Thru Wall PTAC Unit Closet Clearance (Need Help)

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petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
you can get a pretty quick answer from the appropriate cmp if you formulate a question so it can be answered yes or no. it is not the same thing as a formal interpretation but it may well answer your question.
 

JFletcher

Senior Member
Location
Williamsburg, VA
CoolJames, some questions:

1) what is the model and mfg of the unit?
2) is it cord and plug or hardwired?
3) What code cycle are you on?
4) What code(s) is being cited, 110.26? What PTAC requires service while energized? Does punching in settings on the keypad constitute "service"?

If you cannot move the wall (which you stated you cannot) and the inspector doesnt give, can you build ductwork from the wall sleeve and rotate the unit 90* so that it faces the door, which would give you the 30" clearance?

I hope the thermostat is remote otherwise the unit will cycle itself to death in short order. it may very well freeze up anyway running in such a small space.
 

kwired

Electron manager
Location
NE Nebraska
there is no requirement found in the code to have ready access to such equipment. only that you have the required working space.
I never mentioned ready access, just a platform that allows the required working space, how to get to that platform wasn't mentioned either.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Bob,

His argument is that the switch located inside the unit behind the faceplate needs clearance of 3 feet. How ridiculous! Its a 208V,1-phase unit - two wire system. We are thinking to bypass the switch, connect straight to L1, LN to eliminate the switch and cover the switch opening since it's mounted flush inside the unit. What do you think of that option?


I think it is a good option and perhaps he will allow you to move the switch to a wall outside the unit. Is that switch accessible from inside the closet? Sounds like the unit needs to be pulled from the outside-correct? If so is the switch accessible that way?
 

kwired

Electron manager
Location
NE Nebraska
I think it is a good option and perhaps he will allow you to move the switch to a wall outside the unit. Is that switch accessible from inside the closet? Sounds like the unit needs to be pulled from the outside-correct? If so is the switch accessible that way?
But doesn't one need to pull the plug before pulling unit out anyway? IDK if we have verified this unit is cord and plug connected, but most are.

But that is sort of beside the point, this inspector seems to think the switch in question needs working space regardless of how many additional methods of disconnect may be present ahead of that switch. OP has offered to install additional disconnecting means but been shot down on those ideas IIRC as the inspector is focused on this one switch needing working clearance no matter what it takes.
 

James L

Senior Member
Location
Kansas Cty, Mo, USA
Occupation
Electrician
But doesn't one need to pull the plug before pulling unit out anyway? IDK if we have verified this unit is cord and plug connected, but most are....

I'm envisioning a j-box, or 2-pole breaker, or otherwise afixed to the inside of the sleeve, and the unit makes contact when it slides in....?

I've never seen one like that, just trying to wrap my brain around something that's not cord-and-plug
 

kwired

Electron manager
Location
NE Nebraska
I'm envisioning a j-box, or 2-pole breaker, or otherwise afixed to the inside of the sleeve, and the unit makes contact when it slides in....?

I've never seen one like that, just trying to wrap my brain around something that's not cord-and-plug

I understand.

Most units I've ever seen not only are cord and plug connected but also slide out toward the interior. Much easier to work on one on the 6th or even 80th floor when you pull it in instead of out.
 

James L

Senior Member
Location
Kansas Cty, Mo, USA
Occupation
Electrician
I understand.

Most units I've ever seen not only are cord and plug connected but also slide out toward the interior. Much easier to work on one on the 6th or even 80th floor when you pull it in instead of out.
Every unit I've ever seen is like you describe.

fwiw,
I just googled "hard wired ptac" and the results show a short flex with handy box on one end, sold as an "optional direct wire kit"

I wonder if this whole thing is as simple as instslling a factory cord back on the unit and plug it in
 

kwired

Electron manager
Location
NE Nebraska
Every unit I've ever seen is like you describe.

fwiw,
I just googled "hard wired ptac" and the results show a short flex with handy box on one end, sold as an "optional direct wire kit"

I wonder if this whole thing is as simple as instslling a factory cord back on the unit and plug it in

Most have little or no potential for live exposed parts until it has been pulled out of the wall as well, which you would think would be a consideration when determining if 110.26 needs to apply.
 

kwired

Electron manager
Location
NE Nebraska
there is no code requirement for a platform.

