# ac disconnect



## 480sparky (Sep 20, 2007)

Disconnect codes don't differentiate between resi, comm, or industrial.


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## MDShunk (Jan 7, 2007)

If you can see the panel from the equipment, and it's less than 50 feet, you don't need a separate disconnect. The HVAC guy is blowing smoke.

There are times where you need a disconnect on the unit, such as for fossil fuel burning appliances. Many of the mechanical codes require a disconnect that is operable while the flame is being observed.


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## RODDBODD (Feb 7, 2009)

that is what i thought. i have not bought a new code book so i just wanted to make sure it had not changed since my book.

thanks for the info!


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## KayJay (Jan 20, 2008)

RODDBODD said:


> we have ran power to 4 ac units inside a basement. they are all within 50 feet of the breaker panel. the ac guy says by code we have to have a disconnect at each unit. all i can find is "in sight" of unit.we do 99% industrial and control work so i am not sure about the code on this. this is a "buddy" job so i am trying to save him all i can.
> 
> thanks for any info!
> rodney


I would simply check with your local electrical inspector to avoid problems. 
Some inspectors may interpret 440.14 Location [2008 NEC] “within sight from and readily accessible from the equipment”, to mean accessible while standing at the equipment. Even with the definitions provided in Art. 100.


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## electricista (Jan 11, 2009)

KayJay said:


> I would simply check with your local electrical inspector to avoid problems.
> Some inspectors may interpret 440.14 Location [2008 NEC] “within sight from and readily accessible from the equipment”, to mean accessible while standing at the equipment. Even with the definitions provided in Art. 100.


I assume these are water source heat pumps since they are in the basement and not outside. Either way a resi disco is $10.00-- I would put one there just for comfort level however I agree with the others that one is not required.


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## manchestersparky (Mar 25, 2007)

Be sure to read the nameplate on the unit before doing anything!
I have seen units that state maximum FUSE size. If the unit only makes reference to a fuse and not a breaker the AHJ can require a fusible disconnect. 
If it says maximum fuse/HACR Breaker then it could be either.


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## electricista (Jan 11, 2009)

manchestersparky said:


> Be sure to read the nameplate on the unit before doing anything!
> I have seen units that state maximum FUSE size. If the unit only makes reference to a fuse and not a breaker the AHJ can require a fusible disconnect.
> If it says maximum fuse/HACR Breaker then it could be either.


Not questioning you but I have not seen a unit that says max fuse in years and those were old units. Do you see these on commercial or resi installs?


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## manchestersparky (Mar 25, 2007)

They were on a commercial rooftop. I agree they are few and far apart. Just throwing it out there as no everyone bothers to pay attention to the entire nameplate. They only see overcurrent ratings


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## volty (Jan 14, 2009)

KayJay said:


> I would simply check with your local electrical inspector to avoid problems.
> Some inspectors may interpret 440.14 Location [2008 NEC] “within sight from and readily accessible from the equipment”, to mean accessible while standing at the equipment. Even with the definitions provided in Art. 100.


I think KayJay has a good point with the first sentance of 440.14. The panelboard breakers are already readily accessible by 240, so when 440.14 requires the ac disconnect to be " . . . within sight from *and* readily accessible *from* the air-conditioning or refrigeration equipment.", the intent may be to have it at the equipment.
Hmmmm.


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## unionwirewoman (Sep 7, 2008)

Although I'm still an apprentice , I have a degree in HVAC , and worked in that field for five years ( service and install ) . If it was a changeout , we always installed a fused disconnect , even if the panel was in sight . Not sure what the code reads ( every inspector reads it differently ) but I think the purpose of the fused disconnect is for service calls , and also for the protection of the circuit boards that 99% of the new units have . I would install them personally , unless you want your friend paying extra money for an over the weekend ot call . Trouble shooting some of the new units can be a little tricky .JMO.


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## electricista (Jan 11, 2009)

I cannot understand why an inspector would call for a disco to be place next to the unit when, IMO, it is clearly stated that a disco must be within site and readily accessible. Readily accessible simply means you don't need ladders or need to climb over things to get to the disconnect. 


> Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections *without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, and so forth.*


Within site is also clear.


