Why are the lights dimming in the kitchen when the Fridge kicks on?

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mgotgame

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I am a new electrician, still in my first year @ apprenticeship school, and I have a word-order to look @ on Monday regarding a homeowner's kitchen lights getting dim whenever his Refridgerator kicks on. I don't know what to look for or even how to fix this. Any help at all would be appreciated. Thank you, Mgotgame
 
mgotgame said:
a homeowner's kitchen lights getting dim whenever his Refridgerator kicks on. Mgotgame
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This usually predicts a loose or corroded neutral (grounded circuit conductor)
If the service is aluminum (pre 8000 series) it may indicate creepage at a terminal.

in short you may need to either clean or tighten the grounded circuit connections at the panel, J-box or loop wired devices. I had a problem once where the neutral on the aerial service drop was corroded the poco replaced the drop and solved the problem.
 
I'd say they are probably on the same circuit and the Locked Rotor Amps from the fridge compressor are causing the momentary dimming. If that's the case, try to put the fridge on a separate circuit as I always do in new construction.
 
Not trying to put you down guy, but why are they sending a pretty much green helper on a service call like this????? As stated the problem is more than likely that they are on the same circuit.Which was pretty common back in the day.If so the only remedy is to retro fit a dedicated circuit for the fridge.
 
Members we have no idea what the rules are where mgotgame is working.

If you have nothing to add about the dimming lights than please at least let mgotgame respond before you gang up on mgotgame about what his boss has him doing.
 
Always start with the question of when this all started.Was anything new added or any other repairs.Perhaps he just bought this house and its new to him.Service work is not easy even after you have many years in trade.One sure fix if the neutral is not at fault is add a dedicated circuit for this frig.
 
Just to clarify, I am going to the house with a qualified journeyman, I am just his apprentice, it is a new construction house, and the home-owner just moved in and his house is under a 1-year warranty for any type of service work on the house...I am trying to get a jump start on the situation and familiarize myself with all the different solutions people can offer. I am trying to educate myself a little bit more, so that when we go there I will have a better understanding of the situation before we get started, Thanks again for anyone who has helped and I will be checking back on this all weekend!
 
I'm glad you have a journeyman going with you. I also think its good that you are eadger to learn and help. That's a good sign for your future as an electrician.

Basically, the refrigerator draws a lot of current when the compressor motor starts. This causes a voltage drop along the relatively small wire feeding the receptacle. If lights are on the same circuit, they also see this voltage drop. That shows up as the lights dimming (for a second, they only get 100 volts instead of 120v.)

If the fridge is on a different ciircuit, then it is either drawing enough current to cause a voltage drop on the main feeder wires and the service conductors, or it might be a loose connection like CPAL mentioned.

If you have a code book, look at 210.11(C)(1) and 210.52(C)(1). That says you need at least 2 branch circuits in the kitchen to run receptacles. It also limits what else you can put on these circuits (no lights are allowed). It also says the refrig can be on one of these 2 circuits, or it can have it's own circuit.

Steve
 
If there is time to spare why not ask him to let you try to find it first.The lights should not be on this circuit but one never knows what might have got messed up.I would start in the panel with checking all connections.Good luck.
 
Good job getting involved w/ these forums so early on. I've been in this 8 yrs and just now found out about them. Make sure the customer realizes the potential cost of the troubleshooting, as this "dimming" might not be anything you don't find in any older home. If it is bad, some of the ideas the other guys gave are good; also, as a potentially quick solution, I've had luck a few times by simply tightening all the terminals on the neutral bar in the panel. Might not be the hi-tech answer you were looking for, but i've got lucky a few times by simply trying that first.
 
The issue with the lights may be a fundamental problem of unbalanced voltage across the line to neutral loads


http://www.tlc-direct.co.uk/Book/5.6.3.htm

there are many pages and text that deal with this concept in fact most standardized tests will present questions to determine a applicants understanding of such conditions.

Also as mentioned it could be an overloadon the individual circuit with a heavy load.

motors such as the refridgerator will draw a minimum of 6 times its operating current when starting (rule of thumb) the refridge motor will draw more especially if the pressure in the colling lines is unequal ( not as common as the lod stuff).

If you draw a large current on a circuit the line will experince a loss of voltage from the point of origin to the point of load. "current of the line times resistance of the line" E=I.R (voltage drop). If the voltage dips the incandescent light will dim.


IMO
 
First, it's a warrantee call on a new home, so I'd start with finding the original prints for wiring that kitchen and making sure someone didn't put a dashed line between the fridge outlet and the lights. Then I'd find the breaker for the fridge, turn it off, and see what else is off. I'd wager $0.05 that the kitchen lights turn off at the same time ...
 
mgotgame said:
I am a new electrician, still in my first year @ apprenticeship school, and I have a word-order to look @ on Monday regarding a homeowner's kitchen lights getting dim whenever his Refridgerator kicks on. I don't know what to look for or even how to fix this. Any help at all would be appreciated. Thank you, Mgotgame
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I am assuming you mean dim and get bright within a second and not staying dim.
There are tons of things you can try. First is what others have offered already-- go to the panel and tighten everything down. Open the receptacle at the Refrig and make sure all terminals are tight. The third thing to try is an extension cord, preferrably 12 gauge and plug the refrig into different circuits and see if the dimming is still happening. I would also see if the A/C is causing the lights to dim. If it is just the kitchen lights that are dimming then you may have a loose connection in any of the junction box that are tied into the lighting circuit. Good luck..
 
One never knows what might have happened or was done to get around a left out wire.Would be good idea to start with turning the fridge breaker off.And if them lights go out with it your in for a bad day.
 
I'm in the group that says it is a loose connection in the panel. I doupt that a one year old home has been wired with the fridge on a circuit with the lights unless the fridge in question is a second fridge pluged in to a rec that was easier to hit with the lighting circuit. (seen this) and I also think you should ask your lead guy to let you take a stab at it first and give you hints as you find things. I am a start at the panel guy. how many times the homeowner has told me the breaker was on and it was not...too many. one guy said to me as he wrote the check for the service call, "Well school cost money." so I always start at the panel and go from there. loose connections are common after a year the guy doing the panel can leave a wire not tightened all the way pretty easy. But since this is most likely on your bosses dime don't waste time if your lead guy sees something quick get it fixed and get on your way.
 
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