Home>Discussions>ELECTRICAL & LIGHTING>Flickering Lights on separate circuits
13 posts / 0 new
Last post
bjdreyer
Flickering Lights on separate circuits

I've seen a couple of other posts on flickering lights, and was hoping someone could confirm my thoughts based on those posts or offer another perspective.

Home was built in 2001, I recently purchased... so I do not know if it "always" did this.
Symptoms:
#1 - I replaced the wall light fixtures (2) in the living room with new ones because it was blowing bulbs every month or so. The new bulbs are standard type bulbs vs. previous low wattage bulbs... no burnouts since, but, now, when the dryer turns on, it causes the lights in the living room to brighten sharply for a split second. (this affects different circuits)

#2 - We have a water feature outside, and when the pump turns on, it causes several lights (doesn't seem like all of them though) to flicker throughout the house. If we turn the pump off, these lights do not flicker, so it is definitely isolated to the pump. (this affected different circuits)

#3 - When running the pressure washer on the rear deck recently (while stripping to re-stain), the voltage at the living room plugs dropped significantly... I know this because I have an A/V protector that has a voltage readout. Voltage would drop on average between 5-8V... (these MAY be the same circuit so I might expect this to be normal).

In the other threads, it was stated that the Utility connections may be the problem. Do you think that may be the case here... are there other potential problem areas?

Thanks,
Bryan

Re: Flickering Lights on separate circuits

Sounds like a loose connection. The first thing I would do is have the utility check their connections it is usually free. if that checks out Have Liscensed electrical contractor check the connections in the panel. The dryer concerns me because they get brighter when it runs have them also check your dyer outlet. let us know what you find. I hope that helps:)

goldhiller
Re: Flickering Lights on separate circuits

Edited to add ....*Most likely a * loose or corroded neutral connection at either...

1- The service neutral connection at the masthead (assuming aerial as opposed to underground entrance) This is generally where such a fault is likely because it is exposed to the weather (rain and wind)

2- Either of the two service neutral connections inside your meter base

3- The service neutral connection inside your service/breaker box

4- Bad/loose neutral connection inside the breaker box on the branch circuit which feeds these lights that flicker

5- Bad neutral connection on that branch circuit inside a shared junction box somewhere farther downstream

The reason the lights get brighter when the dryer or any other 220V appliance is turned on is because the "other" hot-leg is then providing a usable & additional return to ground for the ailing neutral on the lights leg....resulting in more/better voltage.

BigWalt
Re: Flickering Lights on separate circuits

Guys, I have similar problem with my porch light.

Could a missing ground do that?

Few months ago, I post something about bigger electrical box and found ground wire wasn't connect to wall switch [ same switch that operate porch light ]. I replace the switch with wall timer per Canuk's tip and connect the ground source at the switch.

FYI...I haven't remove the porch light fixture to check connection.

goldhiller
Re: Flickering Lights on separate circuits

You've kinda lost me.

*If* I'm following correctly...you're saying that you've switched the ground leg to this light as opposed to the hot leg???

If the light is flickering, the fault could also be inside the light fixture itself...as you mentioned. Might be a corroded connection in there.

One way that *might* work to check out the supply wiring itself with common tools is to disconnect the wiring from the light fixture ...and then hook up an analog meter equipped with alligator clips to the supply wires. Make sure the switch is turned on and then sit and watch the needle. If it twitches, there's a supply problem somewhere. Of course, if the flickering is abundant and often, then this shouldn't take too long or be too taxing. If only once an hour... then bring a chair, a radio and some beer along to assist. ;)

And of course, this *may not* reveal such a fault because you aren't really applying a load to the circuit. Even if it doesn't reveal the problem...you'll still have the pleasure of the beer. :D

Come to think of it...a hammock might be in order along with that brewski rather than a simple chair.

BigWalt
Re: Flickering Lights on separate circuits
goldhiller wrote:

You've kinda lost me.

*If* I'm following correctly...you're saying that you've switched the ground leg to this light as opposed to the hot leg???

If the light is flickering, the fault could also be inside the light fixture itself...as you mentioned. Might be a corroded connection in there.

