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I have a couple of reasons for posting this pic....but first, I thought I'd give everyone a crack at it!

- renosteinke
[Linked Image]

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Is that just regular PVC conduit that's been bent to shape?

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The 90 degree fitting at the unit suggests to me that is liquidtight flexible conduit not PVC.

I don't see any issues unless there is no outlet within 25'.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
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Is the thermostat wire in the sealtight? I can't see it.

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Cat Servant
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That is liquidtight, and not PVC.

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Do you know what's the story on all those drain lines (?) on the wall?

Mike (mamills)

Joined: Mar 2005
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There's no guard rail to that drop behind the far unit, [yet?]. I take it power and control circuit cables enter within the insulated refrigerant lines? Is it usual to put them both in the same insulating sleeve in the US? Freezing condense? Clearance side and rear looks ok, but I would have mounted the units higher for possible snow entry problems - I see some frost now. Bit exposed there to wind too.

And, is that a gremlin peering out from just below the 'liquidtight' in the foreground? [Linked Image]

grammar/spelling.

Alan



[This message has been edited by Trumpy (edited 03-24-2006).]


Wood work but can't!
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The liquidtight appears to encroach into the workspace for the disconnects.

(BTW), where's the control wire?

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Hopefully, 24V control wiring is not in disco too.

Adding that the sealtite could use better support and routed as not to be as likely to be stepped on.

[This message has been edited by NORCAL (edited 03-14-2006).]

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Isn't there a workspace violation for the disconnect on the unit further away in the picture? Like the unit is right in the way?

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Well, here's a pic of the disco open....I don't see any t-stat wire there!

- renosteinke
[Linked Image]

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John,
The cover over the refrigerant lines/ cable inlet on the nearer unit looks rather strange.
Maybe yours are different in the US?.

{Message edited to add missing word}

[This message has been edited by Trumpy (edited 03-15-2006).]

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The onlything i see is the Line / Load is backwords in the disconect.

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Cat Servant
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Ok, I suppose it's time for me to explain my purpose in posting these pics.

First, I'll answer some of the questions you asked.
The insulation over the "line set" (refrigerant lines) is simple closed-cell foam rubber. Sometimes, especially in industrial settings, this is then covered by a herder plastic shell. There is a company making a wiremold-like raceway for a really neat look, but I've never seen it used.

Every air conditioner (except for the smallest window units) has two basic assemblies. One is the "condenser;" that's what you see here. Inside the house, inside an air duct, is the other part- the "evaporator." In operation, the condenser gets hot, while the evaporator gets cold. This cold results in condensation on it- hence the litle drains you see poking out of the wall. They come from the evaporators.

Several of you noted that you could not see any thermostat wire. Good point; many times pics like mine will be shown, and it will be asserted that the low voltage t-stat wire must be in with the power wires, and thus a possible code violation.
My pic of the open disco shoots that theory down.
There are two other explanations for the "missing" t-stat wire. The first is that the HVAC guy ran it along with his line set, and it is buried under that foam rubber.
There is also another type of system that operates on the principle of pressure drop; when the inside needs cooling, the pressure in the refrigerant lines will drop- and that, in turn, will start the thing up.

The "moral" here is: You need to learn at least the basics of the other trades, to work with them effectively.

Oh, the violation? On this $1.5 million house, with over 100 receptcles....there is no receptacle fir servicing the equipment.

[This message has been edited by renosteinke (edited 03-15-2006).]

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So now I have to go to HVAC school? [Linked Image]
Who is the genius that put the condensors right under a bunch of windows. They should at least be closer together so they would be easier to screen with a fence or shrubs.

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Maybe I'm just being picky, but for a $1,500,000 house, the inside of that disconnect looks pretty darn slap-dash. They almost needed a wire-stretcher for that load-side conductor. [Linked Image]

-John

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The company I work for does about 250 of these A/C split-systems each year. I have become somewhat of an expert on wiring them. They are expected to be complete within' a 3.5 hour time frame, and they are for the most part always in older homes.

