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Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Posted by akrauss (My Page) on
Wed, May 13, 09 at 12:59

Can anyone give me an approximate cost for suitable wire (copper or aluminum ?)for a 200 foot run from a pool heat pump to my panel ? Dont know what my town code requires yet. About 3/4 of the run will be buried with the remainder tacked under my deck. Heat pump will require either 40 amp or 50 amp dedicated circuit. Thanks.


Follow-Up Postings:

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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

You have to use #8 THWN (or some similar wet rated conductors) (at least for the underground part) times three.
You'll have to continue the conduit or make a transition to some appropriate cable under the deck.

I assume that this is 240V and the actual load is somewhere around 32A, so the voltage drop won't be too unreasonable.

Call up your local supply house and ask how much 600' of THWN will cost. Prices vary with time and location.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Thanks ronnatile. I believe it is 220 volt. Silly question -why do I need 200 feet times 3 or 600 total feet ? Is it positive, negative and ground ?


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Well GROUND and two current carrying conductors. Not proper to call AC positive and negative, but you got the idea.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

It's 240V (although some folks still call it "220").

U.S. residential wiring is "split phase", coming from opposite poles of the power company's transformer. If you wire something to each of two poles, you get 240 volts. If you wire it to only one of the poles, along with a neutral (which goes to the center core of the transformer), you get half of the potential, or 120 volts.

Because it is "alternating current", the terms positive and negative don't really apply. (It alternates!)

So, for a 240V circuit that does not also feed anything needing 120V, you need two "hot wires" plus ground. (If the equipment you're feeding also needs 120V, you'll need four wires--two hots, a neutral and a ground.)

I'd agree with Ron, BTW, that the most economical solution is to buy spooled THWN. It's worth noting that with a single spool, you only get one wire color (typically black). While many locations will allow you to use a single color for the two hot wires (as long as it's properly marked), the ground needs to be green.

So, the likely situation is that you'll need 400 feet of #8 for the two hots and 200 feet of green-insulated (or possibly bare) wire for the ground. The ground wire, BTW, can be sized slightly smaller at #10AWG.

So...if I were pricing this, I'd ask for 400' of #8AWG current-carrying (black) conductors and 200' of #10 green insulated ground. That can affect pricing in terms of how it relates to spool size. (200' and 500' are fairly common off-the-shelf spool sizes and a single 600' spool doesn't do you much good.)

I'd also check prices on #6 size wire since, although Ron's guestimate seems in the ballpark to me, you'll need to verify the faceplate demands of the heat pump. If it draws much more than his estimate, it might bump you up to #6 wire, especially with a run that length, where voltage drop becomes a borderline issue.

The wire is much more expensive than the conduit, but if you want to price that, 1 1/2" PVC would be a good starting point even if you could go a size smaller. (The larger the conduit, the easier to pull and it isn't that pricey.)


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Thanks to all for this quick crash course in electrical. I have attached a link to the spec sheet for the heat pump. I am interested in the DX5HP. terribletom - you got my heart palpitating since I didnt even think about conduit. Silly me, I figured it was just direct burial. I know, probably not the smartest idea even if allowed. Can you please venture a guess at cost for wire and conduit as suggested. I will not hold you to it. Thanks again !

Here is a link that might be useful: Heat Pump Electrical Info.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Pool wiring almost invariably has to be in conduit, rather than buried cable. But, please, calm down on those palpitations because THWN in conduit isn't appreciably more expensive than UF cable. And if you're looking for a silver lining here, your minimum trench depth is only 18" for conduit versus 24" for direct buried cable. So, when you factor that in, it's probably a "push" or better.

I glanced at your link, and a second page with (partial) installation specs, and note that your model requires a 50A dedicated breaker. (This should be a GFCI breaker, BTW.) The manufacturer states that "breaker sizes are determined based on maximum circuit ampacity and rounded up to the nearest standard size", so the actual draw can't be determined more precisely from those materials.

