Thru Wall PTAC Unit Closet Clearance (Need Help)

[CoolJames]

Hello,

We are in the process of finalizing the construction of a new maintenance building. There has been no problems with the design and the city has approved the permitting and the MEP design has been pretty thorough. Well to make a long story short. The electrical inspector came to perform his inspections and went through everything. There were no major issues found during the inspection, however when he got around to the closet HVAC unit which is a thru wall PTAC system he stated that the unit needed 3' clearance in front, because the unit has a integral switch that is inside of the unit. Now, I have never seen any inspector be so anal about something like this. Like I said the unit has an integral switch and the closet footprint was design per the manufacturers drawings. At this point the layout of the closet has been built by the contrator and the wall directly in front of the unit can not be modified, because it has stub up conduits through the concrete running up inside that wall. So, my question is, how can this matter be addressed and has anyone seen anything like this?

I have attached the manufacturers layout and the architect and mechanical team used this as a go by, but the inspector is making this into an maintenance and electrical issue. Now the layout that I have attached only shows the unit to have 12-inches in front however, the closet that has been built has approximately 18-19-inches in front of the unit. Also, to add the door on the side of the unit is 30-inches wide. The only way the unit can be service is if the unit is turned off, slid out and rotate 90-degrees and per the manufacturers the unit has to be removed off the wall in order to be serviced. In addition the 208V, 1phase service to the unit is being fed by panelboard that is within sight of the unit. The contractor also added an inline toggle switch as additional precautionary safety measures next to the unit inside the closet.

The only solution I can come up is to remove the inline toggle switch and install a 30A,2P non-fusible switch (blade type) on the outside of the closet and have that as the primary disconnecting and this will have more than enough clearance in front of the disconnect. However, there still is the integral disconnect switch inside of the unit and the inspector is saying that we would have to install terminal blocks inside of the unit and this derate the unit and we will have to get this unit relisted. At this point i'm lost for words with this inspector and we have offer a few options to rectify this and this guy won't let up. I think he couldn't return in the office empty handed, so he had to find something to justify he did his job.

Can anyone recommend a solution to this problem, so we can justify that the current configuration works as is or please share some insight if you have experienced such type installations.

Best Regards,
CoolJames :rant:

 

[George Stolz]

Talk to his boss.

 

[CoolJames]

Thru Wall PTAC Unit Closet Clearance (Need Help)

We did however, this guy is being resistant as well. We are running out of options. It's just a regular wall type (208V/1-Phase) unit and has to be slid out when servicing. The dang switch in internal to the unit and has a small pull switch to disconnect the unit. This guy is adamant on the clearance and we are running out of patience and options to proposed to him. Have you seen anything like this?

 

[CoolJames]

Thru Wall PTAC Unit Closet Clearance (Need Help)

Talk to his boss.

Thanks for the reply. We have reached out to his boss, however doesn't have all the info pertaining to the issue and is relying on the field inspector's opinion. So, with that being said he's being resistant as well. We are running out of patience and options to give these guys to get an option approved. Have you seen anything like this and if so, how was this rectified?

Thx,
CoolJames

 

[kwired]

Are you the installer or designer? Maybe a little of both?

If you are just the installer, get the designer involved.

Most thru wall units I have ever seen are cord and plug connected - if that is your case then the cord/plug is your disconnecting means, but sounds like that won't matter to this inspector as his concern seems to be narrowly minded toward access to something that is on the unit

Though it is outside the scope of what you are asking about, I am not getting the logic of putting this unit in a closet.

 

[petersonra]

It seems to me that IF the unit requires working space than it can't physically go where it was installed without violating the code.

The whole thing seems to hinge on whether it requires working space or not.

 

[James L]

Most thru wall units I have ever seen are cord and plug connected - if that is your case then the cord/plug is your disconnecting means, but sounds like that won't matter to this inspector as his concern seems to be narrowly minded toward access to something that is on the unit

Though it is outside the scope of what you are asking about, I am not getting the logic of putting this unit in a closet.

I agree here, especially cord-and-plug disconnect.

That said, every PTAC I've installed is cord-and-plug disconnect for a purpose - so that it can be pulled out of the sleeve, presumably for servicing as well as replacing.

Does removing it from the sleeve count as servicing?

