I have the following double pole breakers in my new PoN Siemens panel:

  • Heat Pump Water Heater (30A)
  • Clothes Dryer (30A)
  • EV charger (40A)
  • 2x Sub Panel feeds (40A)
  • Heat Pump (40A)
  • Electrical Stove (40A)

I am not able to find CAFCI/AFCI devices for these. GFCI seems to be available.

Should any of these have CAFCI+GFCI (Location: California)? If yes, how is this supposed to happen if the breakers don't exist? (Or possibly, I did not find them)

PS: Circuits were installed long time ago but they all support GFCI/CAFCI (ie, have their own neutrals etc). I still want to be as close to current NEC as possible and this is more a common question.

  • 2
    There's a big difference between tandems (two breakers in one space) and double poles (one breaker in two spaces.) The there's Quads (4 breakers in two spaces.) A picture would disambiguate what you actually have.
    – Ecnerwal
    Sep 24 at 14:34
  • 1
    When were these circuits originally installed? (rules adopted by your jurisdiction at the time of installation are the determining factor) Is the EV hardwired or plug/cord? Sep 24 at 15:52
  • @Ecnerwal Good point, of course I meant double poles. Was late already ;-) Fixed question
    – divB
    Sep 24 at 18:18
  • In the GFCI/AFCI space, NEC is generally very conservative about requiring things which do not exist. Sep 24 at 19:50

1 Answer 1


AFCI is only a thing for 15/20A circuits

AFCIs are only made for 15A and 20A branch circuits as they represent the bulk of the risk that AFCIs are meant to counter (damaged cords, faulty receptacles, and so on).

As to GFCIs...

While 30A and 40A double-pole GFCIs exist, you may not want a GFCI on those circuits for several reasons:

  • GFCI on subpanel feeders may not be appropriate since those subpanels may source circuits (such as lighting) that you don't want to be disabled by a GFCI trip
  • GFCI on circuits for refrigeration appliances (heat pump, HPWH) is problematic because hermetic compressor and inverter input leakage currents are known to cause issues with unwanted tripping of GFCIs
  • GFCIs on stove circuits apparently are also prone to unwanted tripping from normal-operation leakage currents (this and the above point both are causing a major row within the technical committee responsible for NEC branch circuit protection requirements)
  • and EV chargers have their own ground-fault protection built-in, so unless you're installing your EVSE as cord-and-plug connected (in which case the GFCI is required), you don't need to bother.

So, I wouldn't worry about it if I were you.

  • 3
    Also I don't think the listed loads are actually on tandem breakers—at least not as I understand tandems—they're more likely double-pole (i.e. 240V) breakers.
    – Huesmann
    Sep 24 at 13:52
  • Thank you! Huesman is right, I meant double pole breakers (and updated my question). Would you mind including double breakers as part of your reply?
    – divB
    Sep 24 at 18:22
  • 1) Does “refrigeration appliances” also include fridge? 2) Also, I installed CACFI+GFCI dual functions on my 15A light circuits. Was this a bad idea?
    – divB
    Sep 24 at 18:23
  • 1
    @divB -- 1) yeah, fridges generally aren't the greatest in terms of GFCI compatibility either. for normal light circuits, DF breakers are OK, the usual problems come in spaces like shops where you want the tools on GFCI, but having the lighting on that same GFCI is a hazard because a GFCI trip will plunge you into the dark while the saw blade is still spinning from momentum, or the likes Sep 24 at 19:40

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