CT-SWORDFISH Air Purification UV 36W Replacement Bulb 45% Off - $25.99! HOT PRICE!!!

[Neil]

The light looses it effectivness after approx 1 year. It still lights up (doesn't burn out) after that time so seeing light after the 1 year period doesn't mean that you don't need to change the bulb.

That's exactly right, the bulb can give off visible light for a long time, even after the UV has worn off. That's why I was hoping there was a way to easily test. Maybe hang a test strip in there for 15 minutes and see how much the color changes, that sort of thing.

[Mr Nobody]

We moved into our current home 3 years ago, and it had one of these Swordfish units installed. About 3 months after we moved in the red light came on indicating it was time to replace the lamp.

I haven't been able to find one on a shelf anywhere until I saw it at CT 2 months ago and missed that sale by 2 days ($36.99 incidentally). The lamp has emitted it's UV light the whole time. Whether or not it has been effective during that period is up for debate. I bought two of them (thanks OP) and the new lamp seems to be the same intensity.....

I'm not sure if I've helped or clouded the issue even more....

You can't see UV. Its emitting visible light, but probably no UV.

[Neil]

They recommend N95 masks (95% efficiency of 0.3 micron particles; contrast 99.9+% for HEPA) during the SARS outbreak, so unless your furnace filter is of particularly high quality, it won't trap pathogens dead or alive.

I did some reading out of curiosity.
It is generally a bad idea to check these lamps while it is powered on, because the UVC radiation is damaging to your eyes and exposed flesh (it damages DNA (bacteria, virus, people)).
You really need eye protection, and reduce skin exposure (wikipedia says UVC is more dangerous than UVA or UVB (atmospheric oxygen absorbs it so you don't normally worry about it)).

These lamps are similar to normal fluorescent lamps, except they use quartz glass and have no phosphorous coatings.

I am guessing like ordinary fluorescent lamps, these lamps should either be full on, or completely dead with no real diminished output state.

Somebody said this emits visible light during operation, I think that should be an indication that the lamp is operating properly(mercury is what gives off the UVC, but other filler gas ("argon, xenon, neon, or krypton") probably emit visible light).
You may want to just follow the replace warning light. Unless there is a timer, it is probably turned on by some measured electrical changes.

Since UVC is capable of damaging plastics and rubber, these should be mounted away from gaskets and seals.

That's very interesting stuff you have there. I'd been assuming that there was no correlation between the visible light output and the UVC output. But maybe they are linked? So if the bulb is still putting out sufficient light that you can see it glowing through holes & gaps in the duct, maybe it's still OK.

Personally I have zero faith that the manufacturer's built in nag sensor does anything more than act as a timed reminder to buy more bulbs. Looking at their massive markup suggests that could be the case. Trusting manufacturer dummy lights can waste a lot of money. Imagine if you changed your oil today but forgot to hit the reset, then next week you get a light that tells you to change it again.

[mrblond3]

You can't see UV. Its emitting visible light, but probably no UV.

Yep....you're right.

[jm1]

I jumped on this deal as well having in mind cleaning the air from viruses. Now I started to be concerned on the Ozone concentrations this lamp generates. The web site is just saying //Lamps are ozone free// without providing any evidence.
See for example the article:
http://www.newton.dep.anl.gov/askasc.../chem03323.htm

I will inquire the manufacture and update the thread here.

Yes, I was wondering that as well. The Swordfish site says the Philips bulbs they use don't emit ozone, and I've plugged it in yesterday and it's been on about 24 hrs and I don't smell any ozone at all. I also have an electronic air filter that does emit some ozone when freshly cleaned, so I'm well aware of what ozone smells like (unless ozone comes in a non-scented version).

You might have better luck googling the bulb model # and/or contacting Philips rather than Swordfish, but my unscientific nose test proves to me that the ozone from this bulb must be very, very low or none at all.

Installation tips: maybe my sheet metal is thicker than normal, but I had to drill pilot holes for the screws as they wouldn't go in easily by themselves and it look a lot of elbow grease to drill the 2" hole and I ended up using tin snips to finish it off after it drilled about half of the hole. Using tin snips to cut out a rough hole would've been much faster for me, although not as neat.

[bogey]

http://www.newton.dep.anl.gov/askasc.../chem03323.htm

If UV can generate ozone, the article really did not give an estimate of the rate of generation.
DC motors/fans, and appliances containing them generate ozone, and these things are far more prevalent.

I just noticed the wikipedia entry on fluorescent light mentioned the mercury in the lamp can be absorbed by the glass, presumably this eventually will deplete the mercury available to emit UVC ("and finally causes the lamp to glow a dim pink when the mercury runs out and the argon base gas takes over as the primary discharge.[citation needed]").
So the "glow test" is no good.

In the absence of some kind of UV-meter or test strip, it's difficult to make a replacement determination.
Many materials will glow when exposed to UV (wristwatch markings, features on Canadian paper money, ...), but most seem to be "overly" sensitive to any exposure, and would only be useful in determining a total lack of UV emissions.

The replace lamp soon light, be it timed or otherwise, might ultimately be of some value.
Even the change oil light in automobiles typically have some rational basis (runs off the odometer, ...).

Avoid gazing at the lamp "glow". When fully functional, UVC radiation accompanies the visible light, and is damaging to your eyes.

