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Subject - disconnects
cs409 Need some input... any one having to install disconnect at hot water heater? thanks
JimmyDee
quote:
422.47 Water Heater Controls.
All storage or instantaneous-type water heaters shall be equipped with a temperature-limiting means in addition to its control thermostat to disconnect all ungrounded conductors. Such means shall be as follows:
(1) Installed to sense maximum water temperature; and
(2) Either a trip-free, manually reset type or a type having a replacement element. Such water heaters shall be marked to require the installation of a temperature and pressure relief valve.
Exception No. 1: Storage water heaters that are identified as being suitable for use with supply water temperature of 82°C (180°F) or above and a capacity of 60 kW or above.
Exception No. 2: Instantaneous-type water heaters that are identified as being suitable for such use, with a capacity of 4 L (1 gal) or less.
FPN: See ANSI Z21.22-1999/CSA 4.4-M99, Relief Valves for Hot Water Supply Systems.

Quoting from Ray C. Mullin's book Electrical Wiring Residential he says, that 422.30 requires that all appliances must have a means of disconnect. He says, "this would normally be located in the panel (load center) or it could be provided by a separate disconnect switch. 422.34 allows this to be an integral part of an appliance having an OFF position that disconnects all ungrounded conductors from the source..... In many local codes, this is not acceptable."
quote:
422.30 General.
A means shall be provided to disconnect each appliance from all ungrounded conductors in accordance with the following sections of Part III. If an appliance is supplied by more than one source, the disconnecting means shall be grouped and identified.
422.31 Disconnection of Permanently Connected Appliances.
(A) Rated at Not Over 300 Volt-Amperes or Horsepower. For permanently connected appliances rated at not over 300 volt-amperes or hp, the branch-circuit overcurrent device shall be permitted to serve as the disconnecting means.
(B) Appliances Rated Over 300 Volt-Amperes or Horsepower. For permanently connected appliances rated over 300 volt-amperes or hp, the branch-circuit switch or circuit breaker shall be permitted to serve as the disconnecting means where the switch or circuit breaker is within sight from the appliance or is capable of being locked in the open position.
FPN: For appliances employing unit switches, see 422.34.


Jim
cs409 maybe i should clear up my post..... is any one having to install a disconnect at the water heater location in addition to the circuit breaker in the panel that feeds it?? such as used or simular to an AC outside unit! thanks...
JimmyDee Maybe I should clear up my answer. It is not required by the NEC. It is a local issue and no one here in my area is requiring it and don't know where they are.
Jim
SteveMc Our local inspectors require a disconnect if the water heater is more than 25' from the panel. Just to the north of me in NC you are required to have a disconnecting means on the dishwasher as well.
JimmyDee
quote:
Originally posted by SteveMc

Our local inspectors require a disconnect if the water heater is more than 25' from the panel. Just to the north of me in NC you are required to have a disconnecting means on the dishwasher as well.

The dishwasher is a no brainer if they require one. Just purchase a #12 cord set and plug it into a 20 amp repept.
Jim
Electricman The Inspectors we use insist upon a disconnect if the water heater is not within sight of the panelboard. Such a case would be in a dwelling that has the service in the garage and the water heater in the basement.Also I have had to install a disconnect when the water heater is in a seperate mech room or closet than the panel.
cs409 i havent ran into this to date, but had a conversation with electrican friend and he was told to install one!,,,he was green lighted on this remodel job, but the inspector knows the disconnect will be installed!
A lot of new/weird things taking place in my area LOL....not to mention my funny spelling (simular/similar)please correct any u see!
cs409 P.S. i have no problem with the disconnects..it is/could be a very good thing to start installing.
David Hyatt I learned something here. I thought it was code to have to have a disconnect within line of sight or a lock out on a water heater and dishwasher. Thats what they require here. But I see if it is not over 300 volts its not required.
JimmyDee Thats 300 volt-amps David.
Jim
SteveMc
quote:

The dishwasher is a no brainer if they require one. Just purchase a #12 cord set and plug it into a 20 amp repept.

