Sporadic light flickering

[ZapHelp]

I am not an electrician but am looking for some advice as to how to fix my sporadic light flickering problem that has come and gone for the year and a half I have lived in my house

I have LED lights throughout the house that generally provided steady lighting, but a few times a day they will quickly flicker once/twice at a time. Over the past couple months they seemed to stop doing this, but the past three days it looks like the problem came back and I want to resolve it once and for all. I don't know if it relevant but want to mention it hasn't really rained for the past week (to potentially rule out any electrical/water related issue).

It occurs throughout the house in every room and even the lights that are connected to outlets. I have a tenant living on a different floor that has their own breaker box, and they claim they have not seen any flickering over the same year and a half. That said, some people who have been in my house have noticed the flickering and others have not (so it's possible my tenant may just not have noticed).

I also had one electrician come by who checked all the connections (light switches, outlets, and subpanel) and they said there was a loose neutral on the subpanel that they tightened. After they did this, the flickering seemed to go away for a few weeks, but then came back.

I had the utility company come by and they did some sort of testing at the main panel and showed me that there was no voltage fluctuation. The also did the same testing at my subpanel and noted the same thing. If I recall correctly, they said that one of the main wires connecting to the busbar was not 100% snug and suggested that could be the problem, but they said it wasn't within their scope of services to fix that.

In case this info is relevant - I have NOT had any of the circuit breakers go off, and I have never had any of my electric items (e.g., TV, computers, washing machine, etc) turn off randomly. It seems to be limited to the lights only.

So what should be my next step? Is the busbar comment from the utility company the likely cause of this and I should call an electrician back in? Is there anything else to consider before calling another electrician back in?

 

[Chivers]

Have you any equipment that consumes high current / loads? Anything on a timer?

 

[ZapHelp]

There is nothing that is turning on that consumes high current/loads or on a timer (as far as I know - there is nothing obvious to me)

 

[Mike Johnson]

Are the lighting circuits two way switching, if so it could be a ghost voltage from the permanent live in the circuit, lights may need a snubber.

 

[Chivers]

Are any LED controlled by a Dimmer? They seem to flicker at tiny fluctuations

 

[ZapHelp]

@Mike Johnson some of the lights are on two way switches but some are not. The flickering occurs in all the rooms regardless of type of switch, but not certain if occurs simultaneously across all rooms since it's so quick

@Chivers I have some lights on dimmers but the flickers occur on both lights with dimmers and lights without dimmers

 

[ZapHelp]

bump - still looking for help

 

[Mike Johnson]

Have you tried a snubber as suggested?

 

[ZapHelp]

Have you tried a snubber as suggested?

I have not yet because in your earlier post you asked if they were two-way switches, but the majority of my lights are one-way switches, and they all flicker. Would using a snubber on the two way switches help with the lights on one way switches as well?

 

[Mike Johnson]

If the connecting cables between switches run close to each other then yes, it could also be that the LED bulbs do not have a good enough quality driver.

 

[Splitty]

This may sound like a bit of a stretch, but the phase that supplies your house may be on the verge of breaking down at the supply/transformer end or someone on the same supply has a welding machine and when they're occasionally welding there may be a current surge and voltage drop causing your lights to flicker sporadically. Its a guess at best but worth getting it investigated if you can. Also, another guess, does someone in your locale have a high powered ham radio set up. When they broadcast they could be emitting a frequency that disturbs your supply. Led lighting, especially cheap lamps and fittings may be prone to interference from that. Just putting ideas out there for you, no real scientific basis here.

 

[mainline]

One way to go would be to have a quality analyser put on the mains for a few days.

 

[pc1966]

I had the utility company come by and they did some sort of testing at the main panel and showed me that there was no voltage fluctuation. The also did the same testing at my subpanel and noted the same thing. If I recall correctly, they said that one of the main wires connecting to the busbar was not 100% snug and suggested that could be the problem, but they said it wasn't within their scope of services to fix that.

Did you get anyone in to check/fix that observation?

It is normal for power companies to only deal with the supply up to the bill metering point, and after that it is the installation owner's responsibility.

Also ask if any electricians around your area have access to a power quality analyser as @mainline suggests, they leave it connected for a few days and then look at the measurements and hopefully something shows up that coincided with your observations.

 

[Rockingit]

This is actually very common and probably nothing to worry about at an electrical level, despite the annoyance. Voltage fluctuations are very common and completely allowable 218v - 253v under regulations. My own lights flicker at ends of the day because we're rural and as other loads on the network come on/off you'll get very minor spikes and drops, the problem is that our eyes are incredibly sensitive to spotting these and also work at a harmonic of 50Hz which doesn't help either. In my last house the lights would religously dim at breakfast and tea-time due to the farmer down the road firing up the milking parlour.

