Lights dim when washer kicks on

[bochnak]

I bought my home with the basement washer and dryer sharing another circuit on the 1st floor. The bathroom lights would dim when washer kicked in. I don’t know if they shared the same circuit.

Fast forward to this weekend, where I moved the washer/dryer into a new laundry room. They are now on a separate circuit. Bathroom lights still dim when washer kicks in.

What gives?

Just curious since I eventually will have some higher current use stuff in the garage. I don’t want lights to dim in the house when I’m out in the garage goofing around.

Home main panel is 100A pushmatic. I have a 60A breaker feeding the garage sub.

 

[nehog]

It could be a problem in several places, the main breaker, the feed to the house, the box, or bad wiring...

This is one where I'd recommend an electrician give you a hand.

 

[fflintstone]

I used to have an old house with a 60A service coming in. the wiring was all a mish mash of old and new wiring. And then all the stuff I added. The funny thing was the previous owner had #2 wire feeding the garage, but no 240V outlets. When I would start welding the lights in the house would dim. No way around it without upgrading the service. Lived with it for 15 years, now it is someone else’s problem.
Dimming is a sign of a large load starting. Your washer may be going bad and pulling a lot of amps to start. If it is only the bathroom lights, you may have a poor ground on that circuit.

 

[trythis]

I just replaced a washing machine that caused the same problem. I didn't even remember it doing that until I saw this thread. I have a 2 year old electric service and was surprised that it did that when my 5HP planer (farm duty 5 capacitor motor) didn't cause the lights to dim. Anyway, the new machine doesn't cause the slightest shimmer in the lights.
Maybe it is your machine. Does anything else cause this?

 

[2LTim]

It is possible that your bath light is the only "light" circuit on that side of your panel. Not likely, but possible. Swap the breaker that runs the washer with the one on either side of it (up or down that side of the panel). This will move it to the other leg of your service. Now see if you have any other lights that dim when it starts. If by chance your bath light still dims (or others for that matter) it is time for some serious voltage drop testing.

 

[hillbilly1]

It can also be on the utility side, I don't know where you are located, but up north the utilities would run several houses off one small transformer. This worked fine back in the 60's when the loads were light, but nowadays we have A/C units, microwaves and other large power eating appliances. My cousin had a 5 HP air compressor in his shop, and while it was running all of the neighbor's lights would blink!

 

[mrb]

I just replaced a washing machine that caused the same problem. I didn't even remember it doing that until I saw this thread. I have a 2 year old electric service and was surprised that it did that when my 5HP planer (farm duty 5 capacitor motor) didn't cause the lights to dim. Anyway, the new machine doesn't cause the slightest shimmer in the lights.
Maybe it is your machine. Does anything else cause this?

the older washing machines just had a motor that was switched on and off. the new ones use an inverter to drive a synchronous dc or 3ph motor, -motor doesnt draw alot of current on startup due to the soft start nature of the controller.

 

[bochnak]

My washer is 4 years old.

I'll do a little more troubleshooting to answer some of your Q's.

 

[CraigFL]

It could be a capacitor start motor with a failing capacitor causing abnormally high starting current.

 

[Sawbladz]

Yup, time to check the draw at startup of your washer.

 

[MrMark]

How badly do they dim? Some dimming is unavoidable with high inrush current motors.

If the dimming is excessive it is probably the neutral connection at the panel. That is the first place to check to see that it is solid, tight, and corrosion free.

 

[Falcon67]

 

[rodm1]

How badly do they dim? Some dimming is unavoidable with high inrush current motors.

If the dimming is excessive it is probably the neutral connection at the panel. That is the first place to check to see that it is solid, tight, and corrosion free.

 

[bochnak]

How badly do they dim? Some dimming is unavoidable with high inrush current motors.

If the dimming is excessive it is probably the neutral connection at the panel. That is the first place to check to see that it is solid, tight, and corrosion free.

Dimming is not bad.....and only for a split second.

I will check all neutral connections. Thanks

 

[bochnak]

LOL....no thanks.

 

[jwillis]

I think some older appliances just draw a lot of amps and cause the lights in a home to dim. My sump pump in my basement has always done the same thing. The lights in the whole house dim and they have done this forever. I had a neighbor who had the same problem and he upgraded from 100 amp service to 200 amp service and his sump pump still dimmed his lights. I have three sump pumps, two for backups and the one that is only been used for about a year still dims my lights. Of course I have an older service. Running my table saw in my shop dims the lights. I grew up in this house and have lived here since 1951. So after 60 years, I don't really worry about it. Except when I have to go all the way down to the basement and reset the breaker because it kicked out when I flushed the toilet.

 

[jwillis]

Oops!! I just hit the "Post Quick Reply" below button on my computer to post that last message and there they went again.