My personal opinion is this.

The disconnect is much too high. It needs only to be readily accessible. I like to keep them as close as possible to the condensor so I can get by using the bare minimum of 36" of LNFC without having to use a strap. This method also cuts down on the cost of THHN, and when you're doing 250 of them per year, well....

A GFCI receptacle that is required within' 25' of HVAC equipment is also missing. I usually look to change an existing receptacle (as long as it's on the same level as the equipment) and bring it up to date with a GFI and an in-use cover. That's not always a good idea when dealing with older homes because you never want to open a can of worms.

The A/C guys run the 18-2 from the condensor, to the air handler, 95% of the time. We install the 18-3 and the t-stat.

p.s. most attics are filthy dirty too [Linked Image]

[This message has been edited by ShockMe77 (edited 03-16-2006).]

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The two condensers are separated becaust they connect to two entirely different systems, located in different part of the house. One in the garagr (the near one), and one in the finished basement. This way, the referigerant lines are as short as possible.

Go to A/C school? That might be overkill..but an intro course or two at the community college wouldn't be a bad idea. If you think about it, there are a few more trades we all need to know something about.

[This message has been edited by renosteinke (edited 03-17-2006).]

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When I look at the disco picture, the cable coming in thru the back of the box looks like it is secured with an arlington 3/4" snap in connector, which is rated for up to 10-2. Now them line and load conductors appear to be #8 or #6. If I am not mistaken, the clearance for the disco extends clear to the ground, and the drain lines for the unit are entering that space and extend beyond the front of the disco. And drain lines are not associated electrical equipment to the disco, so therefore are not allowed out past the front of the box. Third, is there appears to be a little bit of snow on the ground, which means that the whole building was built in the wrong geographical location in the first place.

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Cat Servant
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Mac, those are some really good catches; I hadn't looked that close. Heck, I'm pleased they used any bushing at all!

I don't understand your comment about the snow, though. I assure you taht it sometimes gets warm in Nevada!

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Quote
What's wrong with this A/C install?

Nothing.


Peter
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One thing doesn't sit too well with me.
If you look at the nearer unit and how the Refrigeration pipes seem to just slope down to the unit.
I've installed a heap of A/C gear and a pipe run like that would not usually be done here.
Mainly because without any sort of mechanical relief, such as a bend or two, the sound from the unit (50-60Hz hum) will be transmitted to the wall.
I've seen this happen before over here.

[This message has been edited by Trumpy (edited 03-24-2006).]

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Ah Reno, I am just weather rubbing it in for all you winter guys. Actually it isn't all sunny here all the time. Right now we are pretty much under water so I should have not bragged.

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By renosteinke

Quote
On this $1.5 million house, with over 100 receptcles....there is no receptacle fir servicing the equipment

So what do I win?

Look at the second response to this thread.

By iwire
Quote
I don't see any issues unless there is no outlet within 25'

by renosteinke

Quote
The two condensers are separated because they connect to two entirely different systems, located in different part of the house. One in the garage (the near one), and one in the finished basement. This way, the refrigerant lines are as short as possible.

This is still no excuse, it is done simply to save money. The mechanical contractor could have grouped these units, they can run the lines as far as they are willing to pay for. Sometimes this means running larger diameter lines due to the distance just like we have to deal with voltage drop.

I also agree with shockme, I would have placed the disconnects much lower to hide them better, this is not the side of a factory its someones house.

Bob


Bob Badger
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I agree with ShockMe too... for $1,500,000 those discos could be a little lower. Other than perhaps electricians, they shouldn't be focal points like wall art.

But if they did have to be installed at that height for some reason (though what reason I'd love to know), at least go down the wall with pipe, then a short lenth of flex to the condenser. The way it is now looks very "DIYerish" though likely not a code violation.