Unless you've got a strobing disco going on, and you say you've had the internal wiring checked, there's little else to be done. The irony is that if you went back to tungsten lamps you'd probably notice it less.

 

[ZapHelp]

This may sound like a bit of a stretch, but the phase that supplies your house may be on the verge of breaking down at the supply/transformer end or someone on the same supply has a welding machine and when they're occasionally welding there may be a current surge and voltage drop causing your lights to flicker sporadically. Its a guess at best but worth getting it investigated if you can. Also, another guess, does someone in your locale have a high powered ham radio set up. When they broadcast they could be emitting a frequency that disturbs your supply. Led lighting, especially cheap lamps and fittings may be prone to interference from that. Just putting ideas out there for you, no real scientific basis here.

Actually yes I do have a welder on my block who does some work in his garage - I guess I would have to see if my lights flicker when he is away on vacation. I have had months without any flickering and I was going to drop the issue altogether but will pay attention to this going forward

 

[ZapHelp]

This is actually very common and probably nothing to worry about at an electrical level, despite the annoyance. Voltage fluctuations are very common and completely allowable 218v - 253v under regulations. My own lights flicker at ends of the day because we're rural and as other loads on the network come on/off you'll get very minor spikes and drops, the problem is that our eyes are incredibly sensitive to spotting these and also work at a harmonic of 50Hz which doesn't help either. In my last house the lights would religously dim at breakfast and tea-time due to the farmer down the road firing up the milking parlour.

Unless you've got a strobing disco going on, and you say you've had the internal wiring checked, there's little else to be done. The irony is that if you went back to tungsten lamps you'd probably notice it less.

Hmm interesting thought about the tungsten lamps. That's basically referring to the incandescent light bulbs right? I might change one of my rooms to these bulbs to see if it flickers when the LED lights flicker in the other rooms

If the flickering had been gone for months, and then came back again (and was not associated with any rain), that would suggest its not an issue with internal wiring right?

 

[ZapHelp]

Did you get anyone in to check/fix that observation?

It is normal for power companies to only deal with the supply up to the bill metering point, and after that it is the installation owner's responsibility.

Also ask if any electricians around your area have access to a power quality analyser as @mainline suggests, they leave it connected for a few days and then look at the measurements and hopefully something shows up that coincided with your observations.

Not yet -- I wanted to check in with this group before I scheduled a different electrician to come over just so I can bring up anything potentially relevant (like the quality analyser you suggest)

 

[pc1966]

Hmm interesting thought about the tungsten lamps. That's basically referring to the incandescent light bulbs right? I might change one of my rooms to these bulbs to see if it flickers when the LED lights flicker in the other rooms

It is not a simple comparison. Filament lamps have a much greater sensitivity to voltage, but are relatively slow to react. LED vary less with voltage but can blink fast and be more noticeable.

However, the long life, low heat damage, and lower running costs of LED make them the best choice in most situations.

If the flickering had been gone for months, and then came back again (and was not associated with any rain), that would suggest its not an issue with internal wiring right?

It is hard to tell. a poor joint somewhere can come and go with temperature or vibration, or it could be a faulty load taking occasional spikes of power. If it goes for long periods it would seem unlikely to be neighbours, etc.

 

[Rockingit]

This is actually very common and probably nothing to worry about at an electrical level, despite the annoyance. Voltage fluctuations are very common and completely allowable 218v - 253v under regulations. My own lights flicker at ends of the day because we're rural and as other loads on the network come on/off you'll get very minor spikes and drops, the problem is that our eyes are incredibly sensitive to spotting these and also work at a harmonic of 50Hz which doesn't help either. In my last house the lights would religously dim at breakfast and tea-time due to the farmer down the road firing up the milking parlour.

Unless you've got a strobing disco going on, and you say you've had the internal wiring checked, there's little else to be done. The irony is that if you went back to tungsten lamps you'd probably notice it less.

@ZapHelp - just realised you're in NYC so my voltage/frequency numbers ^^^ are totally irrelevant to you! However, the principle still stands. You might want to canvass some neighbours to ask if they ever experience the same thing - if it's a supply issue then it will be effecting more than just you.

 

[ZapHelp]

So I have an update - I had purchased some halogen GE light bulbs and put them into the recessed lighting in the office on the 2nd floor. The office is on a different breaker than the living room which still has the LED bulbs (if that matters). It has been a while since we have had significant flickering but it started up again tonight and so I went upstairs while my wife stayed in the living room. Shortly after, she told me that the living room LED bulbs looked like they turned off and on instantaneously - at that same time, I noticed that the halogen bulbs in the office had a slight change in brightness intensity but not something I would have necessarily picked up on if I were not paying attention.

I've had the halogen bulbs for a month now and never saw a true flicker but meanwhile have seen some light flickering in the living room during this month. This was the first time I was able to coordinate watching both at the same time.

Does that provide any clarity into what the problem may potentially be?