(Non-garage) Help me wire my central AC

[Jefe]

Hi folks,
I'm an infrequent poster, but have gleaned a lot over the years from this forum, thanks for that!
As the post title says, I'm about to wire my AC's outdoor unit - breaker - wring, disconnect - whip.

I'm pretty knowledgeable with electrical systems, having wired my entire garage and most of my house by now. Just looking to make sure I use the proper gauge and type of wire and connections for this scenario.

here are the AC specs:

Power Conns. - V/PH/HZ: 208/230/1/60
Min Brach Cir. ampacity: 23
Br. Circuit Prot. RTG. - Max (amps):40​

Breaker panel is about 15 feet from where the disconnect will live, which is only about 1 foot from the AC unit.

What i need to verify:

- Breaker size
- Fused or non-fused disco (location: Columbus, OH - i don't think fused is needed)
- Wire gauge and type (can use NM in the basement until I get to to where it will exit the (brick) wall
- Conduit size for through wall to disconnect box
- Wire type/size in conduit (just continue with same NM cable? or other?)

Other considerations:
The nearest outlet will be 14' away, but on a deck, so might not pass for the required service outlet. Considering using one of the all in one AC disconnect boxes with outlet. If this is the case, how does this change wire and conduit choice? Do I just run a 12/2 cable in the same conduit for the outlet?

 

[matt_i]

With your min ampacity at 23 x 1.25 for motor loads puts you just inside of 30A so I would run #10 awg.

In my thinking a fused disconnect is overkill due to circuit breaker protection of conductors. However often there's an exterior "stab" disconnect to protect someone working outdoors from getting electrified by another person flipping circuit breaker handles inside the residence.

Personally I would use PVC conduit or plastic liquid tight conduit, aluminum j-boxes if possible. Powder coated steel would of course also work.

 

[Norcal]

10 AWG wire if NM cable, or 12 AWG THWN, 40A breaker either way is code compliant. With A/C equipment the above is permissible NM cable is sized to the sixty degree column of table 310.16 and art. 440 allows 12 AWG to be used at the rated 25A & the 125% calculations have already been done by the manufacturer. A disconnect is required I always use fusible but there are other ways as well.

 

[Jefe]

Thanks guys.
As for the exterior work, here's a picture of the location:

Note that the shaded area will be a deck.

Does that location for the disconnect make sense?
What's the best way to get from the indicated location on the wall to that disconnect?

What are you thoughts on using the all in one disco w/gfci outlets, like this?

thanks again!

 

[gregtwojeeps]

Your elec routing is fine, just strap it at the bottom of the disc within about 8 in. or so...

The disc/outlet combo is a good buy. If I see your proposed deck shading correctly, you are covering up your clean out for your gutter drop and access to the house point of entry for the A/C line set ....if it ever had to replaced if it got damaged. . Do you think that is a good idea to do ?

 

[Jefe]

The disc/outlet combo is a good buy. If I see your proposed deck shading correctly, you are covering up your clean out for your gutter drop and access to the house point of entry for the A/C line set ....if it ever had to replaced if it got damaged. . Do you think that is a good idea to do ?

Yes, it's an awkward area. I wish the line set was done differently but it's too late now. I'll end up notching the deck somehow to maintain as much access as I can.

As for getting the wiring there, what type of conduit and boxes should I be looking at? Liquid tight flex, or PVC?
What type of wiring should be in the conduit?

 

[CNGsaves]

^ ^ Build the deck with removable section so you'll still have access to clean-out and A/C lineset.

I'd also kill all that grass around the A/C unit and but down landscape fabric and cover with rock. You don't want to be weed whacking in around the A/C unit or that lineset line or the electrical feed.

 

[alfredeneuman]

The disconnect requires a working clearance of 36" deep and 30" wide. (NEC110-26)
The width measurement doesn't need to be centered on the disconnect. You can measure from either side.

It, as drawn above, doesn't appear that it meets that requirement.

 

[Jefe]

The disconnect requires a working clearance of 36" deep and 30" wide. (NEC110-26)

Well that would complicate things. Thanks for the heads up.

Anyone have an idea to satisfy that?

I could mount it to a temporary stake for now, then put it on the deck rim board later - on the left side of the deck in that photo. The downside is that it will require a feet of extra wire to get out and back.

 

[gregtwojeeps]

Where is the A/C getting its power from now ? I do not see it in your pic anywhere, just the copper line set. .

I could drive across my state right now and look at 2000 homes with the exterior A/C
( condensing unit) disconnect mounting location. I would bet the remainder of my years income that not 200 of them will meet the "required distance for servicing rule". JMO

 

[Jefe]

Where is the A/C getting its power from now ? I do not see it in your pic anywhere, just the copper line set. .

Um... as of now it has no power, hence this thread on how to wire it.

 

[gregtwojeeps]

Wait a minute, who sets an A/C unit, runs the charge lines and does not power it up ? I had better go read the OP again, sorry.

 

[Jefe]

Wait a minute, who sets an A/C unit, runs the charge lines and does not power it up ? I had better go read the OP again, sorry.

No worries! I guess I have myself to blame. Since I am doing other electrical work under my own permit, I just included the AC disconnect in my scope of work, and told the HVAC folks not to charge me for it, so they explicitly excluded the electrical work from their quote.

Now I'm behind schedule, it's 95 f@$%ing degrees, and my fiance is about to murder me in my sleep.

 

[gregtwojeeps]

No worries! I guess I have myself to blame. Since I am doing other electrical work under my own permit, I just included the AC disconnect in my scope of work, and told the HVAC folks not to charge me for it, so they explicitly excluded the electrical work from their quote.

