Enclosed bulb hot environment, CFL or LED better - Page 1
Forum section: electronics / general

author: Rick Law
author_rank: Super Contributor
timestamp: April 24, 2021, 09:53:57 pm
content: I have a pair of kitchen ceiling bulbs that goes out rather frequent (~ 6months). I usually write on the bulb's edge the install date. I know the days but the hours on per day varies too much to determine actually length of on-time.The pair of bulbs is enclosed by a single enclosure. The set up is like the attached picture but it issolid glass bowl instead of wire frame. So there is no air circulation at all and it retains the heat too well. Each time I change the bulbs, I can feel the heat.Which one do you think stands up to heat better? LED or CFL? Or is it too manufacturer or brand dependent that it merely too hard to say?Thanks

author: tunk
author_rank: Super Contributor
timestamp: April 24, 2021, 10:16:09 pm
content: Maybe you could get some high wattage LED bulbs and see if you can derate them:

author: Cerebus
author_rank: Super Contributor
timestamp: April 24, 2021, 10:22:33 pm
content: I have no idea about the theoretical elevated temperature vs life performance of one versus the other. However, the LED lamp is going to pump a lot less heat into the enclosure in the first place and I suspect that will be the bigger influence.Anecdotally, every single LED lamp I have in the house is the first one put in its fixing and their life span so far is as much as seven years with no failures so far. I have an LED lamp in fitting not dissimilar to yours - fully enclosed but with a plastic versus your glass cover - it has lasted 3-4 years so far.

author: Nusa
author_rank: Super Contributor
timestamp: April 24, 2021, 10:33:29 pm
content: Buy LED bulbs that are 'Enclosed Rated'. Yes, that's a real thing marked on the outside of the box. Home Depot even has a filter for it, although I'd double-check the description/box image before buying.I went through several bulbs in my porch light before I figured this out.

author: schmitt trigger
author_rank: Super Contributor
timestamp: April 24, 2021, 10:41:23 pm
content: I believe I have mentioned this earlier;I have had a similar situation, down here the summers are long and very warm.My solution was to use a higher than required wattage lamp which is dimmable. Then with a simple dimmer set it up permanently to about 70% of full electrical power. (Measured)This way the lamp runs significantly cooler, which should help its lifetime.

author: amyk
author_rank: Super Contributor
timestamp: April 25, 2021, 02:29:31 am
content: Check the power quality - transients and sustained overvoltage might be suspected. 6 months is much too short even for the cheap stuff.

author: BrianHG
author_rank: Super Contributor
timestamp: April 25, 2021, 03:08:12 am
content: Quote from: tunk on April 24, 2021, 10:16:09 pmPlease do not do this, especially in the US. God forbid you have a fire, and even though it may not be due to the change you made to a light-bulb's circuitry, if your insurance provider finds out, you will not receive a dime.

author: WattsThat
author_rank: Frequent Contributor
timestamp: April 25, 2021, 03:20:06 am
content: Anecdotal evidence only but for what it’s worth:My house has a total of 38 ceiling fixtures that were originally designed for 75W incandescent R30 reflector floods. All are on dimmers. While not enclosed, the fixtures are not vented.The CFL’s were dimmer rated and would fail in a year or less due to the heat buildup, the bases of units were always brown. They were so bad that in the primary spaces, I kept the incandescents due to the failure rate.Once LED lamp prices dropped below $20 each, I started replacing the incandescents. The replacements are a mix of expensive Phillips lamps going back about eight years and the newest are the cheap Feit brand that are about four years old. Zero failures to date. No brown bases.

author: Rick Law
author_rank: Super Contributor
timestamp: April 25, 2021, 07:29:23 pm
content: Quote from: Cerebus on April 24, 2021, 10:22:33 pmI am of the same mind... That they are lower wattage nominally should by itself has an impact. The CFL's perceived lumens seem to drop fairly fast. I could use a 480lm (40 watts) instead of a pair of 600lm (14Quote from: amyk on April 25, 2021, 02:29:31 amAn over-volt did not occur to me at all. Interesting.So far, all my other stuff survived well. But this gives me another reason to upgrade my DMM (currently UT61E). Use the UT61E for long-term logging and find myself a nicer DMM upgrade... I've been thinking about a nice 6.5 digit DMM... My fingers have been itching on the "Buy Now" button for a while.I should go watch a DVD to cool my fingers a bit before I am a few hundred dollars poorer. Being so close to a PC with working internet connection is financially dangerous to me right now...