> In Sight From (Within Sight From, Within Sight). Where this Code specifies that one equipment shall be “in sight from,” “within sight from,” or “within sight of,” and so forth, another equipment, *the specified equipment is to be visible and not more than 15 m (50 ft) distant from the other*.


A breaker 50 feet away, within site and not hindered by obstacles is readily accessible. If they wanted the disco next to the unit then it should state within 5' of the unit, or something of that nature.


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## JohnJ0906 (Jan 22, 2007)

electricista said:


> I cannot understand why an inspector would call for a disco to be place next to the unit when, IMO, it is clearly stated that a disco must be within site and readily accessible. Readily accessible simply means you don't need ladders or need to climb over things to get to the disconnect.
> 
> 
> Within site is also clear.
> ...


I agree. Just because you have to walk to the panel doesn't mean it isn't readily accessible.


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## volty (Jan 14, 2009)

While I want to agree with the two previous and reasonable posts, why does the NEC bother to say "readily accessible *from"* the equipment?

This is something I haven't looked at this way before, but . . .


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## MDShunk (Jan 7, 2007)

volty said:


> While I want to agree with the two previous and reasonable posts, why does the NEC bother to say "readily accessible *from"* the equipment?


Probably when they put that word in there 50 years ago, they didn't really think people would be dissecting it word-by-word in times to come. Can you see the disconnect from the equipment? _Check._ Is the disconnect 50 feet or less from the equipment? _ Check._ Can you readily access the disconnect? _Check._ Three checks... you're compliant.


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## electricista (Jan 11, 2009)

volty said:


> While I want to agree with the two previous and reasonable posts, why does the NEC bother to say "readily accessible *from"* the equipment?
> 
> This is something I haven't looked at this way before, but . . .


The readily accessible is still an important part of the article. A disco can be within sight and 50 feet but not readily accessible thus the need for the term.


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## jwelectric (Sep 28, 2008)

electricista said:


> The readily accessible is still an important part of the article. A disco can be within sight and 50 feet but not readily accessible thus the need for the term.


Or the disconnect my by readily accessible and not within 50 *FROM* the equipment


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## brian john (Mar 11, 2007)

I thought the intent was for the safety of the service tech. So the HVAC units meet the intent of the code and the servicing tech can safely work on the units, seems to me to be acceptable.

Though in some areas some inspectors have different ideas writing their own code as they go along so as noted I would check with the AHJ.

But Rodd, to be an electrician and not have the most recent copy of the NEC is IMO sinful, it lowers you in the field from an electrician to??????????


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## RODDBODD (Feb 7, 2009)

i know the code as it pertains to what we do. we install 400 to 10000 amp power systems and do plc and all other types of control work, dc magnetics, and other industrial maintenence. we do no commercial type work. this is the reason i posted the question. i think since we have been in business for 39 years, we probably are considered to be electricians.


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## brian john (Mar 11, 2007)

RODDBODD said:


> i know the code as it pertains to what we do. we install 400 to 10000 amp power systems and do plc and all other types of control work, dc magnetics, and other industrial maintenence. we do no commercial type work. this is the reason i posted the question. i think since we have been in business for 39 years, we probably are considered to be electricians.


Look many on here are code experts way beyond anything I know, and I bet they bought an NEC as soon as it hit the shelves. Me I know what I know but still keep a NEC handy. The 2008 has been out for a year and is pretty much available everywhere from a supply house to Amazon and Ebay.

This is just my opinion you are free to do as you like, I just do not understand an electrician not owning a copy of the current NEC.


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## electricista (Jan 11, 2009)

brian john said:


> Look many on here are code experts way beyond anything I know, and I bet they bought an NEC as soon as it hit the shelves. Me I know what I know but still keep a NEC handy. The 2008 has been out for a year and is pretty much available everywhere from a supply house to Amazon and Ebay.
> 
> This is just my opinion you are free to do as you like, I just do not understand an electrician not owning a copy of the current NEC.


Most electricians I know own a copy but don't read it till they get nailed on something. I was doing that myself for years-- just picking up the new stuff year by year--


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## volty (Jan 14, 2009)

MDShunk said:


> Probably when they put that word in there 50 years ago, they didn't really think people would be dissecting it word-by-word in times to come. Can you see the disconnect from the equipment? _Check._ Is the disconnect 50 feet or less from the equipment? _Check._ Can you readily access the disconnect? _Check._ Three checks... you're compliant.