Based on that spec and the length-of-run info you provided, I'd use #6AWG wire rather than #8AWG in this case.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

I dodged your price question because I haven't bought enough THHN/THWN in the past year or two to have a good sense of the current retail market. (Anything made with copper has been pretty volatile in recent years and, not surprisingly, it's gone up more often than it's gone down.)

If I were a contestant on "The Price is Right", I'd guess that you can find a 500' spool of #6AWG THHN/THWN copper for somewhere in the neighborhood of $400-500 and 200' of #10 for around a hundred bucks--so maybe $500 or so for the wire. Figure a buck a foot or less for 1 1/2" Schedule 40 conduit.

(Obviously, I've left out fittings, glue, circuit breakers, lubricant and pilot rope for pulling the wires, and a few other assorted goodies which are tough to estimate without knowing more about the particulars. And I haven't built in any markup, which a contractor is likely to add.)

The big missing item, of course, is labor. (You haven't mentioned whether this is a DIY project or not.)

BTW, if one the sparkies here who buys this stuff regularly weighs in, use their guestimates over mine! I'm just shooting from the hip and aiming for the side of the barn.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Were talking about pool equipment here so there are some additional things we need to take into consideration. Since it is an electrical pool heater rated at 50 amps you will be required to use #6 THWN minimum for the conductors. The ground must be insulated as well.

It is really hard to give prices on THWN, anytime I give an estimate I always call to verify pricing and right now I am being told that copper is going back up. That being said #6 for a 500' roll *should* be around $.70/foot - however location and time can make this vary significantly. Just call a local electrical supply house and ask them what #6 THWN is per foot.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump 1

I just re-read the original post and am concerened. Are you planning on installing this unit yourself? At first I thought you mentioned an electrician but after re-reading it I have the impression it is a DIY.

Pools are really not a place to mess around as a DIY, especially when it comes to something like this. Just an example - do you know how to properly bond this unit to the pools existing bonding system?

Based upon the comment of "tacking" the wire up under the deck (which is a violation on many levels) I am going to recommend that you call an electrician.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

The unit is not RATED at 50A. It requires a 50A branch circuit. I suspect it only draws about 32A which is what I used for my voltage drop. #8 wire is sufficient if you're using Copper THWN (and you're not stuffing it in a conduit with other stuff to the point of requiring derating).

Whether the heater itself qualifies under the 680.21(A) requirement for a insulated ground is perhaps a local interpretation thing. My argument is it is not strictly required by the code (though not a bad idea).

Note that the heat pump also is required to be connected to the rest of the pool bonding system by SOLID 8 AWG wire, so make sure you add enough of this to your shopping list.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Ya know, Ron, you may be right on the basis of your personal knowledge of that equipment. The thing that's frustrating about those online installation instructions is that I can't find anything that gives the minimum circuit amps (MCA) for the unit. They say to look on the nameplate for the rating, but how are you supposed to size this thing in advance when all you have to work with is a breaker size that's based on rounding up the maximum circuit size? It stands to reason that 5hp isn't going to eat up 40+ amps except during startup surges.

While the solid #8 bonding conductor may be required for bonding to the local earthing electrode(s), I'd argue that that wire is sized to handle lightening strikes rather than trip the OCPD. So, I still believe that the equipment grounding conductor used for the 200' run can be based on Table 250-122 which, if I'm reading it right, would be a #10.

I might be wrong about this but, if so, I'd like to hear the arguments.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

While the solid #8 bonding conductor may be required for bonding to the local earthing electrode(s), I'd argue that that wire is sized to handle lightening strikes rather than trip the OCPD. So, I still believe that the equipment grounding conductor used for the 200' run can be based on Table 250-122 which, if I'm reading it right, would be a #10.

It's got nothing to do with the local earthing electrode. It has everything to do with bonding the exposed metal, equipment, and other related parts of a swimming pool together. See Article 680.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Ron, I think we'd both agree that the #8 solid refers only to the equipotential bonding grid.

