Was at home depo shopping for an f18t8 lamp in cool white but only found them in f17t8. Are they the same spec?

The spec's are different, but they should run just fine (atleast that was my experiance...)

The spec's are different, but they should run just fine (atleast that was my experiance...)

Ok i have an electronic f18 ballast that will work better i assume then magnetic, i also have a detecated f17, f25, and f32 ballast but that is a 4 lamper.

It's an electronic ballast for F18T8?  Do you have a picture?  Most F18T8 ballasts in the U.S. at least were preheat.  In fact your typical 14-20W preheat choke works just fine for F18T8.  When operating an F17T8 on preheat the lower voltage cathodes may not be heated adequately resulting in sputtering, but yes, they'll still work.  You might be able to find cool white in stores, but even those aren't common.  Lowes used to carry them but I believe they dropped them a year or two ago.  Menards still stocked them at some point.  I don't recall seeing them at Home Depot. 

You can order them, however.  Lightbulbs.com for instance has a decent selection of white 18W T8s, plus some colors as well.

It's an electronic ballast for F18T8?  Do you have a picture?  Most F18T8 ballasts in the U.S. at least were preheat.  In fact your typical 14-20W preheat choke works just fine for F18T8.  When operating an F17T8 on preheat the lower voltage cathodes may not be heated adequately resulting in sputtering, but yes, they'll still work.  You might be able to find cool white in stores, but even those aren't common.  Lowes used to carry them but I believe they dropped them a year or two ago.  Menards still stocked them at some point.  I don't recall seeing them at Home Depot. 

You can order them, however.  Lightbulbs.com for instance has a decent selection of white 18W T8s, plus some colors as well.

My ballast is IS so i don't think the cathode issue would be a problem. The light i got used an electronic ballast for hum free instant on, shame preheat isnt as common as it used to be. I will probably not order it on the account of me not having the ability to do to being in highschool.

I wonder how the electronic would drive an 18W T8.  It's possible it'll overdrive it a bit.  I'm not sure.  It's an odd ballast choice though.  Why would the manufacturer go to an electronic ballast, but not switch to 17W?  It'd make sense if the 18W was more common, but it's not and never was widely used in North America.

I wonder how the electronic would drive an 18W T8.  It's possible it'll overdrive it a bit.  I'm not sure.  It's an odd ballast choice though.  Why would the manufacturer go to an electronic ballast, but not switch to 17W?  It'd make sense if the 18W was more common, but it's not and never was widely used in North America.

I think the lights they had where preheat, but swapped over to Electronic as its now cheaper to make a pcb then an iron lump and a neon glow bottle Maybe they just kept it f18t8? It is the 24 inch verion of the lamp, i dont knwo why they did it

Is that ballast in a plant or aquarium fixture by chance?
F18T8 is not uncommon to find in either of those even in the US. But like Patrick said, its not very common in general use fixtures.

Is that ballast in a plant or aquarium fixture by chance?
F18T8 is not uncommon to find in either of those even in the US. But like Patrick said, its not very common in general use fixtures.

Its just a normal undercabainet work-light, have it in my gallery somewhere. Will photo the ballast tomorrow.

In Europe, F18T8 tubes serve as a direct replacement for F20T12 tubes in preheat fixtures only while F17T8 was designed for dedicated magnetic rapid start ballasts or electronic instant start ballasts.

Indeed. F18T8 are intended as a direct retrofit for F20T12 in their preheat ballasts, and won't start on rapid-start or trigger-start ballasts since they have krypton, while F17T8 have argon, and so would start on rapid-start or trigger-start ballasts. Each lamp requires its own ballast.