My contractor installed water tank


and it ran for a short while (not sure how many days or weeks) before it’s dead. No hot water, no power in the tank, element burnt.

We replaced another new one but in the process we found out the circuit breaker was one leg burn


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My electrician said whoever installed it actually crossing the legs so they can get 240V.

The new one (red) looks like this after he replaced


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My question is: How is it even “possible” to install the breaker like that to get 240V? Does it mean “someone” has to bend the breaker fitting and force it in? I asked because the evident were gone and I wasn’t home. What’s exactly behind the panel that allowing such installation to create 240V for a small 2-pole? Is it “legal”?


  1. So my contractor said that the red double pole 20A now is 40A / 240V total. But does it mean "before" there were multiple circuits but now there is only ONE big circuit. Should I be concerned about overload?

  2. There is a subpanel in the house. The photos above are the outside panel located in back of the house.

  3. The wire is 10/2 but it is non-stranded. I don't know if 10 AWG Stranded is a MUST/REQUIRED here or 10/2 is enough.



  • Paint the Square D breaker or a Challenger breaker red and put it on top of the burned up bus stab. Don't use it.
  • Replace all black Challenger breakers with Eaton BR/C
  • Check technicolor BRyant breakers and make sure they are cross-listed Type C; if not replace with BR/C
  • Make sure water heater wire is 10 AWG
  • Replace water heater breaker with 25A BR/C
  • Rearrange all breakers to avoid burnt up bus stabs
  • think future subpanel

Abducted by alien breakers

We talk a lot on this forum about alien breakers. This panel is the picture postcard example of why. But it also has some interesting exceptions.

This is a Challenger panel. It requires Type C breakers. Nothing else will do. Yes, other types of breakers will snap in. But they won't fit, and this is what happens.

The breaker your plumber used was a Crouse-Hinds, which only works in Crouse-Hinds panels. It uses a trick we've seen in the GE Q-line, which is to have a 1-space breaker straddle 2 spaces, with a 1/2 space hole above and below (which you're supposed to fill with companion 1/2" breakers).

Point is, that Crowse-Hinds is seriously wrong in your Challenger panel. Obviously, the plumber had it lying around and couldn't be bothered to pop into any store and get a BR220. The Eaton BR line is cross-listed Type C.

A shame the classic breaker was destroyed by ineptitude. Unfortunately, its destruction also took out the bus stab. Certainly the melted one, possibly the other tapped one as well. That stab is dead; put any old 1-pole breaker there and don't use it. I would paint the breaker red to indicate it's not for use; you wouldn't want someone trying to use it by accident.

Additional breaker issues

With a Challenger panel, you are blessed that Eaton type BR is compatible and cross-UL-listed for Type C. That means UL gives the fullest endorsement possible for a breaker. (The alternative is a UL-Classified breaker, made specifically for panel X by competitor Y and passed UL safety testing.) Eaton BR/C is the correct breaker for your panel. And they're $5!

However, actual Challenger branch circuit breakers are known to be defective. The panels and bus stabs are fine. Well, yours are a bit corroded and could stand a pass with a wirebrush to see if they're solid underneath, power off of course! I presume this is an outdoor panel.

So every Challenger breaker should be replaced - those are the older all-black ones with the 7-segment-display style lettering.

The remaining ones are actual BRyant, you can tell from the multi-color breaker handles. Look closely at those and make sure they are actually cross-listed Type C; Bryant breakers are reliable but they might not fit the panel. Modern Eaton Type BR/C are readily available at sane cost ($4.50/pole).

The only ouchy price in there will be that 100A that feeds your subpanel; bring $50 for a BR2100. That is on the top of the hitlist for being replaced. Further, the breakers across from it must never be larger than 20A and can't be double-stuff -- otherwise you'd put 130A++ on those bus stabs the 100A breaker is using. They are only rated for 125A.

Lastly, there's the remaining alien breaker, the Square D HOMeline double-stuff. That is fine as only a hole-filler since the bus stab underneath it is burned up and unusable.

However, it is in the wrong place. I believe the burnt stab is the one below. The newer Bryant 2-pole breaker is there instead, and probably not working because the stab is burnt up.

The better plan: another subpanel

Replacing a panel can be heinous. So I suggest installing a subpanel either right next to this one, or some appropriate place (like where all those cables go). Have this panel have nothing in it but two 100A breakers feeding said subpanels. (And space-occupying breakers to nothing, to fill the holes).

Do not put the second 100A breaker across from the current one, for stab limit reasons. Put it below.

That 20A water heater circuit

This is a 4500W water heater. Applying the mandatory 125% derate, we need to provision 5625W of power. That requires a 25A breaker and therefore 10 AWG wire, as indeed called out on page 8 of the manual.

This we know. That plumber needs to stick to pipes!

Legionella bacteria kills

Looking at that manual, I see that it doesn't talk about the dangers of legionella and other bacteria breeding in a hot water heater. This is a recent scientific discovery, and the didn't update the manual because it's part of the UL listing for hundreds of products; changing it voids the UL listing for all of them.

It does warn about scalding, and you do indeed have to balance the risk of scalding vs the risk of legionella and friends. (Scalding is not an issue if you have thermostatic "joystick style" knobs). I suggest reading the latest literature and making up your own mind.

