4000 Watt Heater ISSUE

[Ramper]

I have a 4000W heater that came with a NEMA 6-20P. If I install a 6-20 outlet it appears that I am .7 amps over the limit. 4000 watts is 16.66667 amps and that is above the 80% of a 20A circuit. I plan to use 10/2 wire. Would it be better to use a 25A or 30A breaker? Can a 20A plug (6-20) be used on a 25A or 30A circuit?

 

[klassenl]

Welcome to the wonderful world of manufacturers pushing the limit.

 

[pattenp]

It came wired from the manufacturer that way so use it the way it's wired, 20A circuit with #12 wire and a 6-20R outlet. You aren't to use a 20A outlet on a 25/30A circuit. I have a plug-in 240V 20A heater that's 4000W and I have no problems using it on a 20A 240V circuit. Actually my voltage is closer to 250V which makes it closer to 17A.

 

[Bert_]

Actually my voltage is closer to 250V which makes it closer to 16A.

Not how resistive loads work. Higher voltage will result in MORE current and wattage used.

I wouldn't give it a second though running a 4000w heater on a 20A circuit. So what if it is .7A over the allowed 80%, it will never ever cause a problem.

 

[American Locomotive]

Use a 20A breaker with a 6-20 outlet. Use the heater as it is, and don't worry about it. 0.7A extra isn't going to do anything.

 

[David0858]

It may not run that much anyway. I have two oil filed 120v heaters that are supposed to be 1500 watts. Neither is even 1400 watts. I've had both on a Killawatt meter.

 

[pattenp]

Not how resistive loads work. Higher voltage will result in MORE current and wattage used.

I wouldn't give it a second though running a 4000w heater on a 20A circuit. So what if it is .7A over the allowed 80%, it will never ever cause a problem.

Oops.. had my thinking backward, makes it more like 17A.