So if the item needing clearance is 30 feet off the floor, which might leave it accessible but not necessarily readily accessible, then if they want a free working space you about need some kind of platform to stand on don't you?

Or does NEC recognize that superman will be able to hover in front of this equipment, but still needs minimum of 30x36" of unobstructed space in front of such equipment?:cool:

I agree NEC doesn't specifically require a platform, but you need to have a way to get to the item regardless, and if you put a platform there then I would think it needs to allow for 110.26 clearances, a 12 x 18 inch surface might be something one can stand on but is not enough for 110.26.

How about a ladder rung in front of the area needing working space to stand on?

110.26 does cover height of work space as well. There is a lot of equipment in crawl spaces out there that doesn't comply with work space height requirements, question ultimately becomes what does need to comply? Likely to require service while energized - seems likely with a lot of HVAC equipment, yet a lot of what is installed never fully complies with 110.26.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
So if the item needing clearance is 30 feet off the floor, which might leave it accessible but not necessarily readily accessible, then if they want a free working space you about need some kind of platform to stand on don't you?

You may need some means of access, but the code does not require it WRT working space requirements.

Or does NEC recognize that superman will be able to hover in front of this equipment, but still needs minimum of 30x36" of unobstructed space in front of such equipment?:cool:

Again, the code does not require ready access. You can go up with a ladder and work on it as far as the code is concerned.

I agree NEC doesn't specifically require a platform, but you need to have a way to get to the item regardless, and if you put a platform there then I would think it needs to allow for 110.26 clearances, a 12 x 18 inch surface might be something one can stand on but is not enough for 110.26.

How about a ladder rung in front of the area needing working space to stand on?


I agree if you put a platform there it has to comply with the working space requirements.

110.26 does cover height of work space as well. There is a lot of equipment in crawl spaces out there that doesn't comply with work space height requirements, question ultimately becomes what does need to comply? Likely to require service while energized - seems likely with a lot of HVAC equipment, yet a lot of what is installed never fully complies with 110.26.
I also agree a lot of equipment is installed that does not meet the working space requirements. That does not mean such an install meets code. It still does not meet code, even if it gets a passing grade from an inspector.

I think you want the code to mean what you want it to mean and it just does not say that in the actual words of the code in this case.

There are a lot of installs out there that have cheated on one or more code requirements. Most times the kind of cheating that is done is not a safety or performance issue. It is just in violation of what is often a trivial code requirement. It is still a requirement.

There is another thread here claiming that allowing NM to be rained on means an inspector can red tag it just for that. yet the code provisions that would allow such a thing are pretty sketchy, while the code seems pretty clear about working space requirements.
 

CoolJames

Member
Location
Orlando, FL
@JFletcher

1) what is the model and mfg of the unit?
RESPONSE: Goodman manufacturing – model VTC – Small vertical packaged AC unit – thru wall

2) is it cord and plug or hardwired?
REPONSE: It can be both. Right now it’s hardwired, but we checked with the manufacturer and it can be plug in type.

3) What code cycle are you on?
RESPONSE: 2011

4) What code(s) is being cited, 110.26? What PTAC requires service while energized? Does punching in settings on the keypad constitute "service"?
RESPONSE: Yes, but now the Mechanical inspector is saying the same thing.

If you cannot move the wall (which you stated you cannot) and the inspector doesnt give, can you build ductwork from the wall sleeve and rotate the unit 90* so that it faces the door, which would give you the 30" clearance?
RESPONSE: No, because if rotate it then it won’t have enough clearance for the suction of air from the outside. That unit is designed exactly like the manufacturer recommended.

