Flexible whips - where needed?

[AntonLargiader]

Basic question that I haven't seen addressed. Where are flexible whips required?

The main reason I'm asking is because I realized that pretty much every water heater and pressure tank that I've seen has NM-B hanging free in the air feeding it, and even my dishwasher had NM-B making more or less a flexible cord when I slid it out of the counter. None of these seem to meet the support requirements but they are commonplace.

Compressors, I can see the increased need due to vibration, although the pre-made MC whips I recently saw at Lowes seemed to be solid wire.

What's the simplest code-compliant way to wire water tanks and heaters? It looks like there is a maximum 18" unsupported length applying to these sorts of appliances, and even within that there is the fact that NM-B in that situation seems exposed to damage.

 

[mike93lx]

Curious to hear answers on this. I've only wired one water heater and I used a liquidtite whip for it.

On dishwashers, I have tended to use NM-B, but decided after the last one, when I need to do another, I'll put a receptacle in and wire up a cord. It always ***** messing with the wiring connections on the floor under a DW

 

[AntonLargiader]

I wired up a dishwasher cord, too. We were having some troubles with it (no more LG! Ever!) and it made disconnecting power very easy. I also made a cord for my furnace/AHU, so I can easily run it from an inverter.

 

[jeepxj]

Curious to hear answers on this. I've only wired one water heater and I used a liquidtite whip for it.

On dishwashers, I have tended to use NB, but decided after the last one, when I need to do another, I'll put a receptacle in and wire up a cord. It always ***** messing with the wiring connections on the floor under a DW

bluetooth supports

 

[u2slow]

Dishwashers and tank heaters are commonly done with AC cable whips up here. (Our AC has a #14 or larger copper bond wire.) NM shouldn't be exposed, so if used, it's usually sleeved with metallic flex.

 

[kaymccampbell]

For non moving items, I like MC to a box on the wall or ceiling. Except in moisture areas, then it's liquidtite. For obvious vibrators, like compressors , I make sure I've got stranded wire. Dishwashers get a chunk of SJ with a plug. I only use exposed NM -B to hotwire something in an emergency.

 

[wyliesdiesels]

Dishwashers and tank heaters are commonly done with AC cable whips up here. (Our AC has a #14 or larger copper bond wire.)

all AC/armor clad cable has a bonding wire....

NM shouldn't be exposed, so if used, it's usually sleeved with metallic flex.

why is that? and sleeving it in FMC is more work and costlier than just running THWN in the FMC...

 

[u2slow]

all AC/armor clad cable has a bonding wire....


why is that? and sleeving it in FMC is more work and costlier than just running THWN in the FMC...

I seem to recall some discussion about differences with american and canadian AC cable.

When NM is a dedicated run from the panel it's easier to slip flex over the last few exposed feet than to have another JB, and change over to other wire.

 

[alfredeneuman]

The Code here (NEC) treats NM,AC,&MC cables, and ENT....As well as all forms of flex conduit the same.
Protection from physical damage is required for all.

 

[AntonLargiader]

The Code here (NEC) treats NM,AC,&MC cables, and ENT....As well as all forms of flex conduit the same.
Protection from physical damage is required for all.

So how are water heaters, pumps, and other free-standing hardwired appliances wired in a compliant manner where you are? That's what I'm asking.

 

[alfredeneuman]

That's one of those damned if you do, damned if you don't situations
A 90 degree connector on top of a water heater to the wall and another 90 degree connector to the box on the wall is IMO the best way.

 

[AntonLargiader]

With Romex? That's what I always see. Do you think it's compliant?

Don't get me wrong, I'm not trying to point fingers. I'm just surprised to realize that so many installations seem to be noncompliant and NOBODY cares. Not just the folks here on IfItsWorthDoingItsWorthOverdoing.com but the inspectors and everyone else. Free floating Romex seems to be the standard, even if it's exposed and not secured 18" after leaving the J box.

I had gotten the sense that liquid-tight with THHN from the water tank to the disconnect would be legal but now you're saying that all flex, I assume that includes liquid-tight, need protection. Isn't pretty much every outdoor unit in the country connected with liquid-tight?

 

[dchawk81]

Basic question that I haven't seen addressed. Where are flexible whips required?

I would defer that to the **********' expertise.

 

[alfredeneuman]

I assume that includes liquid-tight, need protection. Isn't pretty much every outdoor unit in the country connected with liquid-tight?

Like I said, it's pretty much a damned if you do, damned if you don't situation

 

[sparky 1971]

There is no definition of protected from physical damage, leaving it wide open for interpretation. Around here, water heaters get plain old 1/2 flex with #10 THWN in them. I've also seen plenty of older installs with romex and even a few with cords and 6-30's. Some might say that the odds of romex getting damaged is low so they might let that go. Nothing is damage proof. I've seen smashed RMC, pulled off the wall, broken couplings, the whole nine yards. What about air conditioners? 90% of them have a LFNC running to them from the disconnect with no straps. All it would take is something falling on it and it's getting ripped out of the connector. EMT isn't really all that safe from destruction, but I use it every day (almost).