"It's got nothing to do with the local earthing electrode."

There's where I believe we may disagree. Ultimately, I believe the connection to the earthing electrode has to be "sized for the largest grounding electrode conductor required among all the electrodes connected to it." 250.64(F)

As for the application of Article 680, I'm using the link supplied below for the following:

680.26 Bonding.

(A) Performance. Bonding as required by this section is intended to help reduce or eliminate voltage gradients in the pool area by forming a common bonding grid. Bonding is not required to provide a low-impedance ground-fault current path.

FPN: The bonding requirements contained in this section are not intended to require an 8 AWG copper conductor to be bonded to a panelboard, service equipment or electrode.

I may be interpreting this incorrectly, but to me it seems consistant with the interpretation that the #8 requirement for the bonding grid has nothing to do with the equipment ground requirements for the feeder run.

Here is a link that might be useful: Re: Article 680


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

If I may interject - - I certainly appreciate the extensive thought and input provided by all of you. I am also glad to see I sparked an academic debate. However, at this point all I want to respond to is the suggestion that I might be tackling the electrical on my own. To be clear... the answer is a resounding NO ! The only task I was considering doing on my own was the digging of the trench. Regardless, I will certainly pass on all of your points to the electrician of my choice.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Hey, akrauss! Good to see you back and sorry if I've strayed too far from your problem in the process of getting schooled by Ron!

Doing your own trenching sounds like a great idea to keep down $$$ and I'm glad to hear you'll be using an electrician for the rest of it.

Good luck with this project.

Ron: Upon re-reading some stuff, I think my reference to 250.64(F) is misplaced. Sorry 'bout that.

But back to the more practical question regarding this OP. Do we agree that the #8 grid requirement is independent of the sizing of the equipment ground, or are you saying that the EG has to be #8?


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

No, I was telling him in addition to buying the wire for running the power back to the panel, he also needs to price out enough #8 solid wire to connect his heat pump to the rest of the pool bonding grid. That could be anywhere from a few feet to quite some distance depending on where the heat pump is situated and how far the nearest thing that's convenient to hook to is.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Gotcha. Capisce and thanks, Ron.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

OK- I have to show my ignorance: Can you explain what a "pool bonding grid" is ? Is that just a way of saying that the heat pump needs to be tied into the grounding system for the other pool equip., which in my case is just the water pump ? Thanks again.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

All the exposed metal (pool ladders, etc...), the rebar in the concrete, the pumps, and other pool equipment is required to be BONDED together with #8 solid wire. This is to make sure that if for some reason something becomes energized, that everything is at the same potential which is the safest. You'll typically see a terminal on the heaters and the pumps made for pools to provide for this and then it runs off to the other structural metal.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Understood. Thanks.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

I wonder if the OP would be able to use aluminium wire with the appropriate fittings and paste?

I know there are lots of people dead against it, but lots of service and transmission wire is aluminium, and it's commonly used here in Canada, especially between panel and sub-panel. I assume the paste is a permanent solution.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

He certainly CAN NOT use aluminum for the bonding wire.
He could use aluminum, with fittings listed for it. However, it's not real common in the US to find aluminum in the sizes he's talking about. You don't tend to see it until you get up in the order of #2.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Aluminum wire is fine when it is large enough to be stranded.

Solid aluminum wire (#14-#10) tried to balance the low temper of the wire needed for flexibility with the higher temper needed to not distort under screw pressure at devices.

Needless to say, it is a balance that cannot be met.
The solid aluminum wire used in the 1970s did not have enough temper for use under screws, and normal thermal cycling caused it to loosen up, and that caused even more heating, and occasionally fires.

Stranded aluminum wire is large enough it is not used under plain screws, but in mechanical clamps that surround the wire and then use a screw to apply clamping pressure.
The wire is in a completely trapped set up preventing loosening of the conductor.