Joe

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The problem here has been identified as the lack of outside gfi outlet by the OP. None of us could really tell that because we cant see around the corner to the right of the closest unit. Might have been a gfi right there and it looks like about 20 feet to the other compresssor to me.

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Cat Servant
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I didn't mean to be unfair, Mac. My main point with this thread was to show the need to know something about other trades.

Several times, I have seen pics like the first one in the trade press, followed by the assertion that, since there is no conduit for the T-stat wire, it must be in with the power conductors. It is then asserted that doing so is aviolation of the NEC- mixing of control and power circuits.

Without getting into a discussion of wheter the thermostst wire is a power limited circuit (to which that rule wuold apply), I wanted to show that the assumption behind those trade-press pics was wrong.

Indeed, some systems don't even have a control wire to the condenser.

We have to work with other trades all the time- and we can do that better if we have a basic understanding of their trade!

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Reno, I agree totaly with that. I work with AC contractors all the time as a sub, and love to ask about the workings of the big chillers, package units, and various other stuff installed. Some of it gets pretty complex and hard to understand. At least for me. They have an equally cool trade. No pun intended.

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From Alan Belson:

Quote
This is how I installed my A/c, on a pair of wrought-iron brackets made from old hand forged barn-door hinges, 2" x 3/8" section. This keeps them up off the deck in case of snow. There is no requirement in France for external disconnects. I ducted each 'split' through its own 2.5" PVC pipe, separate condense hose. French technician came today to 'gas up' and fit the copper exp/comp. tubes for me- can't do this gas myself, the pressure is too high [ R410A], special cone tools are required and the gas is 'weighed' in rather than pressure gauged. Eagle eyes may note he has has slightly dented the casing, LH front. Optical illusion, but the unit has 5" clearance at rear. The rocks are granite from Mrs B's "door mining" exploits, we put them there to stop our loony mail man-from crashing his van into the unit. Interior units are on 5/8" birch-ply mounts, as far as I've got with the sheetrock, all on Douglas Fir studs, 8" of glassfibre quilt to go in now.

[Linked Image]

[Linked Image]

[Linked Image]

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Looks like what we call here in the states a mini-split system. High voltage to the condensor, control wiring to the remote unit. I've done a few of those.

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300.3(C), FPN does not allow the thermostat wire in the supply.

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Welcome to the forum Barf.

Spaceballs Fan?

Quote
300.3(C), FPN does not allow the thermostat wire in the supply.

FPNs do not allow or prohibit anything.

FPNs are not code.

We could say 725.55(A) prohibits it but that is not entirely correct either.

There are ways to code compliantly run the the control circuit in the supply raceway.

But in general it is easer to keep them separate than to jump through the hoops needed to combine them.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
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Yes, I loved John Candy

Isn't the 725 rule enforceable though?

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The supply is via a dedicated A/C 25A breaker on the consumer unit, to a 2 pole 40A isolator C/W neon [oversize, but available to me ] direct to the outside unit. There are no 'thermostats' as such, all units have a microprocessor and use sensors to decide on rate of heat/cool as programmed from remote hand held 'blippers'. From the outside unit to each of the inside units are run 4-wire control cables, = 2 digital signal, 2 hot, twin ground wires, twin neutrals. The A/C runs with inverter technology - infinitely variable dc drives, ie. compressor soft starts and runs at optimum speed for maximum efficiency, all the time. You can hardly hear either inside or outside units and the minimum rated COP is 4.
Had it running today on heating while doing some sheetrock with Denise. 4kw of hot air for about 850W of juice from the poco.

Lovely! [Linked Image]

Alan

ps I should add that from the remotes I can ask for; temperatures on each zone, [cool or heat], plus: fan speeds, timed operations 24/24, direction of air by flap or by programmed swing, on-off, fans only, dehumidify, and filtration level, [ionify, zeolite, particle], or I can just specify a temperature and let the machine run itself on automatic. The processors handle the actual differentials.

[This message has been edited by Alan Belson (edited 04-10-2006).]


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