Actually I always run a 14/3 to a two gang switch box and then drop out of the switchbox (2) 14-2's, one to the dishwasher and the other to the disposal. Then hard wire both of them. I never did like to have a receptacle behind the dishwasher, personal preference.
David Hyatt Jim, in this code ref. what is the difference. 300 volts, 300 volt-amps. Volt amps= apparent power. Please explain.
I do use a lot of lockouts in my area. Just had my supplier to special order lockouts to fit GE thin style breakers.
JimmyDee On a resistive circuit, volt-amps is for all intents and purposes, is the same as watts. What they are telling you is that if your water heater is 300 watts or more (or VA), those rules pertain to it. If it is less than 300 watts, they don't. (No flames please, I know the difference between watts and VA)
Where as volts is just that no power until the amps are added. Volts is the amount of pressure and amps is the amount of flow. Watts or VA would be the gallons in a given time.
A lockout for the breaker at the panel looks to me like it meets the requirement.
Jim
cs409 call it coke or call it water lol,,,,i havent had to install any to date,,,, just was told this is/was required in one of the cities in my area,,,,what u can do in one of these cities you cant in another,,basic like any other metro areas,,,i have been in quite a few new homes, with E hotwater heaters,,,,havent seen any disconnects/lockouts etc...but i will be looking.......one thing i have found,,,some new reuirements they sorta ease u into and some they hammer u into using! thanks for all the input.
cs409 just a thought/question,,,,havent researched this either so yall throw your usuall good responses in .....could you install a proper cord/plug and just plug the puppy in like you do a dryer?
JimmyDee
quote:
Originally posted by cs409

just a thought/question,,,,haven't researched this either so yall throw your usuall good responses in .....could you install a proper cord/plug and just plug the puppy in like you do a dryer?

Don't know why not. It is an acceptable disconnect.
Jim
Electricman The way I read 400.7(A)8 I dont think using a cord and plug would be code compliant. My Interpretation is because cords shall only be used on appliances when they can be readily removable(ie. range) a water heater that is attached by solder joints to the residence dwelling would violate this.
JimmyDee Looks like you are correct. No cords.

Jim
cs409 grey/gray area guys? where is Ryan? a dish washer has a water line which requires wrenches to remove said water line and a discharge line(i know, one screw on clamp)....... water heaters do not have to be solder joints, you can use screw on connections...so!!! this is a fair and interesting post...
Ryan_J
quote:
Originally posted by cs409

grey/gray area guys? where is Ryan?


Ryan was in Montana enjoying Yellowstone all week :)

If the inspector is requiring a disconnect, I would ask him to show you a code section. Would he/she allow a "lock-off" mechansim in the panel, as permitted in the NEC?
cs409 did you see yoggie and boo boo? not sure on any of this,,,,but u forgot one thing,,,,local dos and donts list? so if the city requires it? so be it right? as i said in earlier post,,,i have to date seen one or used one or the lock outs, but i will be a bit more eagle eye over the next couple of weeks!
cs409 Ryan....could one use a cord and plug on a hot water heater? and if so, would this satisfy the disconnect requirement?
David Hyatt With Jims explanation of volt-amps, I don't know what I was thinking, volt-amps; apparent power or watts. I knew that had a brain cramp. Then a disconnect is required in line of sight of a water heater. Or a lockout is required.
Cord and plug connected also seems code compliant.
JimmyDee
quote:
Originally posted by Electricman

The way I read 400.7(A)8 I dont think using a cord and plug would be code compliant. My Interpretation is because cords shall only be used on appliances when they can be readily removable(ie. range) a water heater that is attached by solder joints to the residence dwelling would violate this.

quote:
400.7 Uses Permitted.
(A) Uses. Flexible cords and cables shall be used only for the following:
(8) Appliances where the fastening means and mechanical connections are specifically designed to permit ready removal for maintenance and repair, and the appliance is intended or identified for flexible cord connection

This should answer the question.
Jim
David Hyatt I buy that Jim. Makes good sense to me.
Ryan_J I think Jimmy cites the proper code sections, but I have never (personally) seen a water heater identified for use with a cord and plug.
cs409 "but I have never (personally) seen a water heater identified for use with a cord and plug." Ryan, yes u have, think hard LOL...u know u have!!
Ryan_J
quote:
Originally posted by cs409

"but I have never (personally) seen a water heater identified for use with a cord and plug." Ryan, yes u have, think hard LOL...u know u have!!


Well....um....let's see....uh....Nope.
cs409 at 25 and hanging out in Jellystone park or was that yellow something park? you may not have seen one LOL.....but keep thinking about this.