2 prong Ungrounded outlets

[480sparky]

Point load on NM wiring:
View attachment 2552152 View attachment 2552153

I often see one in every room in a 1950's house.

Oh, you mean high-amperage loads!

 

[hbiss]

And it is up to the buyer to make sure it is done. It is their loan not the sellers loan.

Exactly. They are the ones who applied for the loan and should know the terms. So don't look at old houses that you know are not going to meet the requirements and have the crust to demand that the seller make improvements so you can get your loan. And of course their Realtor is going to back them up because they want their commission.

-Hal

 

[LarryFine]

Oh, you mean high-amperage loads!

I actually meant high-amperage loads made of a group of lower-amperage loads plugged into a single point (one receptacle with power strip(s) plugged in) on a circuit, but the result is the same.

I prefer running a new circuit for such loads (as well as heaters) which both serves the loads better and conserves the house's GP receptacles for the usual expected loads like room lighting, etc.

 

[480sparky]

I actually meant high-amperage loads made of a group of lower-amperage loads plugged into a single point (one receptacle with power strip(s) plugged in) on a circuit, but the result is the same.

I prefer running a new circuit for such loads (as well as heaters) which both serves the loads better and conserves the house's GP receptacles for the usual expected loads like room lighting, etc.

That would be a neat trick... predicting where in a house someone is going to plug in a 1500w heater.

 

[LarryFine]

That would be a neat trick... predicting where in a house someone is going to plug in a 1500w heater.

When I was a helper, one of the first jobs I was given to do on my own was to install one new receptacle in each room, each on its own circuit, for portable heaters.

 

[jap]

I would tell them to pound sand. This is my price, take it or leave it!

And tell YOUR realtor to bring around more qualified prospects. No Millennials!

-Hal

Sounds like someone lost their chew toy....

JAP>

 

[480sparky]

When I was a helper, one of the first jobs I was given to do on my own was to install one new receptacle in each room, each on its own circuit, for portable heaters.

Installing a 'dedicated' circuit in each room for a heat is easy. Predicting where the future homeowners are going to plug in their heaters.... that's another kettle of fish.

 

[kwired]

I do my best to discourage portable heaters, especially in dwellings in general living spaces. They are fire hazards period.

You can buy one that is expensive, claims to not have any hot exterior surfaces etc, but reality is they still draw ~900-1500 watts, and still seen many of those units that still melt the plug/receptacle connection point if it is not in excellent condition.

You can't compare them to a similar wattage kitchen appliance or even a hair dryer, as those items typically have limited run time compared to a space heater which in some cases might run nearly 24/7 and that poor connection at the receptacle never cools down.

 

[tortuga]

I do my best to discourage portable heaters, especially in dwellings in general living spaces. They are fire hazards period.

You can buy one that is expensive, claims to not have any hot exterior surfaces etc, but reality is they still draw ~900-1500 watts, and still seen many of those units that still melt the plug/receptacle connection point if it is not in excellent condition.

You can't compare them to a similar wattage kitchen appliance or even a hair dryer, as those items typically have limited run time compared to a space heater which in some cases might run nearly 24/7 and that poor connection at the receptacle never cools down.

Agreed I dont even see how the 1500W ones are legal with a 5-15 cord cap, as they are a continuous load.
It would be better if they made a 240V portable heater like they do window AC units.
Then have a single 6-15 or 6-20 receptacle near a window and cover both use cases.

 

[480sparky]

Agreed I dont even see how the 1500W ones are legal with a 5-15 cord cap, as they are a continuous load.....

As long as there's a thermostat in the unit, it's not a continuous load.

 

[gadfly56]

As long as there's a thermostat in the unit, it's not a continuous load.

If the heat loss from the space is greater than the output of the heater, it will be a continuous load. The thermostat will never cut it off.

 

[480sparky]

If the heat loss from the space is greater than the output of the heater, it will be a continuous load. The thermostat will never cut it off.

You could make that claim for just about ANY load. A sump pump could be flooded and the float switch will never turn it off. An oven door left open so the the elements will never turn off. A light switch could get left on.

The NEC definition of a continuous load is "A load where the maximum current is expected to continue for 3 hours or more." Not possible... just expected.


