights and Evanston, for the electrical service and for the mechanical work.
Get One Quote That Covers Both Trades
MMDS does heat pump installation and licensed electrical work in-house, so your heat pump quote includes the panel reality instead of hiding it. We run the Manual J and the load calculation before we give you a number.
Call (847) 221-6280 or book a free in-home assessment.