When Art. 440 came out in 1971 it had sections about the disconnecting means, but not about the location (that I could find in a quick reading). In 1975 Section 440-14 appeared, with the language "readily accessible *from* the air-conditioning or refrigerating equipment."

Other wording for disconnects or OC protection that year used "in sight from" or "in sight of": 424-19(a)(1) and (d), 430-102, 430-106.

or "readily accessible" or "readily accessible to the user": 230-72(c), 240-24(a), 422-21(b), 422-23(c), 430-107.

No where else does the NEC seem to use the phrase "readily accessible *from"*, that I have ever seen. They do choose the wording carefully, why is it written this way? :blink:


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## 480sparky (Sep 20, 2007)

volty said:


> .........No where else does the NEC seem to use the phrase "readily accessible *from"*, that I have ever seen. They do choose the wording carefully, why is it written this way? :blink:


"Readily accessible from" also appears in 517.72(B), 520.21, 610.32, 620.24, and 660.5.

There are a total of 32 sentences in the '08 that contain the words _readily,_ _accessible_ and _from,_ but those 5 above contain that exact phrase.


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## volty (Jan 14, 2009)

I love the age we are living in! Instant info!:thumbup:
I'll peruse a few of those. Thanks.


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## 480sparky (Sep 20, 2007)

volty said:


> I love the age we are living in! Instant info!:thumbup:
> I'll peruse a few of those. Thanks.


NEC CDs are just the cat's meow!


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## volty (Jan 14, 2009)

*Thanks 480*



480sparky said:


> "Readily accessible from" also appears in 517.72(B), 520.21, 610.32, 620.24, and 660.5.
> 
> There are a total of 32 sentences in the '08 that contain the words _readily,_ _accessible_ and _from,_ but those 5 above contain that exact phrase.


440.14 Disconnecting means shall be located within sight from and readily accessible from the air-conditioning or refrigerating equipment. . .
517.72 (B) The disconnecting means shall be operable from a location readily accessible from the X-ray control.
520.21 -Typo?
610.32 . . . Where the disconnecting means is not readily accessible from the crane or monorail hoist operating station, means shall be provided at the operating station to open the power circuit to all motors of the crane or monorail hoist.
620.24(B) The lighting switch shall be so located as to be readily accessible from the pit access door.
660.5 . . . The disconnecting means shall be operable from a location readily accessible from the X-ray control. . .

Seems like for 610.32 at least the intent is clear, be able to disconnect power from the point of operation.
For the X-ray sections the intent may be the same, but may not be as absolute.
I feel that the 440.14 intent may be similar, but still am not sure.:no::yes:


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## 480sparky (Sep 20, 2007)

volty said:


> ..........520.21 -Typo?.....










10-key!

520.51.


> 520.51 Supply.
> Portable switchboards shall be supplied only from power outlets of sufficient voltage and ampere rating. Such power outlets shall include only externally operable, enclosed fused switches or circuit breakers mounted on stage or at the permanent switchboard in locations *readily accessible from* the stage floor. Provisions for connection of an equipment grounding conductor shall be provided. The neutral conductor of feeders supplying solid-state, 3-phase, 4-wire dimmer systems shall be considered a current-carrying conductor.


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## brian john (Mar 11, 2007)

electricista said:


> Most electricians I know own a copy but don't read it till they get nailed on something. I was doing that myself for years-- just picking up the new stuff year by year--


 
I have always done the opposite I review my NEC when ever I start something I have not worked on or around before. I hate being red tagged and can truly say in 38 years I can only think of two cases and IMO even then it was questionable.


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## volty (Jan 14, 2009)

I think with 520.51 in the mix, I am on the side of "accessible *from*" meaning As Close As Possible, if not Right There. The intent is surely to allow disconnection ASAP by those working with the equipment, be it X-ray techs, stage hands, material operators, or hvac techs.

Sometimes - after realizing there is a problem - leaving the chair, exiting the control room with a window, moving a gaggle of doctors aside in a hall, running 49 feet and flipping a breaker might take too long when the X-ray apparatus can't be turned off for some reason.

I think "accessible from" means able to be accessed from that spot or area.