I hope the thermostat is remote otherwise the unit will cycle itself to death in short order. it may very well freeze up anyway running in such a small space.
 

CoolJames

Member
Location
Orlando, FL
I think you want the code to mean what you want it to mean and it just does not say that in the actual words of the code in this case.

There are a lot of installs out there that have cheated on one or more code requirements. Most times the kind of cheating that is done is not a safety or performance issue. It is just in violation of what is often a trivial code requirement. It is still a requirement.

There is another thread here claiming that allowing NM to be rained on means an inspector can red tag it just for that. yet the code provisions that would allow such a thing are pretty sketchy, while the code seems pretty clear about working space requirements.

The inspector is saying the unit needs 36-inches in front of the unit itself. It's a small packaged vertical thru wall unit mounted per the manufacturers drawings.
 

CoolJames

Member
Location
Orlando, FL
CoolJames, some questions:

1) what is the model and mfg of the unit?
2) is it cord and plug or hardwired?
3) What code cycle are you on?
4) What code(s) is being cited, 110.26? What PTAC requires service while energized? Does punching in settings on the keypad constitute "service"?

If you cannot move the wall (which you stated you cannot) and the inspector doesnt give, can you build ductwork from the wall sleeve and rotate the unit 90* so that it faces the door, which would give you the 30" clearance?

I hope the thermostat is remote otherwise the unit will cycle itself to death in short order. it may very well freeze up anyway running in such a small space.

JFletcher, I answered your questions down below. check them out.

1) what is the model and mfg of the unit?
RESPONSE: Goodman manufacturing – model VTC – Small vertical packaged AC unit – thru wall

2) is it cord and plug or hardwired?
REPONSE: It can be both. Right now it’s hardwired, but we checked with the manufacturer and it can be plug in type.

3) What code cycle are you on?
RESPONSE: 2011

4) What code(s) is being cited, 110.26? What PTAC requires service while energized? Does punching in settings on the keypad constitute "service"?
RESPONSE: Yes, but now the Mechanical inspector is saying the same thing.

If you cannot move the wall (which you stated you cannot) and the inspector doesnt give, can you build ductwork from the wall sleeve and rotate the unit 90* so that it faces the door, which would give you the 30" clearance?
RESPONSE: No, because if rotate it then it won’t have enough clearance for the suction of air from the outside. That unit is designed exactly like the manufacturer recommended.

I hope the thermostat is remote otherwise the unit will cycle itself to death in short order. it may very well freeze up anyway running in such a small space.
 

CoolJames

Member
Location
Orlando, FL
I think the guy might well be right in a very technical way. I don't much care what drawings or manufacturer's literature say. The key seems to be whether it needs the working space or not. I don't see how drawings or other documentation gets around that issue in any way.



Is it likely that the equipment will ever require adjustment, servicing, or maintenance while energized?

Having said that, a lot of residences have stuff that does not have the required working space.


Key word, ELECTRICAL EQUIPMENT. This is defined as an appliance and not a piece of electrical equipment. The switch is built inside the unit and all we are doing is providing power to it. that's it. The floor print was built accordingly to the manufacturers drawings.

No, Is it not likely that the equipment will ever require adjustment, servicing, or maintenance while energized? The manual even states that the first thing is to disconnect the power at the supply which is within sight of the unit.
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
Just to point out the obvious. The code does not seem to grant an allowance for removing it from the wall prior to service.

If the ONLY way the manufacturer allows you to pull maintenance on the unit is to TURN IT OFF and pull it out of the closet then it won't be "energized" and the rule wouldn't apply anyway, would it?
 

CoolJames

Member
Location
Orlando, FL
I think you are now suggesting that you want to modify a listed unit. I wonder what the inspector will think of that idea.

That was just a suggestion, but we definitely don't want to void the UL listing of the unit. We even offered to put a small manual disconnect that you can LOTO next to the closet and this guy still won't budge. This is mind boggiling!
 
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