  • The old breaker was a Challenger half-width, two pole (Type A) not Crouse-Hinds... – ThreePhaseEel Nov 23 '19 at 19:52
  • The water heater is 240V and 20 Amps. I posted link above – HP. Nov 23 '19 at 20:05
  • @HP. what wire size was used for the water heater circuit? – ThreePhaseEel Nov 23 '19 at 21:58
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    @NoSparksPlease I gather that the plumber fit the Crouse-Hinds, not the electrician. The electrician fit a BRyant. Somehow both of them have a time machine back to the 1980s, I can't imagine how else Crouse-Hinds and technicolor BRs are the easiest breakers to get. – Harper - Reinstate Monica Nov 23 '19 at 22:51
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    @Harper I figured the electrician was told it fed a water heater, anything but a 2P30 I woulda taken a look at tank label. – NoSparksPlease Nov 23 '19 at 23:05

The Square D breaker you have in there now and the burnt breaker (Challenger A240 ?) are not functionally the same, the burnt breaker is a two-pole 240v breaker.

Would need a "before" picture too, but the breaker you removed would need to be spaced one half space lower than the Square D you have in there now. It would give 240v when properly installed.

It could have been a damaged or defective breaker out of the box, and the clip just didn't make good contact, but looking at the busing where you now have the red handled breaker to me it looks significantly oxidized already. I would suspect the tiny clip on the half space breaker didn't make good contact with the oxidized bus, and that caused the overheating.

Really the condition of that bus makes me think the panel effectively reached end-of-life before the water heater was added.

  • Can you elaborate on this “ The Square D breaker you have in there now and the burnt breaker (UBI/Conn El type A?) are not functionally the same”? – HP. Nov 23 '19 at 18:29
  • Are you confident this is a Crowse-Hinds panel? Because if so, every breaker in it is wrong, and the failed breaker shouldn't have. – Harper - Reinstate Monica Nov 23 '19 at 18:33
  • The SD has a single clip on the back of the breaker, only one bus attachment, both spaces feed from the same leg. You can see the breaker attachment is in the center of the breaker. The old breaker had two clips to attach to the buses, clips are on the edges of the breaker, giving 240v between the two terminals.. – NoSparksPlease Nov 23 '19 at 18:34
  • @Harper - This is a new property I just bought so I don’t know what panel it is. I am far away. How do I find out about Crowse-Hinds panel? What is it in relation to the ways these breakers are mounted? – HP. Nov 23 '19 at 18:36
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    But looking at the paint style it is probably an old stock Challenger Type A. – NoSparksPlease Nov 23 '19 at 18:54

You have some...clean-up work to do here

What your installer did was a parts-off-the-truck hack job to get 240V out to your tank. However, it certainly isn't a proper job, given that they put an alien breaker in your panel!

Given the current state of the panel, what I would do for now is:

  • Remove the BD2020 and the C115 breakers in the top right and discard the C115. This then frees up two slots for a BR225 to be fitted top right in the panel, which'll become the new water heater breaker
  • Land the 10AWG wires for the water heater circuit (the existing solid wire is fine, NM in sizes from 14AWG to 10AWG always uses solid wire) on the new water heater breaker, and remove the BR220 from the bottom right and discard it
  • Remove the HOMT2020 from the middle right of the panel, discard it, and replace it with the BD2020 that came from the top right.
  • Move the hot wire from the C115 near the bottom left to the BR115 below it.

This way, you have the correct breaker and wire for your water heater mounted on a set of stabs that should be undamaged; the existing BR220 that's trying to feed that circuit is sitting on bus stabs that probably were slow-cooked by trying to push a 20A breaker to its limits for hours at a time, which is why it's not having a good time of it. This also means we aren't using the crusty Challenger-made Type C breakers any more than we have to, and also means we can think about replacing this panel at some point.

As to how that Type A two-pole half-width breaker worked...

The Challenger Type A is a half-width breaker type; this is one way to do "double stuff" breakers (the other being "tandem" breakers such as the BRD2020 in the top right of your panel). As a result, instead of having a jaw centered in the breaker housing that clamps over the busbar stab for that pole, your A220 used a jaw that sits on the edge of the breaker housing and rides on half of the stab, leaving the other half open for another half-width breaker to be slotted into place there. However, this makes for smaller stab-to-jaw contact patches, making it a less reliable design than one that uses full-width jaws, especially in the face of abuse such as what your original breaker experienced.

As to amperage rating -- your contractor is just plain confused here; a 20A breaker is a 20A breaker, no matter what voltage it's rated for or how many poles it has. Furthermore, the water heater circuit is a single (240V) circuit that powers a single piece of equipment (namely, the water heater), so anything your contractor was saying about "multiple circuits" was total gibberish and should be ignored outright.

Longer term plans: replace this panel

In the longer term, this panel will need replacement, simply due to its poor condition, what with the severely damaged bus stabs in the bottom right and all. While panel space isn't an immediate concern due to the fact that it's feeding an indoor subpanel, I would look to put something larger than a 12-space panel in here when it came up for replacement, provided space permits. You'll need a 200A, main breaker, NEMA 3R (outdoor) panel in any case, along with a 2-pole, 100A breaker for the feeder and a 15A, 1-pole breaker to replace one of the Challenger C115s. If you're using an Eaton BR for the replacement panel, the BR225 that's serving the new water heater, the BRD2020 tandem breaker, and the other BR115s (with the blue handles) can stay, otherwise they'll also need to be replaced with suitable types for the new panel.

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