And that closet install....wow

 

[CoolJames]

Thru Wall PTAC Unit Closet Clearance (Need Help)

My point exactly. We are the engineer and designer of the project. The closet footprint was built per the manufacturers documents as shown above and the panelboard that's feeding the unit is on the same wall within 10-12ft away located on the same wall. He's hung up on the clearance. For the closet design this type of PTAC has to be installed in a closet, because of the size of it and plus the client wanted a unit that could be hiding away from sight. The unit is larger than a typical wall thru and it has a supply duct on top that has to supply two other rooms which is very small in size. However this PTAC it's still consider a wall thru. It's sits on a sleeve where it has to pulled out anyway to be removed. Also, the manufacturer recommended 12-inches and we provided 18-inches. The integral disconnect is mounted inside the unit. I think this guy couldn't find anything else wrong with the design and couldn't go back to his boss empty handed. I think our best shot is to bypass the integral switch and connect the hot leads directly to L1 & L2 and have the contractor cover the switch and have the panelboard be used as the primary disconnecting means since it's within sight of the unit. What do you guys think about that or have you guys experienced anything like this?

Thanks,
CoolJames

 

[Dennis Alwon]

Where is the electr4ical inspector getting the 3" rule. That is not in the NEC...and why is he inspecting an HVAC issue? Secondly if the manufacturer has sent a note specify the layout then that should be good enough.

Is there a state inspector or engineer you can contact to cite your problem? Seems like you should be good

Sorry I read 3" instead of 3'-doh

 

[CoolJames]

To answer your question he's saying we need 36-inches in front of the integral disconnect thats mounted in the unit. I have no clue why this guy is inspecting this piece of HVAC so hard. NO IDEA about this guy! Check out the picture above and that is pulled directly from manufacturers documentation and the architect laid out the room per those drawings. In addition the architect gave the room more space that was on the manufacturers drawings. This guy is the city inspector and we are the engineer. We have been pleading our case to them, but they won't let up.

 

[petersonra]

To answer your question he's saying we need 36-inches in front of the integral disconnect thats mounted in the unit. I have no clue why this guy is inspecting this piece of HVAC so hard. NO IDEA about this guy! Check out the picture above and that is pulled directly from manufacturers documentation and the architect laid out the room per those drawings. In addition the architect gave the room more space that was on the manufacturers drawings. This guy is the city inspector and we are the engineer. We have been pleading our case to them, but they won't let up.

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.

110.26 Spaces About Electrical Equipment. Access and
working space shall be provided and maintained about all
electrical equipment to permit ready and safe operation and
maintenance of such equipment.
(A) Working Space. Working space for equipment operating
at 600 volts, nominal, or less to ground and likely to
require examination, adjustment, servicing, or maintenance
while energized shall comply with the dimensions of
II 0.26(A)( I), (A)(2), and (A)(3) or as required or permitted
elsewhere in this Code.

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.

 

[CoolJames]

I agree here, especially cord-and-plug disconnect.

That said, every PTAC I've installed is cord-and-plug disconnect for a purpose - so that it can be pulled out of the sleeve, presumably for servicing as well as replacing.

Does removing it from the sleeve count as servicing?

And that closet install....wow

Check out the manufacturers layout for the unit. slim vertical PTAC unit design for closets.

 

[K8MHZ]

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.

From the OP.

The only way the unit can be service is if the unit is turned off, slid out and rotate 90-degrees and per the manufacturers the unit has to be removed off the wall in order to be serviced.

 

[CoolJames]

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.

If thats the case then everyone will be in non-compliance with units like this one. Keep in mind the panelboard feeding the unit is right next to it within sight of no more than 10 ft apart. So, the circuit breaker in the panel will serve as the main disconnecting means up stream before you even get to the unit.

 

[kwired]

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.

And just what 110.26 should apply to has been debated here and many other places to no general consensus. Strictest reading of it means every junction box, machine, or other item that involves electrical energy would need to comply with 110.26. This would at least mean we would need a working platform next to every luminaire, air circulating equipment, and other components commonly found overhead in many places, or move those items to where they become impractical to use just so we can have 110.26 compliance.

 

[CoolJames]

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.

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?

 

[CoolJames]

And just what 110.26 should apply to has been debated here and many other places to no general consensus. Strictest reading of it means every junction box, machine, or other item that involves electrical energy would need to comply with 110.26. This would at least mean we would need a working platform next to every luminaire, air circulating equipment, and other components commonly found overhead in many places, or move those items to where they become impractical to use just so we can have 110.26 compliance.

My point exactly! This code is subject to interpretation.

 

[petersonra]

From the OP.

The only way the unit can be service is if the unit is turned off, slid out and rotate 90-degrees and per the manufacturers the unit has to be removed off the wall in order to be serviced.

Just to point out the obvious. The code does not seem to grant an allowance for removing it from the wall prior to service.

 

[petersonra]

And just what 110.26 should apply to has been debated here and many other places to no general consensus. Strictest reading of it means every junction box, machine, or other item that involves electrical energy would need to comply with 110.26. This would at least mean we would need a working platform next to every luminaire, air circulating equipment, and other components commonly found overhead in many places, or move those items to where they become impractical to use just so we can have 110.26 compliance.

there is no requirement found in the code to have ready access to such equipment. only that you have the required working space.

 

[petersonra]

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