Given the price of copper wire, it might be worth using larger than required aluminum wire for a 200 foot run.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

He'd have to size up. As I said, it's hard to find Al conductors in smaller sizes. The minimum I'd find is #6. It might still be cheaper I guess.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

That was what I was thinking, just as the feed between the panels. The electrician who told me about it said the price difference was significant, and yes, it was extremely heavy duty.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Gentlemen, I just joined this forum and have a small experience to share about this subject, hope it helps?

Two years ago I installed a pool heat pump. I ran #2 aluminum tri-plex underground wire. But through conduit in a couple places above ground. The Aluminum was cheaper for me at the time cuz copper was sky high. But the distance from my 200 amp service panel to my pool heat pump was 110 feet. For that distance, the "chart" it required #8 copper or #2 aluminum. Using a 50 amp breaker.

I dug the trench and ran the wire myself. Scary for a beginner, but had lots of help from my dad over the phone and have built several homes and construction project that required a basic knowledge of the electrical trade. So it was no big deal.

Anyway, as I was saying, I would NOT recommend running any further than I did with aluminum cuz I had to "shave" the ends of the Aluminum wire just to get it into the terminals both at the panel and at the pool heat pump. I did NOT want to do it, but I already had the wie ran and buried and conduit done before I relized it. When I powered up the pump everything was fine, but I was worried.

Anyway, sorry for the long winded story. Just use what the distance chart tells you to use for your 200' distance. I would guess #6 copper. Then you also would be fine with your terminating.

Thanks, WORF333


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

WORF...Perhaps on the planet Klingon this is OK, but what you described is illegal by the [US] National Electrical Code. To do pools legally takes more than a basic knowledge of the electrical trade. Your further comments about "shaving" the wire make your installation even more suspect. The fact that the pump fires up is not a guarantee of a safe or effective installation.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

And on top of the "shaving" incident there is no grounding conductor in his aluminum triplex - yet another safety concern.

But hey - what do we know, the heat pump fired up and works...


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

The DB triplex has three insulated conductors, but I bet he didn't remark the neutral for ground use if he was using it for that. Another problem is direct bury of any form is NOT an approved wiring method for pools.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

"But the distance from my 200 amp service panel to my pool heat pump was 110 feet. For that distance, the "chart" it required #8 copper or #2 aluminum."

I'm trying to imagine what "chart" would have allowed #8/CU while requiring #2/AL for the same application. That's more or less a doubling of the ampacity. It must have to do with the distance column, eh?


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Woooo....there. I guess I should have addressed you gentleman as rabid dogs?! I was just trying to share my experience to help or warn the gent, of problems I had while doing my project.

Judgeing by the "negative tone" you people voice. I'm sorry I joined this site. It's too bad you guys get your jollies bashing others.

How about some common curtesy? Are you not members on this site to try and HELP others?

To answer some of your attacks:

1. Yes, the chart is for the voltage drop at longer distances.

2. The #2 Aluminum Tri-plex "underground" wire that I used meets electrical code for ALL direct bury.

3. Yes, of course one of the 3 wires was a ground wire.
4. Ron, enlighten me on the US National electrical code. As you put it, "To do pools legally". Oh master of all knowledge. The way you talk, I think you are more clueless on the subject than I am!

I agree with you all on the "shaving". I did not like it ethier, but I made the decision at the time. And it turned out fine!

I've been running the unit for over 2 years now with zero problems!

So, contrary to your gentlemans opinions, I was successful in my endevors and saved lots of $ doing it my self! If I thought I could not do it "safely" I would not have attempted the project!

Good Day, Gentleman


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

"Judgeing by the "negative tone" you people voice. I'm sorry I joined this site. It's too bad you guys get your jollies bashing others."

Doing it right is what the NEC (and local law that adopts it) requires.

"2. The #2 Aluminum Tri-plex "underground" wire that I used meets electrical code for ALL direct bury. "

Except a pool. A conveniently overlooked item.

