Residential A/C Disconnect

[ICE]

Unless it is a repair and you use the IEBC....

Well I wouldn’t know anything about the electrical portion of the IEBC. I have yet to inspect an A/C repair.

 

[BuzzL]

BuzzL,
During my tenure as an inspector for LA County I did not require compliance with 110.26 if the A/C disconnect lacked an overcurrent device. The code was ambiguous enough that County policy allowed such an interpretation. This was a topic at the forum. The most vocal objector did everything short of call for a public flogging. Then the code was revised and the ambiguity was removed. We are now specifically instructed to require compliance with 110.26 with all A/C disconnecting means. There is no wiggle room. There is no bleeding into other ares such as a GFCI receptacle.

I do agree with you in that the code revision was poorly done. There is a need for working space if there is an overcurrent device. The code should properly make a distinction between a fused and non fused disconnect. Then Jeff could still be disappointed.

ICE - that is some great insight into the process. Thank you. Unfortunately, I agree - no wiggle room. Jeff will be happy for a while longer.

 

[Gregg Harris]

Gregg... what kind of disconnect are you using for your HVAC system? The non-fused disconnects that are commonly used do not expose electrical connections any more than a common receptacle does. Sure you can stick a paperclip in there and shock yourself, but it is simply a receptacle and plug. What "service" or "adjustment" is being conducted on a non-fused disconnect? Seriously... what service or adjustment is being done to a non-fused disconnect? As for your examples of a pencil and verbal resignation ... sure we can call them a device, but neither are "electrical" in nature. A receptacle (outlet) is electrical and nature and by the NEC's definition is a "device."

As for testing Amperage... that is typically done using wires inside the access panel to the unit. It is typically not done at the disconnect. It seems the bureaucrats that revised the 2023 NEC (in an effort to clarify) don't really understand how things work in the field. Other than using it to remove power to the AC unit, no one is messing around with an energized disconnect -- in other words AC disconnects are used exactly like a receptacle (outlet and plug). The whole discussion would make more sense if the workspace requirements were tied to the access panels on the AC unit, but that is not what the code says. It almost seems as though the bureaucrats are either confused over how HVAC units are serviced OR they are just trying to get more business for their companies.

I would suggest that most people on this forum (myself included) are doing okay financially and that the cost of moving a disconnect from one side of a unit to another during an HVAC replacement ($500 or so added onto the replacement cost) is a manageable expense; however, this is not the case for a lot of Americans. $500 is "real money" to a lot of our fellow citizens, and bureaucrats that want to assess that "fee" for dubious claims of safety really burn me up. Again... this is a whole different discussion if the work-space requirement were levied on the AC access panels where live conductors are routinely exposed during maintenance, but it isn't about workspace for the AC unit, it is about the electrical disconnect.

Work space requirements for the condensing unit also require 110.26 to be followed for the access panel that exposes the contactor, capacitor and circuit boards.

 

[klarenbeek]

Reviving this one because there were a couple differing views toward the end regarding clearance for the condensing unit itself:

Again... this is a whole different discussion if the work-space requirement were levied on the AC access panels where live conductors are routinely exposed during maintenance, but it isn't about workspace for the AC unit, it is about the electrical disconnect.

Work space requirements for the condensing unit also require 110.26 to be followed for the access panel that exposes the contactor, capacitor and circuit boards.

Compounding the problem is that if it is applied to the condenser itself (it would also apply to furnaces) is that the NEC requires 36" and the IMC/IFGC only requires 30". It gets even more confusing where inspectors are trade specific. As a mechanical inspector I pass it with 30" working space, then the electrical inspector fails it the next day because it doesn't have 36". Which code takes precedence???

 

[jar546]

Which code takes precedence???

The more restrictive always takes precedence. It is in chapter one of all the codes.

 

[klarenbeek]

Here's where we went with this after discussing with our CBO. NFPA 70/NEC is a referenced standard in IMC chapter 15. This is the IMC section regarding conflicts between codes/standards:

102.8 Referenced codes and standards.
The codes and standards referenced herein shall be those that are listed in Chapter 15 and such codes and standards shall be considered as part of the requirements of this code to the prescribed extent of each such reference and as further regulated in Sections 102.8.1 and 102.8.2.

Exception: Where enforcement of a code provision would violate the conditions of the listing of the equipment or appliance, the conditions of the listing and the manufacturer’s installation instructions shall apply.

[A]102.8.1 Conflicts.
Where conflicts occur between provisions of this code and the referenced standards, the provisions of this code shall apply.

[A]102.8.2 Provisions in referenced codes and standards.
Where the extent of the reference to a referenced code or standard includes subject matter that is within the scope of this code, the provisions of this code, as applicable, shall take precedence over the provisions in the referenced code or standard.

By his interpretation the IMC takes precedence when it comes to working space for listed appliances that the IMC regulates.

 

[steveray]

Here's where we went with this after discussing with our CBO. NFPA 70/NEC is a referenced standard in IMC chapter 15. This is the IMC section regarding conflicts between codes/standards:

102.8 Referenced codes and standards.
The codes and standards referenced herein shall be those that are listed in Chapter 15 and such codes and standards shall be considered as part of the requirements of this code to the prescribed extent of each such reference and as further regulated in Sections 102.8.1 and 102.8.2.

