Disconnect means for instant hot water

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mrvoltamp

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I will be installing a instant hot-water heater. It requires 3, 50 amp, 240v circuits.The main panel is in a seperate location. I have installed 1 of these in the past. I installed 3 seperate 60amp non-fused disconnects. My field manager is telling me that the disconnects are not necessary, that breaker locks in the main panel is sufficient. I have combed thru Art. 422 and cant find the answer. Art 422.31 (a) is the closest I can come to an answer. That would make my Boss right, However I have been told in the past that if the water heater is not located in the same room as the panel then it requires a disconnect. Please help?

Thank you.
G-
 
Thanks Cow, after looking back thru 422.31(B) I see where this would have saved me alot of time and effort with regular water heaters. Something is telling me that because this one is using 3, 2 pole 50amp breakers 422.31(B) is not gonna work here.

Lets say a plumber shows up to work on the appliance. He goes to the panel,opens the door see's a 2p 50 breaker marked water heater and turns it off. Not knowing there is two more to turn off. It could get ugly quick.

Do they make a breaker lock for 3 2p breakers to shut them off all at once?
 
Thanks for your responses. I guess I can handle tie the breakers together. I will just have to do some rearranging in the panel. Just makes me a little mad that I have been installing disconnects all this time and didnt have to. Thats what I get for assuming my former employer knew everything. Should have done the research myself or better yet, just asked you guys. Thanks again everyone.

G-
 
mrvoltamp said:
Thanks Cow, after looking back thru 422.31(B) I see where this would have saved me alot of time and effort with regular water heaters. Something is telling me that because this one is using 3, 2 pole 50amp breakers 422.31(B) is not gonna work here.

Lets say a plumber shows up to work on the appliance. He goes to the panel,opens the door see's a 2p 50 breaker marked water heater and turns it off. Not knowing there is two more to turn off. It could get ugly quick.

Do they make a breaker lock for 3 2p breakers to shut them off all at once?
Click to expand...

Why would you want to turn off all three if you're only going to work on one of them? You are talking about three water heaters aren't you.
 
George Stolz said:
Especially if this water heater is in a pipeline or a vessel... :-?

My thought was, does 210.7 have a say in this?
Click to expand...

Yeah, I didnt think to look there for that reason. The water heater is gonna be located in a maintaince shop in a factory.

I should also have mentioned, we are still under the 2002 code. I looked in my book at Art.210.7 and its for lighting outlets required.
 
mrvoltamp said:
Lets say a plumber shows up to work on the appliance. He goes to the panel,opens the door see's a 2p 50 breaker marked water heater and turns it off. Not knowing there is two more to turn off. It could get ugly quick.

Do they make a breaker lock for 3 2p breakers to shut them off all at once?
Click to expand...

How about getting a phenolic nameplate made that warns anyone working on this unit that it has 3 disconnecting means located in the panel.

As an Inspector I would ask you to provide this type of warning tag on it, if you did not have the disconnects at the water heater itself.
 
mrvoltamp said:
Thanks for your responses. I guess I can handle tie the breakers together. I will just have to do some rearranging in the panel. Just makes me a little mad that I have been installing disconnects all this time and didnt have to. Thats what I get for assuming my former employer knew everything. Should have done the research myself or better yet, just asked you guys. Thanks again everyone.

G-
Click to expand...

IMHO, and I bet the opinion of others, your original method is a lot safer than "breaker locks". I personally feel they are practically worthless. So don't be mad, be proud that you enhanced the safety issue.
From my experience, when breaker locks are available in these type situations, they are seldom used. A readily accesible disconnecting means is far more like to be used.
 
I agree with Gus it is much safer to do the 3 disconnects at the unit and I do not care for breaker locks. If equipment needs a disconnect means then it should be a disconnect. I perfer the disconnect at the equipment.
 
I agree a disconnect within sight is the best option,but sometimes it's not
practical to install a large disconnect next to a Insta-hot. So in that case
I'll use a breaker lock out. When using a breaker lock I always place a label
on the unit "Breaker Lockout for this unit located in 4th floor electrical room
panel PA1N-2,4,6", using a P-Touch label maker.

Before running out and buying breaker lockouts make sure you read
Art.422.31(B) carefully, you must be able to put a "lock" on it. I can't tell
you how many times I've seen breaker locks used as disconnecting means
that were the "Set-Screw" lockouts. "Set-Screw" breaker lockouts are
not in compliance with 422.31(B).
 
Remember that local codes/building codes supercede the NEC.

There are some jurisdictions that require the disconnecting means for water heaters to be installed in the same room/space as the unit. I have run across this the hard way...a building inspector coming behind my inspection. I believe they call that "live and learn."
 
I do hope you understand what this type of load does to a typical home. They will be calling you in a few days saying the lights are diming and flashing. Your also upseting the poco with that type of demand. While a tag saying there is more than 1 breaker is smart i dont think its required. I installed one of these that had 3 of the 8 kw strips. We removed 1 because it was really over kill and owner hated the flashing. Plumbers will sell anything to make a buck.
 
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