Swimming pools have a dedicated code section.
Once you are soaking wet in the water you are a better conductor than the water it self *your dry skin was the major impedance to current flow).
Set up an electric field and the current WILL preferentially flow through you.

"I've been running the unit for over 2 years now with zero problems! "

Until a minor fault occurs and you energize the water and kill someone.

But you have obviously found a better way to do the job.

Many folks come here looking for a 'blessing' for sub-standard work.

I do not think you will find it.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

"4. Ron, enlighten me on the US National electrical code. As you put it, "To do pools legally". Oh master of all knowledge. The way you talk, I think you are more clueless on the subject than I am!"

Wow, talk about arrogant.

Here we have a guy who wires a poor heater, INCORRECTLY, gets called on his mistakes, thinks he is not wrong and tries to justify all his mistakes, and calls a qualified professional clueless.

Welcome to the forum, and good luck with that attitude. I'm sure you'll go far.

As for Ron being more clueless than you, you'd lose that bet, painfully. Your installation is unsafe and illegal. Sorry if these facts upset you. You are the typical person who hears something he doesn't like and goes on the offensive.

I say this from experience. I have done dozens of pool wiring installations and am very well versed in the code in this area. Many others heare are the same. Don't take these corrections/comments as attacks. Take them as constructive criticism. Constrictive criticism that could save your LIFE sir!


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

"The DB triplex has three insulated conductors, but I bet he didn't remark the neutral for ground use if he was using it for that."

I was thinking the unit was 120/240.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Yes, pools are a sore subject. You can get away with a lot of crap in DIY home wiring, but pools (spas, etc...) are not something to be playing amateur hour. Now if you're willing to sit down and read article 680 and make sure you understand all of it, that's another story. I've only done one real pool installation (but lots of spas which are in the same code article). You can bet when I did that pool I spent some time going over Art. 680.

WORF, as pointed out there are several things that you did wrong. I'm not sure which is worse, the ones you knew about and did wrong anyhow or the ones you didn't know about and you're risking not only yourself, but attempting to HARM OTHER READERS OF THIS FORUM by promulgating incorrect information.

Direct Bury of any cable is ILLEGAL by Art 680 of the NEC. You can not do this for pools


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

"It's too bad you guys get your jollies bashing others.

How about some common curtesy? Are you not members on this site to try and HELP others?"

Yes, helping others is the objective and, I'd argue, allowing questionable advice to stand without criticism is not helpful--whether out of courtesy or otherwise.

I can understand where you're coming from. It's true enough that you got hit with a $h1tstorm when you didn't expect it and, perhaps, some of the sarcasm was a tad OTT. I'm sure your original intentions were benign.

But this isn't about ego; it's about getting things right so that the OP doesn't act on faulty information. Sometimes it smarts to get called on a bad piece of advice but, IMO, it's what separates this forum from many other sources of DIY electrical advice on the 'net.

I think that if you review this entire thread carefully--and honestly--you'll conclude that the process here does allow for respectful debate and, more often than not, the result is a convergence or consensus on correct solutions, which sometimes means alternatives where there is more than one code-compliant approach.

If you choose to stick around here and find your advice questioned or criticized by one or more of the members in the future, skip the lip and simply ask for justification or explanation. It's a great way to learn and there's no tuition.

p.s. BTW, I'm a DIYer too and, to my way of thinking, it isn't always a matter of the pros being right all the time just because they're pros. However, when I'm wrong, I'd much rather be corrected (I actually want that!) than to mislead another DIYer. YMMV.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Gentleman,

Thank you for your attempt to be a "teacher" instead of the executioner, and for more of a polite demeanor. I DO appreciate constructive criticism. That is why I have joined this forum and welcome it. Without the "lip" as you have put it. I hope that applies to everyone here?

OK, back to the subject at hand. I'm assuming that you all agree with sticking to the #6 copper for this long of a run? Yes? To allow for both voltage drop and terminal size problems that the larger diameter #2 aluminum would cause, per my bad experience!? With the entier distance in conduit as you all are "by the bookers", Right?