Exception: Where enforcement of a code provision would violate the conditions of the listing of the equipment or appliance, the conditions of the listing and the manufacturer’s installation instructions shall apply.

[A]102.8.1 Conflicts.
Where conflicts occur between provisions of this code and the referenced standards, the provisions of this code shall apply.

[A]102.8.2 Provisions in referenced codes and standards.
Where the extent of the reference to a referenced code or standard includes subject matter that is within the scope of this code, the provisions of this code, as applicable, shall take precedence over the provisions in the referenced code or standard.

By his interpretation the IMC takes precedence when it comes to working space for listed appliances that the IMC regulates.

You can do the same thing with the building code....Electrical guys hate that...Although in this case I would argue there is not a "conflict" and NEC110.26 prevails...

 

[jar546]

how do we get around 110.26(E)(2)(C) that requires “no piping or other equipment foreign to the electrical installation” in the dedicated equipment space?

You don't get around it. You comply.

 

[ICE]

By his interpretation the IMC takes precedence when it comes to working space for listed appliances that the IMC regulates.

By applying the NEC's more restrictive working space requirement there is no Listing violation of an appliance that has a lessor working space requirement. Had the NEC requirement been a lessor dimension rather than a greater dimension....that would be a listing violation.

 

[klarenbeek]

You don't get around it. You comply

The line set and condensate drain on the indoor air handler are not part of the electrical installation, yet they have to be in the working space because of where they connect to the unit. Same with bottom angle/unistrut of trapeze supports for hanging horizontal units. Literally has to be there.

By applying the NEC's more restrictive working space requirement there is no Listing violation of an appliance that has a lessor working space requirement. Had the NEC requirement been a lessor dimension rather than a greater dimension....that would be a listing violation.

It's not a conflict with the manufacturer's instructions, its a conflict between the IMC and the NEC. Because I enforce the IMC, I can't fail the mechanical contractor for not meeting NEC requirements. So the electrician ends up failing his inspection because the HVAC contractor met the 30" in the IMC but not the 36" in the NEC. I work with the electrical inspectors but don't enforce their code. We are trying to iron out how to handle this.

 

[Joe.B]

can't fail the mechanical contractor for not meeting NEC requirements.

Can't?

 

[wwhitney]

You don't get around it. You comply.

But it is worth noting that NEC 110.26(E) dedicated equipment space is entirely different from NEC 110.26(A) working space. 110.26(E) only applies (2017 NEC) to "switchboards, switchgear, panelboards, and motor control centers," while 110.26(A) working space applies to all equipment "likely to require examination, adjustment, servicing, or maintenance while energized." And if you do have a piece of equipment with 110.26(E) dedicated equipment space, that space is disjoint (non-overlapping) with the working space.

Cheers, Wayne

 

[jar546]

But it is worth noting that NEC 110.26(E) dedicated equipment space is entirely different from NEC 110.26(A) working space. 110.26(E) only applies (2017 NEC) to "switchboards, switchgear, panelboards, and motor control centers," while 110.26(A) working space applies to all equipment "likely to require examination, adjustment, servicing, or maintenance while energized." And if you do have a piece of equipment with 110.26(E) dedicated equipment space, that space is disjoint (non-overlapping) with the working space.

Cheers, Wayne

Understandable. The CMP has made this very clear over the years, and now it has been clarified in the NEC. Some did not enforce it in the past and with the clarification, some of those still won't enforce it. They are the ones that create issues of inconsistent enforcement.

 

[BuzzL]

But it is worth noting that NEC 110.26(E) dedicated equipment space is entirely different from NEC 110.26(A) working space. 110.26(E) only applies (2017 NEC) to "switchboards, switchgear, panelboards, and motor control centers," while 110.26(A) working space applies to all equipment "likely to require examination, adjustment, servicing, or maintenance while energized." And if you do have a piece of equipment with 110.26(E) dedicated equipment space, that space is disjoint (non-overlapping) with the working space.

Cheers, Wayne

Wayne - 2017 code didn’t invite this conflicting guidance, the 2023 code does. “Service Equipment” includes disconnect switches.

2023 Code Language:

110.26(E) Dedicated Equipment Space. All service equipment, switchboards, switchgear, panelboards, and motor control centers shall be located in dedicated spaces and protected from damage.

 

[wwhitney]

Wayne - 2017 code didn’t invite this conflicting guidance, the 2023 code does. “Service Equipment” includes disconnect switches.

Only if the disconnect switch is the service disconnect. I guess if the A/C unit is the only load on the service, then the A/C disconnect could be the service disconnect as well. Otherwise, 110.26(E) does not apply to an A/C disconnect.

Cheers, Wayne

 

[klarenbeek]

Can't?

Probably one of the very few downsides of trade specific inspectors instead of multi-hat inspectors. If I see a potential issue with one of the other trades, I'll suggest the contractor contact that inspector, I'll give that inspector a heads up, etc. I'll gladly work with them but I won't officially write up a violation of another trade's code. We had an inspector awhile back that had issues with that and was telling the GC there were issues with another trades work, where in fact there weren't any code violations. So no, I'm not going to fail something that's in a different trade's code.