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## KayJay (Jan 20, 2008)

volty said:


> I think "accessible from" means able to be accessed from that spot or area.


The commentary in the 2008 Handbook for 440.14 seems to support your interpretation.


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## JohnJ0906 (Jan 22, 2007)

volty said:


> The intent is surely to allow disconnection ASAP by those working with the equipment, be it X-ray techs, stage hands, material operators, or hvac techs.


Disconnects for the servicing of equipment are not emergency switches. They are for disconnecting power so the equipment can be worked on safely.


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## volty (Jan 14, 2009)

JohnJ0906 said:


> Disconnects for the servicing of equipment are not emergency switches. They are for disconnecting power so the equipment can be worked on safely.


Agreed, but the hoist operator or service tech or roadie (or others) may cause a situation while working that would require the power to be disconnected really quickly. So that may be why the NEC adds the word "from" to "readily accessible" these few times.

Or my favorite reason for placing a disconnect near, so it actually gets used. I may be able (per 422.30(B)) to place a lockout hasp on a remote breaker for a dishwasher, but if a snap switch exists in the adjacent cabinet, it will IMO get used more times during some repair troubleshooting than one far away. Just 'cause it's easier than walking downstairs again. And again . . .


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## electricista (Jan 11, 2009)

volty said:


> Agreed, but *the hoist operator or service tech or roadie (or others) may cause a situation while working that would require the power to be disconnected really quickly*. So that may be why the NEC adds the word "from" to "readily accessible" these few times.
> 
> Or my favorite reason for placing a disconnect near, so it actually gets used. I may be able (per 422.30(B)) to place a lockout hasp on a remote breaker for a dishwasher, but if a snap switch exists in the adjacent cabinet, it will IMO get used more times during some repair troubleshooting than one far away. Just 'cause it's easier than walking downstairs again. And again . . .


Volty there is nothing wrong with you wanting the a/c disconnect next to the unit but, IMO, there is no wording to support it.

Your statement in bold above can apply to any circuit in the house. Suppose the refrigerator starts smoking-- yeah we are not going to pull it out and unplug it but you will have to get to the panel and it's not in sight in most cases. The disco for an a/c is for the service tech to use to safely work on the unit. They want it in sight so that they can see if someone may turn it on. The disconnect for the a/c is not for emergency use.


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## seo (Oct 28, 2008)

brian john said:


> I have always done the opposite I review my NEC when ever I start something I have not worked on or around before. I hate being red tagged and can truly say in 38 years I can only think of two cases and IMO even then it was questionable.


Thats a very good point Brian I wish everyone would take a look at their NEC when they start a project and reference the code section pertaining to the job.


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## randomkiller (Sep 28, 2007)

For what it's worth, regardless if the panel is within site or not we always install a service disconnect on the equipment, sometimes this is just a basic two pole switch..


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## bobelectric (Feb 24, 2007)

I always buy the newest N.E.C. code book. Pa. still under 2005 code.


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## fishtape (Jul 11, 2008)

We used to go by the 50 ft rule or eyesite & got tagged before for not having a disc w/i 6' of unit. They told me it is a mechanical code????????
This was mainly for package units


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## volty (Jan 14, 2009)

electricista said:


> Volty there is nothing wrong with you wanting the a/c disconnect next to the unit but, IMO, there is no wording to support it.


Well I never . . . 
felt this way before this thread, that is!

Looking at each of the six sections referenced in post #26, including this one (440.14), use the wording "readily accessible from". Only these six in the whole book.

I included hoist operator, tech and roadie because they are some of the likely subjects of the sections referenced. The dishwasher comment is an aside, just a secondary possibility. I think they (NFPA) probably use the word "from" to have the disconnect extremely accessible, right at that location, for those few applications. Why do you think they say "from"?


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## KayJay (Jan 20, 2008)

volty said:


> Well I never . . . felt this way before this thread, that is!
> quote]
> 
> IMO, it appears that the CMP has taken into account the need for AC/R equipment to often be energized and de-energized during routine maintenance and the troubleshooting process. A technician often needs to install, reposition and remove jumpers, test leads, Tattletales, pressure gauges, gauge manifolds and hoses, temperature probes, as well as open and close valves in addition to making other adjustments.
> ...


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