Branch circuit Taps

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Micksbroke

Micksbroke

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Gainesville, Fl.
I have had a new type of water heater to hook up. Its from Germany. Its a instant hot type.
The book says it requires 2- 40a circuits. 1 per canister, But the Name plate says 52a combined (both canisters) So I ran 2-#6 and grd. on a 60a breaker. So I Took the Polaris taps and split circuit at the unit, to both canisters. (208v each)

I thought the Tap rule applied and made since. He says it does not apply. I treated it like a wall oven with a cook top on same circuit. He said that's not legal also. (Am I reading 210.19 (A) 3 wrong?)

Did a load check by running hot water for 10min +/-. Its 52a on the money. It's not considered a continuous load.

The inspector says he don't like it... Does 210.19 (A) 4 not apply?

The WH book states 2 circuits. But that's 2- 2pole circuits per 1 unit. No UL listed handle tie available for two 2pole breakers. This could be a dangerous situation and the Tap was less dangerous...I thought.

Any suggestions or guidance is valued.
 
Its a water heater !!
210.19(A)(3) addresses Household Ranges and Cooking Appliances.
210.19(A)(4) addresses Other loads and gives minimum sizes of conductors.
240.21 addesses overcurrent devices as related to tap conductors. I most of the situations covered by 240.21 the tap conductors terminate at an overcurrent device.
Did your tap conductors terminate in a method prescribed by 240.21
Does the mafg . instructions call for two 40 amp circuits ?
 
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I would set a small panel and install 2 circuits to the unit. The tap rule does not apply since the unit calls for 40 amp overcurrent protective devices. There may be other reasons it does not apply also.

The cooktop/range tap could be compliant depending on where they are located etc. I disagree with the inspector on that one but he is correct on the water heater, IMO
 
Ok. Been busy, couldn't get back to you guys. Thanks for your thoughts.

So the tap would have been correct if the were at the OCP not at water heater?

Why doesn't this fall under "other Loads" in 219. (A) 4. Its not in 210.2 chart, its not cooking.
 
Assuming 210.19(A)(4). That section specifies the "Branch Circuit Ratings" as noted in the header and (A)(4) addresses minimum ampacity when supplying other loads.
You would need to comply with that section as far as the wiring not being smaller than #14, but you still need to comply with 240.21 tap rules as far as overcurrent protection.
 
Did you use #6 for everything, or reduce it down to #8 for the 40A taps? If you kept it all at #6, then these wouldn't be taps but just normal circuit branches. Then issue then becomes, are you permitted to have a 60A overcurrent device on the lugs feeding what was intended to be fed from a 40A overcurrent device. There is a rule in 422.11(E) and (F)(1 and 3) (not sure which is more applicable) which allows a larger than normal overcurrent device. But I see a lot of thin ice here and you'd need to carefully read the sections, and look at the labeling on the heater and in the instructions. If it indicates a max of 40A breaker, or the heater is labeled "40A breaker", then you're going to have to install two circuits.

A handle tie for two double poles is not required. Having multiple circuits going to one instant water heater is quite common. The same can occur on electric furnaces as they tend to have subdivided heating elements as well. I'd just make sure to group them and label them well.
 
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