# Homemade electric pool heater



## taylorjm (Apr 11, 2013)

Ok. So here is what I have. The kids have a 16' pool we setup in the summer, and I used to have an old spa heater I used in the spring to get things heated up until the summer. Well, it died, so I built another one. I used 2 - 3000w water heater elements threaded into 2" tees interconnected so the water flows into one tee, then into the other, then out. I only have 3 wire 220v outdoor cable run to the pool to run the elements. I have a 120v switch and relay to turn the elements on and off, and they run off a second 120v gfci plug. So yes, I have to plug in the 3 wire 220v, and the gfci 120v plug at the same time to turn the heat on. (the 120v is plugged into a totally separate outlet, nothing to do with the 220v line) Which is fine because I can put the 120v relay on a timer to run with the pump. The 220v line has the 2 hot lines, and a ground line tied back to the main panel where the ground and neutral are tied together. 

I have the ground lines from both the 220v and the 120v lines going to the metal pipe.

I haven't had the guts to plug it in yet, even though I can't see why it wouldn't work, except I'm concerned with the 220v line. I know with a water heater, they are usually 3 wire and grounded to the water tank, which is similar to what I have done, so I don't know why it wouldn't work. I'm concerned that somehow, either the pipe or the water are going to get electrically charged because the ground (which is also the neutral since they are bonded at the panel) are going to complete a circuit. Can anyone give me a second opinion?


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## jproffer (Mar 12, 2005)

I don't think I would use a homemade...ANYTHING electrical...in a pool.

I can't give any particular reason other than that it just doesn't seem like a good idea.

Sorry I can't be more specific, or give you the second opinion you're looking for.


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## biggles (Jan 1, 2008)

get that contactor away from those pipes and lead the elements out thru a chase into a seal tight box.... where are the elements:huh: with the disconnect /CB on but not calling that are should be dead of power not within....:thumbsup: should of PVC'd the pipes


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## brric (Mar 5, 2010)

My opinion is that I don't know why anyone would put some kids in jeopardy just to save a few bucks.


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## micromind (Mar 9, 2008)

I'd highly recommend using a two pole GFI breaker for the 220 to the elements. I'd also solidly ground the pipe that the elements are in. 

Is there any kind of interlock that will de-energize the elements in the event of no water flow through them? 

If an immersion element is energized when there's no water flow, it'll burn up quickly. And even worse, very often the outer sheath will rupture, allowing water to contact the energized part of the element. This will trip the GFI (if there is one). If there isn't a GFI, then in theory, the ground will maintain a low enough voltage gradient to not be harmful, but I wouldn't bet on it. 

Properly protected, this set-up will work well. 

The two elements combined will draw about 25 amps at 240 volts. 

Rob


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## taylorjm (Apr 11, 2013)

I will put a gfi breaker on the 220v side.

I don't have a flow sensor, but was going to put the pump and the heater on the same timer so the pump will be running with the heater, but if for some reason it doesn't, yes the elements will burn up. But I figured the cost of the elements are under $40, so I wasn't really too concerned about it, but I will put a gfi on the breaker because I didn't think about what would happen if they burned up.

The wire will handle at least 40 amps, and the current breaker is a 30 amp, so I should be set with that.

What do you mean about solidly grounding the water pipe? You can't see it, but the ground wires coming in are attached to the metal strap holding the iron pipes in place. It's a very tight connection to the iron pipe. Do you mean I should add a ground rod outside? I thought the only place you should ground is at the panel.


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## k_buz (Mar 22, 2012)

Can we lock this thread now? 

This might just be the dumbest, most dangerous post I have read on this forum. Sounds alot like Russian Roulette to me.


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## chitownken (Nov 22, 2012)

Do you have temperature limit sensors on the outlet pipe? You don't want to be pumping 150 degree water into the pool if the flow rate slows down due to dirt in the filter.

I tend to agree with brric.


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## taylorjm (Apr 11, 2013)

K-buz. Do you have something constructive to add to this thread? Otherwise, maybe you shouldn't associate with people who's intelligence is so far beneath you. Since this is a DIY forum, I'm guessing you are in the wrong place.


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## k_buz (Mar 22, 2012)

We don't help people build death traps.


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## taylorjm (Apr 11, 2013)

brric said:


> My opinion is that I don't know why anyone would put some kids in jeopardy just to save a few bucks.


Can you be more specific as to what part you don't think is safe? That's what I'm trying to find out.


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## BigJim (Sep 2, 2008)

Due to the potential dangerous nature of this situation, this thread is closed.


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