On Thursday, June 19, 2014 11:17:23 PM UTC-5, nestork wrote:
'Andy[_35_ Wrote:

;3250183']

I have a customer who has some window units installed, but they keep

blowing the breaker(s).



Troll or not, he seems to be asking a legitimate question.



Andy:

Window air conditioning units draw a lot of power when the

compressor motor is starting. That initial power demand only lasts for

a half a second or so while the motor is coming up to speed. Once at

speed, the current draw quickly comes down, but often the fuse will blow

before the compressor gets up to speed.

To prevent the fuse from blowing during the initial power surge,

you need something called a "Slo-Blo" fuse or a "time delay" fuse. This

kind of fuse will allow overcurrent in the wiring for a short time...

enough time for the motor to come up to speed and the current draw to

subside. The overcurrent for such a short time doesn't do any harm to

the wiring at all.



http://highfields-arc.co.uk/construc...iles/fuse1.gif



Slo-Blo fuses are expensive, costing about $5 each. I expect

there's the equivalent of a Slow Blow fuse when it comes to circuit

breakers, but I'm just not familiar enough with circuit breakers to tell

you what to buy.



Also, you ideally want the window air conditioner on it's own dedicated

circuit so that there's nothing else on the circuit that's also drawing

power. To do that, plug the air conditioner unit into the convenience

outlet on the kitchen stove. The two power cables going to a kitchen

stove will handle 50 amps each but the convenience outlets are fused

down to 15 amps each. Unless you've got some other things drawing power

from that same convenience receptacle, then it'll provide a full 15 amps

(or more) to whatever you plug into it.

nestork

Thanks nestork.

The 2 window units draw 7.1 amps each.

Safety is No. 1 for me.

I will not do ANY work that I would not do in my own home.

I worked in a labs and plants for 20+ years and saw a lot of preventable accidents that brought me to tears.

Take care,
Andy