What is this breaker?

Maybe your electrician installed deep-state fake breakers from communist China?

"

Holy Crap!

What is required is a "high magnetic" breaker. CHOM120HM - HOMELINE CIRCUIT BREAKER 120V .... They are not particularly easy to find, but by substituiting a 2 pole breaker the OP will get a higher magnetic trip rating than a single breaker. Just use one half of the breaker.

I had nuisance trips on my central vac. My panel is a QO, not Homeline, but when I checked with Schneider/Square D they recommended a high magnetic breaker. A standard breaker magnetic trip rating is something in the range of 8 to 10X the breaker rating. High Magnetic breakers are significantly higher - and all 2 and 3 pole breakers are high magnetic. NO AFCI or GDCI breakers are available in High Magnetic Trip versions - see

When I checked the HM breakers were stocked by several suppliers in Quebec but none in Ontario so I used a 2 pole breaker - have not had a false trip since. (over 5 years)

You will notice in the information all breakers OTHER than 15A are also high magnetic - so a 20 amp breaker will also solve the problem but with reduced protection to the circuit.

Dangerous if the downstream wiring is AWG14.

I just ran into that exact discussion in another forum. A guy had a bunch of circuits protected by 15A breakers and wired with 14ga wire. So far, so good. When a receptacle failed, he decided to replace all of the receptacles with 20A commercial units and now he was asking if anyone saw any problems with that.

Well, yes, because a person might notice the 20A receptacle and assume it's a

That's not dangerous so long as the breaker trips at 15A.

It's dangerous when the 14AWG circuit is protected by a 20A breaker regardless of the device (receptacle) rating. Two loads that sum to more than 15A may cause issues (e.g. fire) due to the smaller AWG.

The worst that will happen is that the 15A breaker will trip.

Hi Clare,

Perfect. It looks like the proper part number is HOM115HM (high magnetic as yo suggested). It has been discontinued (20A and up still available), but is still available through distributors

Thank you!

Next step, all the electrician!

It is also a code violation and will solve nothing anyway.

It seems all 'common' breakers have been rated HACR for at least 20 years whether marked or identified as such or not.

A promising approach.

Comment - most breakers have a thermal trip for overload . A small overload can take a long time to trip while the larger the overload the faster the trip ("inverse time"). There is a separate "instantaneous" trip for large overloads - no intentional time delay. The "magnetic" trip does the instantaneous trip (8-10x breaker rating in Clare's post).

The problem appears to be voltage pulses that the AC units are clamping which causes the breaker to trip.

Maybe install a 50kA surge suppressor in the panel?

Actualy only dangerous if the circuit is overloaded

Obvious? Yes, the breaker will trip. Most "15 amp" receptacles are actually rated for 20amps. (because it is legal to install a 15 amp receptacle on a 20 amp circuit)

As per the Canadian Electrical Code 2021, 14AWG copper, in free air with an ambient temperature of 30°C, can manage 25 amps at 60°C and 50 amps at 200°C.Feb 23, 2024

Admitedly this is in FREE AIR - but 25 amps only heats the wire to 60C with a 30C ambient. If the wire is in an insulated wall cavity - specifically if it is foamed insulation, it will run warmer - for sure

- but 20amps is NOT going to cause a fire - all else being equal.

Would I reccomend fusing 14AWG at 20 amps? No. Not generally. However, on a DEDICATED circuit - like for a central vac - with the vac rated at 13.8 amps maximum and protected by it's own internal overload protection device i WOULD be comfortable with the 14awg cable protected by a 20 amp breaker IF a 15 amp High Magnetic breaker was not available for a given panel. Would I prefer #12AWG? - of course. Would I prefer a 15 amp HM breaker on existing 14AWG? Definitely - and since I had room for a 2 pole breaker in my panel - wasting one pole space and a single HM breaker was proving difficult to get my hands on, I chose to install the 2 pole (which is by default in a QO panel High Magnetic Trip).

So just use 20A breakers (no 15s) on #14. It is only dangerous if the circuit is overloaded. Or why not 30A breakers if you can get them cheap.

In Canada

Depends on the length of the circuit.

In the US it can exceed the temperature rating of the insulation which can cause the insulation to fail. Insulation temperature rating is the basis for wire amp rating.

You changed the goal posts with a dedicated circuit.

And if a motor load is hardwired the NEC rules change. The panel breaker is for short circuit protection and may be significantly larger than the wire rating. Overload protection may be at the motor.

The OP would install the 20A breaker on a circuit with multiple receptacles. In the US it is a code violation.

If a 2-pole 15 is HM, the OP has 2 A/C circuits (if the HM reliably doesn't trip).

Oh now the damned things are now tripping on my garage refrigerators!

And foolish

I'm sure there are 120v 20A (5-20P) tools and appliances out there but most manufacturers just jump to 240v versions at that wattage level.