Next, this is just a point of view so please could we put this into the catagory of "Honorable & respectful debate"

1. As I have stated in both previous thread entries. "I would NOT have attempted the project if I thought it was dangerous to anyone's safety"! So you all are saying that you "always" complete your "own" projects per the "letter" of the law and not the "spirit" of it. Meaning, on your own land when you know that if you where to deviate from the law/code, the chances of the "risk" taken is a billion to one shot of going wrong that you would still ALWAYS go by the letter of the law? In my opinion, The code is an "overkill" guide so that people that have very little common sense will not get themselves or others injured or killed. Agreed?

I know you gentleman do not know my abilities and or all my experiences, so your judgement would be flawed in that fact. But I live in the desert, if you know anything about the desert? You would know that the ground is like contrete. water does not penetrate. It runs off, going down hill, till it pools and then evaporates. So,:

1. Tri-plex underground is 100% safe (for pool application)where I live because NO water could ever reach the wire. And it rains very little here. And I live on a hill.
2. My pool heater is NOT an electric heater! It is a pool "heat" pump. BIG difference. The electric power to it runs a fan & a compessor. It's a heat exchanger. Basically, it takes the heat out of the air and puts it into the water.
3. The thick plastic around the wire & plastic conduit for that matter becomes very brittle and is degraded very quickly from the sun / UV rays, due to the 100 plus degree temps in summer and 320 days of sun a year. SO the best place for the wire IS underground. And metal conduit would just melt any plastic sheathing on wire from the suns heat.

So, this is why I chose the "illegal" way. The ONLY book I blindly trust is the "Good Book"!

Akrauus, I hope my opinion, experience and breath of freash air from the resident "by the bookers" will help you make an informed decision for your "freedom" of choice.

But I must say, I greatly value the by the bookers here too. Their opinoins also hold truth. As long as it is civil.

(Not aimed at anyone here on this site) There are so many people always forcing you into scams and making you spending huge amounts of $ through threats of fear to you and your family. If you do not conform to the the way "they" want you to do it. Why? Because "they" want us as "slaves" and NOT as free men!

Thank you Gentleman & good day!


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

OK, back to the subject at hand. I'm assuming that you all agree with sticking to the #6 copper for this long of a run? Yes? To allow for both voltage drop and terminal size problems that the larger diameter #2 aluminum would cause

I have no object to you using #2 Al if it were installed properly and legally. Tom was just pointing out that the the voltage drop upsizing you did seemed a bit weird #8 cu is rougly the same as #6 Al, but then go to #2 and he was wondering why (not that going way large is an issue.

So you all are saying that you "always" complete your "own" projects per the "letter" of the law and not the "spirit" of it.
Actually, I do. But if I weren't I wouldn't proudly proclaim that fact here, nor would I tell others that it is the correct way (or encourage them to break the rules).

The code is an "overkill" guide so that people that have very little common sense will not get themselves or others injured or killed. Agreed?
I disagree. The code is not overkill. It is in fact the minimal safety standard. Almost every change in the code is balanced by some loss of life that occurred in the past.

Tri-plex underground is 100% safe (for pool application)where I live because NO water could ever reach the wire. And it rains very little here.
I disagree. Not only is wiring for the pool required to be in conduit (and the fact that it might get wet is only a minor factor, underground wiring, even in conduit, is required to be wet rated. There are stringent requirements not just for the pool power but for all underground wiring near the pool.

