Considering effectiveness of the Arc Fault circuit protection devices

[Puysparky]

Is it likely that installing an arc fault circuit breaker can protect knob and tube installation?
Are any insurance companies recognizing the technology as solving the arc problems of failing knob and tube installations? Do you know of any companies that are accepting the AFCI as acceptable for protection for knob and tube installation failures? My residential customer has CH Cutler Hammer breakers.
Tom McMullen

 

[Little Bill]

It's not been proven to me to even protect modern wiring, other than theory!

 

[Dennis Alwon]

It seems that an afci breaker will partially protect the wire of K&T wiring itself, however, afci can protect from arcing within the jb at a device.

It would appear that the afci couldn't do much for parallel arc but may help with series fault. Unfortunately, this is not solving the issue of K&T wiring that scares insurance companies.

IMO, the insurer will not accept K&T wiring even with afci protection.

Change companies. There are companies who will insure the house with K&T just as there are companies who will insure houses wired with aluminum

 

[romex jockey]

A decade and 1/2 ago , a local inn was being confronted with their 2nd flr K&T wiring via their insurer.

They had just renovated with $$$$ wallpaper , etc , but had maintained the original mechanicals (plum & elect) for reasons of antiquity (big mistake)

Yours truly installed an afci breaker for the whole 2nd floor 'one circuit does all' K&T circuit , my AHJ at the time (now retired) gave it the hairy eyeball , stating that if it was approached by the insurance co., then it would need to be validated by the insurance co.

After some phone tag ado, they conceded , which also meant i could ride around with the magic 'lectrical widget' that could cure all 'lectrical woes in one simple service call stop

Unfortunately this euphoric epitome of technological wonder was not long lasting , the insurance cabal came to their senses and poo poo'd afci technology after a year @ said Inn, the state of VT condemned K&T across the board w/o any hope of salvation (exposed, megged, ferget it!)

Alas , the insurance cabal, who own everything on this rock,and probably out past saturn, made the call in both situations. The moral of the story being, one may meet 'code', yet not meet insurance standards

~RJ~

 

[mbrooke]

Well, surprisingly insurance companies do not seem to be endorsing these like some holy grail...

And to be honest, unless that K&T was touched by hacks I would sleep better at night with it in the wall than old cloth NM cable from a fire hazard perspective. Often K&T has better splices than wiring years latter, stands up to over fusing better, and insulation fraying poses less hazard.

 

[Sahib]

It would appear that the afci couldn't do much for parallel arc but may help with series fault. Unfortunately, this is not solving the issue of K&T wiring that scares insurance companies.

Parallel fault eventually develops into line to ground fault. So a combination of gfci and afci has a better chance of convincing the insurance company. But for that to happen, an EGC also be there in K&T!