author: floobydust
author_rank: Super Contributor
timestamp: April 25, 2021, 10:25:56 pm
content: I've found those light fixtures generally terrible for CFL and LED bulb lifetime. There is a reflective disk, insulator and glass dome - so there is only a tiny amount of convection cooling inside.So far, I'm only having luck withIkea LED bulbsin them. Under $1 each on sale but blah warm white only. Everything else was lucky to last a year.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 25, 2021, 10:43:57 pm
content: I feel like complaining about those corn cob LEDs sold as "microwave oven" bulbs for over-the-range models.The bulbs are not only enclosed, but subject to extra heat and humidity from my sausages.They don't last a year. They're brighter than incandescent bulbs but much more expensive.I wonder why there can't be a reliable solution for this application. I hope new ovens have LEDs form the factory, because that little trap door arrangement SUCKS.

author: james_s
author_rank: Super Contributor
timestamp: April 25, 2021, 11:50:41 pm
content: Quote from: Rick Law on April 25, 2021, 07:29:23 pmThe lumen output depreciates pretty significantly in the first 100 hours, prior to which a reputable one should be producing more than the rated lumens. After that initial period they settle in and the output declines over a much more gradual curve.

author: joseph nicholas
author_rank: Frequent Contributor
timestamp: April 26, 2021, 12:28:51 pm
content: You did not mention if the original bulbs were the same as the proposed replacements.

author: Rick Law
author_rank: Super Contributor
timestamp: April 28, 2021, 01:36:29 am
content: Quote from: joseph nicholas on April 26, 2021, 12:28:51 pmI am currently on CFLs. Attempted LEDs once about 3-5 years ago - they lost lumens rather quick. When they went kaput I switched back to the CFL since.Next round, I am going to switch to LEDs again hoping changes in the last 3-5 years made them better. I am equipped with a lux meter these days, I will fix a "consistent way" to measure so I have an objective gauge rather than subjective recalled perceptions.

author: james_s
author_rank: Super Contributor
timestamp: April 28, 2021, 04:40:01 am
content: Quote from: Rick Law on April 28, 2021, 01:36:29 amLook for some that are rated for use in enclosed fixtures. Lumen depreciation should be negligible on a good LED bulb. About a year ago I took the Philips LED bulb that I installed in my porch light in 2011 and tried it side by side with a NOS identical lamp that never got used, they were indistinguishable. That porch light runs dusk till dawn 7 days a week, average around 12 hours a night.

author: Rick Law
author_rank: Super Contributor
timestamp: April 28, 2021, 06:49:45 am
content: Quote from: james_s on April 28, 2021, 04:40:01 amActually, I did look at my local home depot for that. They didn't have them. I was there shopping for a run of the mill toilet tank inlet hose, they didn't have that either. I'll have to hunt again later.It could be because of the spring time (gardening needs and people like myself fixing things up after the winter); adding to that we are still in semi-lock down.Irony, while people are home with time on their hands to fix various things, the tools and parts are hard to get...

author: james_s
author_rank: Super Contributor
timestamp: April 28, 2021, 08:39:44 pm
content: Quote from: Rick Law on April 28, 2021, 06:49:45 amThere are some supply line disruptions still but I suspect a lot of it is exactly what you say, a lot of people are home, the ones who are working from home have a lot of time they aren't spending commuting and have motivation to do projects that make it easier for them to work at home, this leads to shortages. Things like closet shelving parts have been pretty well picked over every time I've been to the local big box home center.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 29, 2021, 01:44:29 am
content: Have you considered a wall wart (rated to twice the current you actually need) plugged into the light socket using an adapter powering some LED strips?

author: Rick Law
author_rank: Super Contributor
timestamp: April 29, 2021, 05:53:40 pm
content: Quote from: NiHaoMike on April 29, 2021, 01:44:29 amYes I have - in fact, I got a pair of the LED strips already (240 per strip @ about 900mA), but wife didn't like the idea of having strips on the wall. I could keeping them in the bowl but the dots of bright randomly placed inside the bowl looked awkward.So, I have a pair of strips unused. As soon as I get around to it, I plan to make a few long alligator clip cords to use the pair as emergency light with my car's jump-booster as power source.Quote from: amyk on April 25, 2021, 02:29:31 amAfter see this post, I was more alert. An infrequent slight blinking my lights a caught my attention (twice, sub-second off then back on).I know this happened before, frequent enough for me to remember but I never put much thought to it thinking it may be wind-caused tree branches brushing the power line. We do have frequent (once a year or so) high-wind caused outages.I have to pay more attention to such quick-blink from now on. The in-coming power may be less reliable than I thought.