One way that *might* work to check out the supply wiring itself with common tools is to disconnect the wiring from the light fixture ...and then hook up an analog meter equipped with alligator clips to the supply wires. Make sure the switch is turned on and then sit and watch the needle. If it twitches, there's a supply problem somewhere. Of course, if the flickering is abundant and often, then this shouldn't take too long or be too taxing. If only once an hour... then bring a chair, a radio and some beer along to assist. ;)

Ahhhh.. I meant is when I was replacing the wall switch for automatic timer wall switch.

The ground at the switch wasn't connect at the first place.
I connect the ground when I installed the automatic timer switch..

I just thought maybe the ground at the light fixture isn't connected and it "might" cause the flickering.

Quote:

Come to think of it...a hammock might be in order along with that brewski rather than a simple chair.

Yeah right...I'll be sleeping and missing all the action of flickering show...LOL:D

canuk
Re: Flickering Lights on separate circuits
BigWalt wrote:

I just thought maybe the ground at the light fixture isn't connected and it "might" cause the flickering.

If the ground wasn't connected at the light fixture it wouldn't affect the operation of the light.
In other words ..... the light will work fine without the ground.

It's likely a connection under a wire nut may be loose .... or the bulb itself.

Quote:

Yeah right...I'll be sleeping and missing all the action of flickering show...LOL:D

And ??? :D

BigWalt
Re: Flickering Lights on separate circuits
canuk wrote:

And ??? :D

I can't give you details...it is too XXX rate.:eek: :D

goldhiller
Re: Flickering Lights on separate circuits

Got a plain old porcelain bare-bulb fixture laying around?

Maybe swap that with the existing porch fixture and see if that flickers, too.

Would be easier to detect than watching for a needle twitch on a meter. Easier to spot from the hammock with your eyes closed, too. ;)

Blue RidgeParkway
Re: Flickering Lights on separate circuits
bjdreyer wrote:

I've seen a couple of other posts on flickering lights, and was hoping someone could confirm my thoughts based on those posts or offer another perspective.

Home was built in 2001, I recently purchased... so I do not know if it "always" did this.
Symptoms:
#1 - I replaced the wall light fixtures (2) in the living room with new ones because it was blowing bulbs every month or so. The new bulbs are standard type bulbs vs. previous low wattage bulbs... no burnouts since, but, now, when the dryer turns on, it causes the lights in the living room to brighten sharply for a split second. (this affects different circuits)

#2 - We have a water feature outside, and when the pump turns on, it causes several lights (doesn't seem like all of them though) to flicker throughout the house. If we turn the pump off, these lights do not flicker, so it is definitely isolated to the pump. (this affected different circuits)

#3 - When running the pressure washer on the rear deck recently (while stripping to re-stain), the voltage at the living room plugs dropped significantly... I know this because I have an A/V protector that has a voltage readout. Voltage would drop on average between 5-8V... (these MAY be the same circuit so I might expect this to be normal).

In the other threads, it was stated that the Utility connections may be the problem. Do you think that may be the case here... are there other potential problem areas?

Thanks,
Bryan

bryan do you have an all electric dryer (240v) or a gas dryer?

if you have an electric dryer you might need the electrician to balance your load center because electric dryer uses 240 but also has 120v circuits he might swap which hot lead feeds which side of the circuit. if you have gas dryer that just has 120 plug the other thing might be if you have multi wire circuits other things might need to be checked.

Ravens 53 already mentioned checking connections from the elctric company side and to and in the panel a loose lug or a bad connection can also cause the symptoms you describe.

getting into the areas outside and the main connections to the panel are safety issues usually beyond the skills and equipment available to the DIYer. power company first then electrician. if it is a 240v electric dryer i suggest you unplug it and not use it until you get this checked out.

you might have made a mistake when you wired your ceiling lights (or repeated a mistake made by the previous person) where wiring was reversed this happens a lot with DIYers and the lights appear to work right but are actually being wired backwards or the switch is opening the neutral and not the hot. this could also make the symptoms if the dryer is 240 or if you have multi wire circuits. also your main ground from the panel needs to be checked or meggered mabe. usually when regular light bulbs are too bright it means too much voltage maybe backfeeding on your netural.

JLMCDANIEL
Re: Flickering Lights on separate circuits

Many drop wires to the panel are aluminum, the connections generally need to be re-tightened periodically. It just seems to be the nature of the aluminum.
Jack

Pages

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.