Now I'm behind schedule, it's 95 f@$%ing degrees, and my fiance is about to murder me in my sleep.

O.K. I see now, I hope your sofa sleeps well...

 

[James-W]

Is there a way to run the power line behind the downspout? Or, perhaps going into the wall on the left side of the downspout?

 

[Jefe]

There is an inch or so behind the plastic portion of the downspout.
The wall to the left of the downspout is the corner of the house, so that's like 18" of solid brick - don't want to go through there.

 

[gregtwojeeps]

The proposed deck location is really complicating your project. Is there anyway to stop from building it all the way to the gutter drop ? Say back six inches from where the charge lines exit the brick.
( where the post is sitting) Is the wiring /copper lines coming out of a basement or crawl space ?

 

[Jefe]

The proposed deck location is really complicating your project. Is there anyway to stop from building it all the way to the gutter drop ? Say back six inches from where the charge lines exit the brick.
( where the post is sitting) Is the wiring /copper lines coming out of a basement or crawl space ?

I see where you're going with the question, but we can't really move it back. For one, it's only 14' wide, so i don't really want to give up any more space. But more importantly, just out of frame in the top of that photo are two windows and a door centered on that wall. We wanted the deck to encompass the entire wall, not end awkwardly near or under the leftmost window. In fact if we move it back, the railing might end up right under the window.

There is a basement.

 

[Stuff]

The disconnect requires a working clearance of 36" deep and 30" wide. (NEC110-26)

There is some debate about that applying as an a/c disconnect is not likely to be worked on when hot. Up to the local AHJ to determine.

 

[Jefe]

Right, i suppose a conscientious technician would flip the breaker in the basement then remove the disconnect handle to make sure he was safe in case someone flipped it back.
I'm thinking a call to the building official is in my future.

 

[gregtwojeeps]

O.K. On second thoughts. I really do not like the A/C disc being mounted on a fence post. Fences get blown over, have to be replaced ...on and on. Find a way to put the disc. on the brick wall to the right of the copper lines and mount it above the proposed deck floor height about 24 in.

The deck can be built to allow the conduit coming out of the basement and flex needed to clear it, just use some 6x 6 treated posts and have the deck band that would anchor to the brick... stand off the brick wall 1.5. inches. . A trim of sorts could be put around the conduit/flex on top of the deck to keep small animals/kids hand from getting down in the void.

Come thru the basement wall with 3/4 in. PVC and then stub it one inch passed the brick face. Seal the brick penetration well. Put a 3/4 in. PVC LB 90 degree fitting on it with the long side up.. Go out of the top of the LB with PVC in to the bottom of the disc. The 3/4 in. liquid tite flex coming out of the bottom of the disc will go to the A/C unit.

Strap the PVC conduits and flex properly. As long as the LB fitting is NOT behind the deck band and accessible by crawling under the deck, it will be o.k. Just my thoughts, this is a tuff project to figure from looking at a PC monitor. Some one will come along maybe and think of a better way . You don't need me to tell you this, but your eagerness to DIY...bit you. Good Luck. JMO

 

[Jefe]

I've thought of mounting the disco to the wall, and that is certainly more typical, but will this be an issue for the inspector since it's now on a different level, and separated by a guard rail from the condenser unit?

 

[gregtwojeeps]

Geez guy, just stop...call the inspector and have him or her...tell you how they want it done. This is too tough to figure via the internet. JMO

 

[Norcal]

Geez guy, just stop...call the inspector and have him or her...tell you how they want it done. This is too tough to figure via the internet. JMO

A inspector cannot tell you how to do it, or how they want it done, it just needs to comply with code.

Edit: For them to do so would or could make them liable, it's their job to inspect for code compliance, it's your job to do it right.

 

[Mustang51js]

Just do it the way you wanted in picture,pipe out,use an LB and pipe behind the gutter. Get your inspection and then put your deck up. If your worried about accessability space,just put the disco on fence to left of unit. I would do pvc to disco,then nonmetallic flex to the unit from disco. Run romex to a junction box on other side of wall. 3/4 inch pvc,10-2 rx with a 40 amp breaker,non fused disconnect. You will need some #10 thwn for wire in pvc

 

[6t7gto]

How will a tech get to the service points on the A/C unit when the deck and railing is in place?

 

[gregtwojeeps]

How will a tech get to the service points on the A/C unit when the deck and railing is in place?

In my replies yesterday I get that the OP's deck is his priority GTO, not his AC unit. He had a suggestion to set back the deck edge or to leave out a "notch" for access to the gutter drop clean out, and future access to the units line set going through the wall of the house. He wants as much deck with and sq. footage as he can get.

 

[Jefe]

Thanks everyone for the replies. No need to turn this into some kind of ******* match.
I know I have a unique situation (of my own doing). that's why I came here for insight, which several of you have provided.

Greg, thanks for coming back and adding detailed responses - it really does help.

Being my own GC is a learning process. In hind sight, I should have micro-managed the HVAC folks better - as 6t7GTO pointed out - they set the unit too close to the future deck. I'm going to see if they can move it.

 

[Jefe]

Update for everyone who participated:

I ran the wiring a few weeks ago, 10-2 and 12-2 down a joist to a metal box, transition to PVC conduit and THWN wire and out through the wall. Went ahead and mounted the combo disconnect / outlet box to the fence post and flexible whip to condenser.
Called the installer about the location and they were accommodating - the foreman on my job took the blame for the location. They sent a tech with some tubing and brazing equipment and he moved the unit over. All fired up and we're enjoying cool dry air!

 

[toyotadriver]

So....where are the pics??

Pics or it didn't happen!!!!