2. My pool heater is NOT an electric heater! It is a pool "heat" pump. BIG difference. The electric power to it runs a fan & a compessor. It's a heat exchanger. Basically, it takes the heat out of the air and puts it into the water.
What difference does that make? The electricity doesn't care if it's supposed running a heat pump or resistance heater. It will fry you just as well either way.
The thick plastic around the wire & plastic conduit for that matter becomes very brittle and is degraded very quickly from the sun / UV rays, due to the 100 plus degree temps in summer and 320 days of sun a year. SO the best place for the wire IS underground. And metal conduit would just melt any plastic sheathing on wire from the suns heat.
You are further violating code if you're using non-UV rated conduit in a place where sunlight can degrade it.
) There are so many people always forcing you into scams and making you spending huge amounts of $ through threats of fear to you and your family. If you do not conform to the the way "they" want you to do it. Why? Because "they" want us as "slaves" and NOT as free men!
Compliance with the code and hence the LAW in most places is not a scam, It is what is right. You're not going to get anywhere here with your conspiracy theories or suggestions that basic safety considerations are spurious.

You're certainly not going to not get called on promulgating things that are
1. against the code.
2. and patently unsafe
as a legitimate way of doing things.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

OK, back to the subject at hand. I'm assuming that you all agree with sticking to the #6 copper for this long of a run? Yes?

No, I think the consensus was that #8 copper would suffice. The reason that's somewhat tentative has to do with the power demands of HVAC motors (i.e., a heat pump--and trust me, we do understand how a heat pump works).

Had this been a simple requirement for a 50-amp general purpose circuit, then I think #6 wire would have been the straight-up choice. However, HVAC equipment behaves a bit differently than a general purpose circuit in that it has both a minimum and maximum circuit ampacity rating and special code sections apply.

Cutting to the chase (and at the risk of oversimplifying), the minimum circuit ampacity is what the equipment needs to run after it has overcome the starting surge of its major component--the compressor motor. The maximum circuit is to allow for the starting surge, which can be several times the running load, lasts only briefly and does not pose a significant threat of overheating the conductors.

Thus, a heat pump is a specific situation where it is appropriate to use a larger OCPD (circuit breaker) than might ordinarily be used with a specific wire guage. But this isn't done by "guess and by golly"; it's based on the known faceplate ratings of the dedicated equipment.

In the thread discussion above, you'll note that there was some variance of opinion. Because I couldn't locate info on the minimum circuit rating, I initially took the conservative tack of recommending #6. (Forgive me if I'm wrong, but I think jmvd20 took a similarly "safe" route too.) At the very least, the OP would have a safe result that would be uncontroversial in the view of any inspector.

Ron, on the other hand, being more familiar with the particular type of equipment, was certain enough that the MCA was low enough to be fed by #8CU under these environmental circumstances. After some discussion about that, I'm inclined to agree with him although, as someone who doesn't deal with this equipment frequently, I'd tend verify the manufacturer's specs (which were not available online) before opting in that direction.

But I'd add that Ron's interpretation also satisfied my "common sense" test based on a rough guestimate of the approximate wattage consumed by a 5hp motor.

Thus, it isn't at all certain that #6CU is required. I believe the consensus is that #8AWG/CU is adequate.

"To allow for both voltage drop and terminal size problems that the larger diameter #2 aluminum would cause, per my bad experience!? With the entier distance in conduit as you all are "by the bookers", Right?

In making our recommendations, both Ron and I (and perhaps others) considered voltage drop at the 200' distance. Using 35 amps as the estimated running load, here are my calculations:

A 200' run of #8CU in conduit, delivering 35A at 240V yields a voltage drop of 4.9%, which is under the usual target of 5% (i.e., it's borderline, as I said, but acceptable). At 50A, the drop is about 6.5%--a drop that most motors can tolerate quite readily.

Under the same assumptions, if we use aluminum wire instead of copper, it will need to be upsized to #6 in order to meet ampacity requirements. Again at 200', the voltage drop calculations for #6 aluminum are very close to those for #8 copper (4.7% @ 35A and 6.8% @ 50A).

Any way you look at it, #2AL is way, way overkill for the OP's application. And that's why I called you on the statement that you used a chart that equated #2AL with #6CU due to the distance. That doesn't make sense to me and I'd love to see that chart.

