CRAP, PO caused me another safety problem!!!

Gary LaBombard · June 23, 2016, 10:01:26 AM

OK, today working on my electrical panel set up per previous post. All existing wires were traced and marked and found out that my two roof airs are wired with 14 ga. copper wire!! I believe these should be no less than 12 ga for safety and help prevent overheating. Anyhow taking off the connections on the AC units I see the wires are run through the overhead framing and only tape was used to coat the wires for extra protection from chaffing on the frame apparently. The entire ceiling is glued on to plywood or paneling or something!! Christ!! what to hell to do now is my dilema, I know what I have to do but this again is discouraging. Could sure overheat the wires on a hot day like today using both airs I am sure. So if I sound pissed, I am!! PO really screwed me good and I hope he sees all these post over the years. CRAPPPPPPPPPPP

you can never trust another converter with a used bus it seems. they cheat at the damnedest places such as this. I could easily had a fire or worse, you never know what you got until you have to repair or replace something that the PO owner did. Just my thought on this. Just pissed off too I guess.

Gary Hatt - Publisher BCM · June 23, 2016, 10:33:43 AM

Gary,

I was an electrician in a previous life and probably the safest thing you can do is to run your wire thru what they call BX cable as you can view here. http://www.homedepot.com/p/Southwire-100-ft-12-2-Solid-CU-BX-AC-Cable/202819636

Or run it thru EMT Conduit here. http://www.homedepot.com/p/Allied-Tube-Conduit-1-2-in-EMT-Conduit-101543/100400405

This would probably be the ultimate because even using a grommet can wear thru after time.

Using BX cable kind of sucks, dealing with the BX type connectors, but code requires it to be used in some cases where something could cut thru the cable and cause a shock hazard.

Regarding using extension cords to run wring as was mentioned in a recent thread has the same problems according to some folks, it too can chafe thru after a while, but my Eagle was wired that way and I have no plans on re-doing it.

Gary

Lin · June 23, 2016, 10:36:14 AM

I think that you are right in preferring at least 12 gauge wire for the AC's. However, 12 gauge is required for a 20 amp circuit. 14 gauge is okay for a 15 amp circuit. What size breakers do you have? If the AC's are running okay on 15 amp breakers, it may be alright. Are you able to check if the wires are actually getting hot?

Gary LaBombard · June 23, 2016, 10:42:36 AM

I have no choice but to remove the ceiling in the front and back of bus. And as you suggested Gary, Thanks by the way, but run BX cable for safety. I just tired of all this crap.

No Lin I am unable to see if the wires get hot or not as I am installing new power panels etc. to have new system. But was hoping the wiring already installed was sufficient but that fell through as noted here. I can install any size breaker I need in my new box, have not installed them as yet, I just would never rest good knowing of this situation going through framing and burrs still exist in the hole where I can see. I know it will be impossible to pull new wires so I just have to bite the bullet and take it all down or where I have to and knowing my luck, I will have to take the whole freakin ceiling down. I need peace of mind after all this time of converting this bus.

Oonrahnjay · June 23, 2016, 11:06:38 AM

Quote from: Gary LaBombard on June 23, 2016, 10:42:36 AM
I have no choice but to remove the ceiling in the front and back of bus. And as you suggested Gary, Thanks by the way, but run BX cable for safety. I just tired of all this crap.

No Lin I am unable to see if the wires get hot or not as I am installing new power panels etc. to have new system. But was hoping the wiring already installed was sufficient but that fell through as noted here. I can install any size breaker I need in my new box, have not installed them as yet, I just would never rest good knowing of this situation going through framing and burrs still exist in the hole where I can see. I know it will be impossible to pull new wires so I just have to bite the bullet and take it all down or where I have to and knowing my luck, I will have to take the whole freakin ceiling down. I need peace of mind after all this time of converting this bus.

Gary, if the 14 ga wires go to the right place, can you use them to pull the new, larger-gauge wires? One thing that might work (if there's too much friction to pull new wires with the old) is to pull a thin "fish"* wire into place when you pull out the 14 ga and then use the thin fish to pull your new 12 ga in. I hate to think of you having to remove all the ceilings etc. if you don't have to. BTW, will you need three-conductor wire (hot, neutral, ground) for this circuit?