author: Zero999
author_rank: Super Contributor
timestamp: April 29, 2021, 08:21:37 pm
content: Quote from: BrianHG on April 25, 2021, 03:08:12 amI appreciate that's a pretty standard disclaimer, but did you watch the video? The hack is trivial: just remove a resistor. Since the all the components will be running at a much lower temperature, after the hack, it will theoretically reduce the risk of fire. The only thing you need to be careful of is to securely put it back together again, to eliminate the risk of shock. If there is a fire, how are they going to know the bulb was modified? It's highly unlikely they'll even look at it, unless the fire has clearly originated from the bulb, which is less likely, than if it were unmodified. There are risks with everything and this is one which I think is worth taking

author: Sal Ammoniac
author_rank: Super Contributor
timestamp: April 29, 2021, 09:39:45 pm
content: +1 on using bulbs rated for enclosed use. I have four LED bulbs in my porch lights and they've been lit 24/7 since 2010 and none have failed.

author: Rick Law
author_rank: Super Contributor
timestamp: April 30, 2021, 09:14:31 pm
content: Quote from: Rick Law on April 29, 2021, 05:53:40 pmRant, rant...Speak of the devil ... high wind today, second outage today already... The third day this year (with multiple high-wind outage) already, and it is only April!Hopefully, it did not add more to my repair to-do list as I am not done with what is on it yet. Last time it blew one of my mirrored drive out and I am still on "reduced mirror" mirroring on a now non-existing drive.I was working on my C project, today was to be polishing and deploy. This morning's work is a total lost. I was just an hour into recover my morning work, and it hit again. Now I am totally off my track, forgetting which part was recovered and which was not. Good that I have an SOD (start of day) backup.I'm going to watch TV and eat something... I'll have start over today's work after I wait till the wind dies down.Yeah, my local power is not as reliable as I like to think...

author: james_s
author_rank: Super Contributor
timestamp: April 30, 2021, 10:58:16 pm
content: Quote from: Rick Law on April 30, 2021, 09:14:31 pmSounds like you need a UPS. Outages are rare here but glitches during windy winter days are not uncommon. I have most of my important stuff on UPS's, along with a couple of the lamps in my living room, it's an easy way of eliminating nuisance restarts of all sorts of equipment.

author: Rick Law
author_rank: Super Contributor
timestamp: May 01, 2021, 11:46:41 pm
content: Quote from: james_s on April 30, 2021, 10:58:16 pmI used to have one... As I add additional HDD's to the server, I exceeded the power capability of my old UPS and killed it outright (or may be just the fuse). Those are some of the things I need to address... eventually.

author: drussell
author_rank: Super Contributor
timestamp: May 02, 2021, 05:35:46 pm
content: Quote from: Rick Law on April 29, 2021, 05:53:40 pmEven if your incoming power is relatively stable, it is rather common for the $0.59 light switch in the wall to make poor contact and make lights flicker, even burning out incandescent bulbs much sooner than "normal". Anywhere that you have poor lifetime on any sort of bulb, especially if you notice any flicker, consider changing the wall switch for good measure.That reminds me, I need to change the one in my bathroom, it's been starting to noticeably flicker sometimes (easily verified in this case by wiggling the toggle a bit to see that it's not always making a good connection) and it has burned out a couple bulbs fairly rapidly. I've just been too lazy to actually change it and yet always try to sort of forcefully turn it on to make sure it connects well. Which is dumb, because I already have new switches on hand, probably at least a couple 10-packs of them, and I've already wasted more light-bulb-lifetime-dollars than the <$1 switch.I guess I really should change the damn switch. It would take me 2 minutes...

author: james_s
author_rank: Super Contributor
timestamp: May 02, 2021, 08:39:11 pm
content: Interesting, I don't recall ever having a light switch fail, except for a case where one got physically damaged by moving a large piece of furniture. For just a few dollars you can get nice heavy duty spec grade switches as used in commercial buildings, they're much sturdier and feel nicer so I usually use those.

author: Rick Law
author_rank: Super Contributor
timestamp: May 02, 2021, 09:13:58 pm
content: Quote from: drussell on May 02, 2021, 05:35:46 pmAnother thing that I didn't consider (even as I am struggling with my flash light switch now and again)...Starting this thread is a lot more beneficial than I thought. This is good - I am more alert of these now.