Flourescent light weak at start up in cold weather?

[BigE]

I have an eight foot flourescent light in my garage. It was there when I bought the house and was obviously installed after construction to replace a single, incandescent fixture in the middle of the garage (approx. 20x22, residential 2 car garage). The garage is on the end of the house, but I have a sneaking suspicion that the 3 walls not connected to the house are uninsulated. So when it's cold outside, it's pretty much cold in the garage. If I go out and flip the switch to turn on the flourescent light, it immediately fires off, but it is very dim. It's still enough to light the way, but not as bright as when the light has been on for several minutes. Do your flourescent lights react this way? Have you noticed decreased bulb life as a result?

Also, to add to the description, I leave my garage door open a lot while I'm at home. Not as much in the winter though as I have an aversion to freezing.

 

[nate379]

That's normal.

 

[Sokoloff]

There are cold weather ballasts available which reduce (but don't eliminate) this issue. If you don't find it especially annoying, I'd just leave it. It won't hurt anything.

 

[Nostraquedeo]

The light output and performance of fluorescent lamps is critically affected by the temperature of the bulb wall and its effect on the partial pressure of mercury vapor within the lamp. Each lamp contains a small amount of mercury, which must vaporize to support the lamp current and generate light. At low temperatures the mercury is in the form of dispersed liquid droplets. As the lamp warms, more of the mercury is in vapor form producing more light. I would just be patient and give the lamp the one or two minutes it needs to warm up. As mentioned they make ballasts rated for cooler temps.

 

[BigE]

I'm in Alabama so my definition of cooler temps probably doesn't match theirs. It probably wouldn't be worth it. I'm going to reskin my garage this spring anyway so I'll be adding insulation and more/better lighting. I'll just leave it as is. Thanks for the replies.

 

[jmh21586]

how much mercury is actually in an 8' bulb anyway??

 

[Gary S]

how much mercury is actually in an 8' bulb anyway??

Probably enough to kill a small labatory rat if he ate it all.

 

[Keith_MN]

That is why I installed both incandescents and fluorescents in my garage. If I am not going to be there long, I just run the incandescents, when I am working in there I usually run both.

 

[Falcon67]

I'm replacing all my old lights and ballasts with electronic units to get away from that issue.

 

[Gary S]

I'm replacing all my old lights and ballasts with electronic units to get away from that issue.

I already did that. My indoor garage florescent lights are all 0˚F lights. My outdoor florescent are all -20˚F lights. They all work all the time. Once you get the right florescent lights you will wonder why you ever used incandescent, mercury vapor, or high pressure sodium.

 

[jmh21586]

Probably enough to kill a small labatory rat if he ate it all.

I always assumed the hype was worse than the bite.

 

[torqueman2002]

I already did that. My indoor garage florescent lights are all 0˚F lights...

I live in SE Michigan where the temp. in my attached garage can get below freezing; so, I'm having the same slow to warm up problem with the fluorescent lights.

I searched on 'low temperature fluorescent lights' on Amazon and Google, without much luck.

What brand/model are you using in your garage, and could you recommend a supplier?

Thanks.

Mike

 

[Charles (in GA)]

I have 8 ft two tube strips over my workbenches. In the cold they are dim and you can see "waves" running from one end to the other. Depending on how cold it is, they may never warm up enough for the "waves" to go away. I just grin and bear it, as, if its that cold in the shop, I won't be working out there.

Charles

 

[Gary S]

Mine have the "waves" in them for the first couple of minutes too during warm up, but it goes away fast and they then come up to full brightness. I've tested the indoor ones down to about 15˚F and I'm happy with them.
Mine are just the cheap 4' fixtures from Menards with T8 lamps in them. I don't know the brand.
My outdoor ones are rated at -20˚F and they live up to their rating. They are on photocells and I've had winter evenings when the temp was already at -20˚F at dark. They light somewhat slow, but haven't failed me yet. At dusk you can't really tell how bright they are anyway, and long before it is totally dark they are up to full brightness. These are Cooper brand lights.

 

[jmh21586]

Whats the big deal about waiting a couple minutes for the lights to warm up anyway?

 

[Gary S]

Whats the big deal about waiting a couple minutes for the lights to warm up anyway?

I don't have a problem with it. Even starting up, my florescents put out better light than the incandescents I had there before. And after a couple of minutes of warmup they really put out the light.

 

[Wow]

how much mercury is actually in an 8' bulb anyway??

About 7mg.

You can get tubes that are designed for cold weather too, just like cold weather ballasts. The Philips Alto 8' tubes I have claim to be very good for "cold storage" in their spec sheet. They flicker a bit when starting due to the magnetic ballasts, but, they "warm up" to pretty much full brightness within seconds, when it's only 35 in the shop.

I have some of the same 8' fixtures in my barn, with cheap unbranded tubes. They dim and flicker like crazy when it's cold.

 

[dugger10]

To prevent the slow start in cold weather replace the fixture with an "HO" type, stands for high output. They are design to work in cold weather and high ceiling applications. Another type is "VHO", very high output. These are used in outdoor signs exposed to cold weather. They are not cheap however, Lowes and Home DEpot sell them, about 60 bucks a fixture then about 5 bucks a buld. The advange is no prematuer loss of ballast great light, very bright. I have used these in three of my last shops and installed hundreds in storerooms and barns. In my own shop I have only replace two bulds after years of use. Also remember that every light buld has a rated number of hours it will burn Floursants are no different except they ussually don't just quite burning, they slowely put out less and less light. This is very hard on the ballast and causes them to go out if continued to be on with bulds past their life. The other great benifit is you can use less HO fixtures and have much more light so the cost is somewhat higher on the front end but way cheaper during the life of the fixture which can be years. I used 4 eight ft. 2 bulds fixtures in a 30 x 20 with 10 ft. ceilings. Sorry this was so long and I hope it helps. O and they start way better in cold weather that regular floursants.

 

[dugger10]

And that was a 30 x 30 building.

 

[jmh21586]

I have 9 of those 8', two bulb HO fixtures in my 30x30.

 

[trythis]

I researched this a while. You need to find what sort of bulbs you have, F96T8 HO or F96T12N/120 or 277... for voltage
There are a lot of different tubes. The sockets for the tubes are not interchangeable.
F fluorescent 96 is the length of the bulb T8 or T12 or T5 is the diameter. HO High output, N normal.


Figure out your tube requirements, plug that into google. Dig through page after page looking for model numbers from companies that sell the ballasts. Plug model numbers in until you find specs that you are looking for. Then find the cheapest price for the one that works

Home depot has pretty good prices on ballasts. I buy F96T12HO prolines by GE cheapest there... Work any temp I have seen this winter, thought the lights aren't as bright.

Sometimes the ballasts are more expensive than new fixtures! You have to check the ballasts that come with the new fixtures though. They can be pretty crappy.

 

[dugger10]

Sounds like BS to me, buy HO's from Lowes or Home Depot unless you got a source and your good for years. Seems silly to me what he posted but thats just my opion.