 

[wyliesdiesels]

With Romex? That's what I always see. Do you think it's compliant?

Don't get me wrong, I'm not trying to point fingers. I'm just surprised to realize that so many installations seem to be noncompliant and NOBODY cares. Not just the folks here on IfItsWorthDoingItsWorthOverdoing.com but the inspectors and everyone else. Free floating Romex seems to be the standard, even if it's exposed and not secured 18" after leaving the J box.

I had gotten the sense that liquid-tight with THHN from the water tank to the disconnect would be legal but now you're saying that all flex, I assume that includes liquid-tight, need protection. Isn't pretty much every outdoor unit in the country connected with liquid-tight?

 

[u2slow]

Just because a cable is visible/exposed doesn't always mean it's prone to damage. Location and elevation factor in. A metallic cable armour or flex can take more abuse than a thin plastic one.

 

[acer66]

Just because a cable is visible/exposed doesn't always mean it's prone to damage. Location and elevation factor in.

Yeah, around here most water heaters with a tank are wired with nm-b wire that goes straight up between the pipes passing inspection.

 

[mike93lx]

Yeah, around here most water heaters with a tank are wired with nm-b wire that goes straight up between the pipes passing inspection.

Zip tying to the cold supply gives you active cooling and let's you drop down a wire size, saving money.








/s

 

[larry4406]

I'm sure the thread title caught the attention of @PelicanPines

 

[PelicanPines]

I'm sure the thread title caught the attention of @PelicanPines

Yes it did... I prefer NON-flexible whips.

 

[welder4956]

"334.15(B) Protection from Physical Damage. Cable shall be protected from physical damage where necessary by rigid metal conduit, intermediate metal conduit, electrical metallic tubing, Schedule 80 PVC conduit, Type RTRC marked with the suffix -XW, or other approved means."

The words "...protected from physical damage where necessary..." seem to leave it open to interpretation by the installer and inspector. I suppose if the water heater is in a closet, or the wire is not out where people or objects would be contacting it easily, then protection could be considered unnecessary.

 

[AntonLargiader]

Seems to me that in some situations zip-tying to the cold could also soak the Romex with condensation.

 

[Half-fast eddie]

I'm sure the thread title caught the attention of @PelicanPines

I’m disappointed. I expected to open the discussion and see some leather.

 

[acer66]

Seems to me that in some situations zip-tying to the cold could also soak the Romex with condensation.

That is what the outer plastic sheeting is for or is it against?

 

[mike93lx]

Seems to me that in some situations zip-tying to the cold could also soak the Romex with condensation.

Good point. THWN is better suited to be zip tied to the cold.



Hint, /s means sarcasm

 

[acer66]

Good point. THWN is better suited to be zip tied to the cold.



Hint, /s means sarcasm

Maybe I should have that as a sig line to get me outta dodge after posting nonsense once again.

 

[PelicanPines]

I’m disappointed. I expected to open the discussion and see some leather.

Sorry to disappoint... the convo went to Zip Ties... another favorite of mine... figured it was taking a good direction. Sometimes you just need to let your own imagination run with it. I can't be everywhere to satisfy your fantasies.

 

[sparky 1971]

Seems to me that in some situations zip-tying to the cold could also soak the Romex with condensation.

Good point. The whip should be UF.

 

[acer66]

Good point. The whip should be UF.

What about the condensation running down the whip into the heater?

 

[AntonLargiader]

That is what the outer plastic sheeting is for or is it against?

The outer jacket on NM is not waterproof. Neither is the conductor insulation. It will all soak water up and short internally (or externally to the pipe!).

Hint, /s means sarcasm

Got that on the cooling, but zip-tied NM is something that the sparkies here probably find all the time.

 

[sparky 1971]

What about the condensation running down the whip into the heater?

Haven't you ever heard of a drip loop? Rookies, can't live with 'em, not supposed to kill 'em.

 

[mike93lx]

The outer jacket on NM is not waterproof. Neither is the conductor insulation. It will all soak water up and short internally (or externally to the pipe!).

Got that on the cooling, but zip-tied NM is something that the sparkies here probably find all the time.

I insulate hot and cold, so condensation isn't an issue

 

[acer66]

Haven't you ever heard of a drip loop? Rookies, can't live with 'em, not supposed to kill 'em.

I knew should have kept my mouth shut.

 

[sparky 1971]

I insulate hot and cold, so condensation isn't an issue

Show off. Nobody likes it when someone brags about how deep their pockets are.

 

[mike93lx]

Show off. Nobody likes it when someone brags about how deep their pockets are.

Wait til you hear about all the insulation I have in my walls