Too many amps??

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kickflip_mj

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so quick question i have a 1500w 120v element controlled by a pid with a computer fan on the same circut.now my question is is if i hooked a march 809 pump to the same circut would i pop my 15 amp breaker. i have 50' of 14awg
 
First off a 1500 watt element will draw 12.5 amps, call the computer fan another .25 amps (guessing). For a 15 amp breaker operating at 80% by code your already at 12 amps vs 12.75 your loaded down. This without adding the March pumps starting current and running amperage of app .25 amp draw. Your now at 13 amps minimum or 86.6% (80% legal). Now you add 50' of 14 gauge extension cord there's another bug in the ointment, another 50' of useless heating element. A weak or hammered breaker can tip below its amperage rating. I would draw power off a 20 amp breaker and plug (not a 15 amp plug), fed with #12 gauge cord minimum and keep the cord length at the minimum length.
Sounds like your "power (wattage) limited", this sucks. To have an all electric brewing system heating included should require 230 volts to speed up your heating times.
I know this is not not the answers your wishing for right?
 
well right now i was running the element off a 15 amp breaker and didnt have a problem... are you saying that without the pump im ok? i wanted to run it of a gfci in my bathroom of my appartment, i dont think anything in my place has a 20 amp.. but im not at my appt curently
 
The 1500 watt heater will draw about 12.5 amps and the March pump is rated at 1.5 amps for a total of 14 amps, which is just under the nominal 15 amp rating of the breaker. However, you typically oversize the circuit by 20%, to account for various things including variation in the actual trip point of the breaker, so the 1500 watts for the element becomes 1750 watts or 15 amps, which about the max load you should put on the 15 amp circuit. (Ever notice that 1500 watts is the maximum wattage hairdryer that you can find). So even though the breaker might not pop with the pump is running, it should probably be on it's own circuit.

The 50' of 14 awg just adds resistance to the circuit which will reduce the amount of current flowing and therefore will reduce the likelihood of the breaker popping.

Paul
 
well thanks guys, i will probably just make its own circut then for the pump....it will make life a whole heck of alot easier. thanks again
michael
 
The 50' of 14 awg just adds resistance to the circuit which will reduce the amount of current flowing and therefore will reduce the likelihood of the breaker popping.

Paul

That long cord length resistance will also reduce the elements current reducing your 1500 watts heating element to a lower available wattage output. Feel the cord after 15 minutes running, bet it will be warm to the touch. I would do a dry run with water first.
 
FYI

I didn't do any formal calculations but I run my 1500W element, pump and love control all on one 50' cord with no circuit issues. Since I have an element in my HLT and one in my MLT, I use one 20 amp circuit and one 15 amp circuit in my garage with no issues either way.

Of course every house will be different.

Linc
 
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