If you go down that road, then every load on the planet will, one way or another, suddenly be considered continuous. You really want that?

 

[electrofelon]

You could make that claim for just about ANY load. A sump pump could be flooded and the float switch will never turn it off. An oven door left open so the the elements will never turn off. A light switch could get left on.

The NEC definition of a continuous load is "A load where the maximum current is expected to continue for 3 hours or more." Not possible... just expected.


If you go down that road, then every load on the planet will, one way or another, suddenly be considered continuous. You really want that?

I get what you are saying, but I really think portable heaters are different. Far more often than not, I see portable electric heaters in situations where the T-stat will never be satisfied. FWIW even article 424 stuff is considered a continuous load, no sure why, even though i is more likely to be larger and appropriately sized for the heating load.

 

[kwired]

I can almost promise that if they started making them put 20 amp cord caps on a 1500 watt space heater that you would find many consumers would cut that factory installed cap off and install a 15 amp cap on it or at least find a handyman that will do it.

 

[LarryFine]

I've seen plug blades twisted 90 degrees.

"Every time someone makes something idiot-proof, they come out with new-and-improved idiots."

 

[tortuga]

Yeah I agree 20A 120V would just get cut off;
however those 1500W heaters dont meet code on a 15A 120V general purpose residential circuit continuious load or not.
Here is my code interpretation:
424.1 states it only applies to fixed electric equipment used for space heating so its out.
A portable heater falls under 422:

422.1 Scope. This article covers electrical appliances used in
any occupancy.

Circuit sizing for this use case is 422.10(B) which just sends you to 210.23 :

(B) Circuits Supplying Two or More Loads. For branch cir-
cuits supplying appliance and other loads, the rating shall be
determined in accordance with 210.23.

210.23 states that

(1) Cord-and-Plug-Connected Equipment Not Fastened in
Place. The rating of any one cord-and-plug-connected utilization
equipment not fastened in place shall not exceed 80 percent of
the branch-circuit ampere rating.

branch-circuit ampere rating =
15A X 120V = 1800W
The rating of any one cord-and-plug-connected utilization
equipment not fastened in place shall not exceed:
1800W X .8 = 1440W.

QED

The 1440W here lines up with us being allowed to use 240V in 210.6:

210.6 Branch-Circuit Voltage Limitations. The nominal volt-
age of branch circuits shall not exceed the values permitted by
210.6(A) through (E).
(A) Occupancy Limitation. In dwelling units and guest rooms
or guest suites of hotels, motels, and similar occupancies, the
voltage shall not exceed 120 volts, nominal, between conductors
that supply the terminals of the following:
...
(2)Cord-and-plug-connected loads 1440 volt-amperes, nominal, or less...

Cord and plug connected loads over 1440 W can be 240V in a dwelling unit, like window AC units commonly are.
The best solution for use of portable heaters ( I love mine in my office) would be 240V 15A over 1440W:

but unfortunately they are not manufactured.

 

[yuhong]

Yeah I agree 20A 120V would just get cut off;
however those 1500W heaters dont meet code on a 15A 120V general purpose residential circuit continuious load or not.
Here is my code interpretation:
424.1 states it only applies to fixed electric equipment used for space heating so its out.
A portable heater falls under 422:

Circuit sizing for this use case is 422.10(B) which just sends you to 210.23 :



210.23 states that
branch-circuit ampere rating =
15A X 120V = 1800W
The rating of any one cord-and-plug-connected utilization
equipment not fastened in place shall not exceed:
1800W X .8 = 1440W.

QED

The 1440W here lines up with us being allowed to use 240V in 210.6:


Cord and plug connected loads over 1440 W can be 240V in a dwelling unit, like window AC units commonly are.
The best solution for use of portable heaters ( I love mine in my office) would be 240V 15A over 1440W:
View attachment 2552250
but unfortunately they are not manufactured.

These are not intended to be exact values. No one cares about a difference of less than one amp. These are also just heating elements so there is no possibilities of problems even when the voltage is too low.

 

[Little Bill]

The OPs question has been answered. Now this train has gone so far off the track it will just have to park and be a museum.