Now, if it was the only underground-rated AL wire that happened to be available from your supplier, then fine, just say so.

Now here's what strikes me as particularly ironic: While you take issue with "going by the book" because, you contend, the book is mostly overkill, it was going by the book--strictly--that led the cost-saving recommendation to use a smaller and less expensive wire guage!

OK, sorry, enough of that.

1. As I have stated in both previous thread entries. "I would NOT have attempted the project if I thought it was dangerous to anyone's safety"! So you all are saying that you "always" complete your "own" projects per the "letter" of the law and not the "spirit" of it. Meaning, on your own land when you know that if you where to deviate from the law/code, the chances of the "risk" taken is a billion to one shot of going wrong that you would still ALWAYS go by the letter of the law? In my opinion, The code is an "overkill" guide so that people that have very little common sense will not get themselves or others injured or killed. Agreed?

No, not agreed. In fact, the less you know, the less capable you are of assessing the risks and, therefore, there's all the more reason to adhere to code strictly.

Personally, I'll admit to doing some pretty half-a$$ed things in the past but, honestly, the older I get (I'm 62 now), and the more I learn, the more I do, in fact, "complete [my] 'own' projects per the 'letter' of the law."

As for the code being "an 'overkill' guide so that people that have very little common sense will not get themselves or others injured or killed", I agree only to the extent that there are certain safety margins built in, much like there is a over-design requirement when engineering a bridge. And I'd also agree that a few of the requirements seem like unnecessary nuisance and expense--child proofing all the receptacles in an adult-only home comes to mind. But even there, standard requirements contemplate not only your personal requirements and tolerance for risk, but those who may occupy the premises at a later time.

As the code evolves, with new editions coming out every three years, a great many of the new requirements are based on actual documented experience. That is, there is statistical evidence of a problem that caused actual fires, actual injuries and actual deaths. Since there are only about 300 million people in the U.S., these problems are not in the order of one in a billion or they would not have statistical support.

3. The thick plastic around the wire & plastic conduit for that matter becomes very brittle and is degraded very quickly from the sun / UV rays, due to the 100 plus degree temps in summer and 320 days of sun a year. SO the best place for the wire IS underground. And metal conduit would just melt any plastic sheathing on wire from the suns heat.

No one here disputes that the OP's proposal to run the conduit underground is a good idea and I certainly didn't hear anyone suggest metal conduit.

Interestingly, if you familiarize yourself with the code, you'll discover that all these factors are well-accounted for. Ambient temperature, for example, is a definite factor in selecting cables and wires. So, too, is sun exposure. Where conditions fall outside normal expected ranges, there are wire types and methods specifically designed for such conditions.

BTW, if you post for advice here, make sure to mention that your project is in the desert where the temperatures and light exposure are very high and you'll get competent advice for those conditions.

In sum, there is no real reason to "choose the 'illegal' way."

Jes my 2c and a "good day" to you too, sir.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

I stated that #6 needs to be used because even though this unit is a "heat pump" to me it still utilizes electrical current to heat the water and therefore would fall under the requirement of 680.9 Thus requiring that the ampacity of the branch circuit conductors and overcurrent devices shall not be less than 125% of the nameplate load.

Of course at the time I thought the nameplate was 50 amps but apparently it is not that high. I think it is strange though that they did not list the actual load on the specs - they only specified the breaker size.

In the end though - I must admit that I usually do upsize wires whenever they are close to the maximum allowed amount when it comes to installations such as this.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

No, the installation instructions for this device say it requires a 50 Amp dedicated circuit. I checked that early on. My guess that it only draws 32A was working backward from the specsheet SOLELY to determine what the voltage drop might be on this like to see if upsizing above code requirements might be advisable.


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RE: Cost of Wire for 200 Foot Outdoor Run From Pool Heat Pump

Thank you Gentleman for your truely inspiring insight and experience. It's been a pleasure. On future electrical projects I WILL return to this site!

Thank you all and Good Day!


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