(* Sometime you can rent or borrow a flat fish like a metal spring that works really well, it will slip into and around the places you need and they have a loop of the end that makes it easy to attach the wire you're pulling, and the loop helps the fish guide through corners, etc. Of course, if you have burrs and sharp corners, you'd only be putting new, expensive cable in a bad place so that might mean you have get in there. Sorry to hear this but it's good you're making it safe.)

eagle19952 · June 23, 2016, 11:46:57 AM

i would certainly try a fish tape... with the current wires in place.. you may then be able to feed a non metallic conduit...

DoubleEagle · June 23, 2016, 05:23:29 PM

If the wire passes through holes in the ribs and/or makes turns, you are not likely to be able to pull new wire through whether Romex or BX. Redoing the ceiling will allow you secure the wires with no chafing points, and to check the quality of the insulation. Since corners might have been cut with the wiring, what are the odds the insulation is ideal? Remember the joy of a conversion is doing it, not going anywhere with it; that is just a bonus.

Skykingrob · June 23, 2016, 05:30:43 PM

As others have suggested use the previous wires for pulling either a new fishwire or new wire. If that fails, rather than pull the whole ceiling down, can you just cut an 1-3" wide slot down the ceiling to unveil the existing wire and then go back with some kind of decorative covering over that later? Decorative like a wide strip of stained wood, cloth covered wood, preglued kitchen shelf paper over wood in a complementary pattern, etc. If that isn't an option, then make a new tunnel of your own to run all new wire through and cover it decoratively. Would save you a ton of work if you can think of something like that. If you post pics, may be we can help think of something that will save you tons of work and further frustration.

Rob
Missouri

blue_goose · June 23, 2016, 05:38:31 PM

Don't make work for yourself that you don't need. The airs only pull 13 amps at the most, 14 wire is good for that. Nothing moves in an Eagle so the wires won't chafe, If it is stranded wire forget what I said. If it is solid will be fine.
Jack

belfert · June 23, 2016, 05:57:08 PM

My 15,000 BTU rooftop units are wired with 12 AWG wire to 20 amp breakers. Even the 20 amp breakers trip when it is 107 degrees in the desert,

Gary Hatt - Publisher BCM · June 23, 2016, 06:28:44 PM

My MCI has the same problem, my breakers trip when the A/C units are working hard too, but only when it is over about 105F outside. If you have a long run from your A/C unit to your breaker panel you may want to bump it up to 10 AWG wire so there is less resistance. It is not per code, but it is fine as long as you stick with a 20 AMP breaker. By increasing the size of the wire, it will also keep the wire from overheating as well.

But then again, if this becomes an ongoing issue, you may want to check the AMP draw on that line. I believe it should draw about 14A after it starts, but the problem it can draw up to 18A starting. And if there is still head pressure, i.e. if you shut it off then turn it right back on again, this can cause it to draw more than 20A thereby tripping the breaker. But then again, your mileage may vary depending on your unit.

Maybe a "real" electrician can step in here and correct me if I am wrong but has been my experience.

DoubleEagle · June 23, 2016, 06:30:32 PM

Gary did not say what size his A/C's are, but having 12 gauge wire gives an extra margin for starting-up amperage, and for safety.

kyle4501 · June 23, 2016, 06:45:23 PM

Is there any way you could use the plastic surface mount conduit to run the new wire to the AC units
https://www.codale.com/index.jsp?path=product&part=3916

This way you could abandon the questionable wiring & not have to tear out anything to run new wiring.

Lin · June 23, 2016, 06:48:32 PM

The AC's tripping the breaker in extreme heat conditions is not merely a wire size issue. Though I would hope that they would continue to work at least past 110, there is a limit on how much heat they can deal with.

Gary Hatt - Publisher BCM · June 23, 2016, 07:03:14 PM

My units are 15,000 BTUs. Also trapping the wire in a very tight space will not let the heat dissipate if it does heat up, whereas running it in BX cable will let it breath a bit, but generally no steps are taken to not do this as many people wire their buses then blow in insulation all of the time. Wires are not supposed to get hot if they are sized properly but the 15,000 BTU A/C units push the limits of a 20A breaker in my opinion. But then this only happens when they first start up.