Choosing Which Circuits to Back Up — Your Must-Run List
Last verified: September 2026
How to build a smart 'must-run' list for your transfer switch — safety first, then essentials, then comfort — without guessing at numbers. Want help sorting it out? (330) 200-8042.
Choosing Your Circuits, at a Glance
Before an electrician wires your transfer switch, you decide which circuits it will back up — your must-run list. Build it by priority: life and safety first (medical equipment, heat, a sump pump, well water), then daily essentials (fridge, a few lights), then comfort if there's room. Leave the power-hungry giants off a portable generator. There's a printable 29-page version up top.
Common Questions
1 How do I decide which circuits to back up?
Work down a priority ladder: life and safety first (medical equipment, winter heat, sump pump, well water), then daily essentials (fridge, some lights, phone charging), then comfort — stopping when your generator's capacity is used.
2 What should I leave off the list?
On a portable generator, leave off the giants: central air conditioning, an electric range, an electric water heater, and the clothes dryer. They'll overload a modest generator.
3 Does the fridge need to be on the switch?
Not necessarily — a fridge has a plug, so many folks power it with a safe outdoor-rated cord and save switch circuits for hardwired items like the furnace and pump.
4 How many circuits should I back up?
Enough to cover your true musts and fit your generator — no more. Start from a prioritized list and let the generator's capacity set the limit. See our sizing guide.
5 What if my needs change later?
Adding a circuit later usually means another electrician visit, so it's worth including a spare position now if your budget allows — cheap insurance against forgetting something.
6 What do people most often forget?
The well pump and the sump pump. If either applies to your home, put it high on the list early — they're the omissions folks most regret.
Would You Rather I Just Help?
Building a smart, right-sized must-run list is one of the most useful things I help with — and I have no reason to pad it. I'll walk your home, sort your needs, and help you bring a clear list to a licensed electrician. $99 flat for a visit.
Would you rather I just do this for you?
No shame in it — plenty of folks would rather hand it off, and that's what I'm here for. I'll come to your home, set it up right, and make sure it's working before I leave. Flat $99 per visit — no jargon, no upsell, and every visit is 30-day come-back-free.
Not a hardware job? I can often fix it remotely for $49 — a secure screen-share, up to 2 hours, that you watch the whole time and can end whenever (included free for $39/mo Support Plan members, and it counts toward the $99 if it turns out I need to come out).