[Neil]

The replace lamp soon light, be it timed or otherwise, might ultimately be of some value.
Even the change oil light in automobiles typically have some rational basis (runs off the odometer, ...)

I don't see it the same way. Soda and potato chips now come with expiry dates of a few weeks even though the true shelf life is probably 10x longer. And if Swordfish can sell a $10 bulb for $50, why wouldn't they encourage you to change it far more often than you actually need to?

[venice_it]

I don't see it the same way. Soda and potato chips now come with expiry dates of a few weeks even though the true shelf life is probably 10x longer. And if Swordfish can sell a $10 bulb for $50, why wouldn't they encourage you to change it far more often than you actually need to?

I've had this lamp for about 3 years and I only used one swordfish bulb and bought some knockoff replacements. I found the original bulb went 13 or 14 months before the light started blinking to indicate to replace the bulb. I figured as well that the manufacturer's indicator would flash prematurely, but that was not the case with my bulb.

The knockoffs I bought would not reset the indicator light and it always flashed to change the bulb. I'm not sure how the indicator light works, if it is a sensor or timer or whatever, but it seemed to not reset or know that i was not using their bulbs.

I don't think you get zero UV light after a year, but I do think it is hugely reduced. I generally install new bulbs in late fall since that's when flu season might start. I think the science behind the system seems convincing, but it is one of those things that is difficult to pinpoint whether it is working for you or not since you can't tell if it prevented you from getting an illness you might not have gotten otherwise.

I don't think you can go wrong for this sale price for either the bulbs or the main unit. I paid about $160 for the unit and got generic bulbs for the price of the genuine ones on sale.

[bogey]

I don't see it the same way. Soda and potato chips now come with expiry dates of a few weeks even though the true shelf life is probably 10x longer. And if Swordfish can sell a $10 bulb for $50, why wouldn't they encourage you to change it far more often than you actually need to?

Possible but who knows.

Googled "uv detectors" and the first page returned components such as:


http://www.advancedphotonix.com/ap_p...p?from=leftnav

http://www.svta.com/products/uv/uv.htm

http://www.eoc-inc.com/UV_detectors_...hotodiodes.htm


It looks like solid-state UV detection is pretty routine and not expensive (these detectors are even unaffected by visible light).
I guess there isn't a big enough demand for consumer level products.


Since the UV lamp is basically identical to the normal fluorescent lamp in construction, I still think just like the normal fluorescent lamp/CFL in your house, the UV lamps are either fully on, or they are fully dead (the mercury depletion "theory" notwithstanding, when was the last time you noticed your CFL is down to half brightness and it's time to screw in a new one? I think the mercury depletion process is too long termed, and something else invariably goes wrong long before).
If anything, the normal lamp seem to always fail due to the loss of the emissive coating on the electrodes (the telltale dark deposits near the contacts of the lamp).

Edit: if full on/off => the "glow test" might still be valid (if the mercury simply do not deplete that quickly).

[leafs]

I have installed the unit in my cold air return. I have sealed all holes but I am getting a little of indirect blue light coming out around my filter as it is not a tight seal. Also on my main floor I have a cold air return and I am seeing a little bit of indirect light. Is this dangerous and should I move the UV light to above my furnacve and AC coil. Any feedback would be appreciated.

[bogey]

I have installed the unit in my cold air return. I have sealed all holes but I am getting a little of indirect blue light coming out around my filter as it is not a tight seal. Also on my main floor I have a cold air return and I am seeing a little bit of indirect light. Is this dangerous and should I move the UV light to above my furnacve and AC coil. Any feedback would be appreciated.

I would guess it is preferable to reduce these leakage as much as possible.

I would imagine the leakage around the filter is fairly minimal (if not, you might want to fix the leaky filter for starters), and unless it is in a high traffic area, should not be a serious problem.
The cold air return may be trickier.

You can use aluminum tape (note these are NOT fabric "duct tape") strategically where appropriate (any exposed adhesive may be degraded by the UVC, but the aluminum base will be unaffected).
Normal (borosilicate) glass actually absorbs UVC, that's why these lamps are made from fused quartz glass.
So strategically placed glass panel will be helpful.

[bogey]

Here are $0.02 more:

Unless the Swordfish lamp itself is sitting in view from your cold air return vent, chances are it had to bounce around a few times to leak out the vent. This probably diminished the intensity of the UV considerably.

Anything material that would block visible light will generally block UV.
But sufficiently intense UVC will damage many materials over time (textile, plastics, rubber, ...).

As mentioned previously, normal glass panel will block UVC (but not visible light oddly enough).
The problem is glass is difficult to work with. It also might reflect some of the UVC. It's like trying to build a darkroom with mirrors (a tricky job).

For example, it is easier to use some textile based furnishings (cotton, polyester, ...) to block a direct view to the vent.
Pick darker colors, since darker colors absorb more visible light, there is a good chance it also absorbs more UV.
If the textile becomes discolored over time, or show fraying, etc., then consider it a replaceable UV block.
I think chances are, any leakage is probably diminished greatly by the time it reaches the vent, and your blocking furnishings will merely serve as extra insurance.

If the Swordfish lamp is obviously very close to the vent, then you need to either move the lamp, or construct more elaborate isolation/labyrinth passages.
At the same time, you don't really want to choke off the air return in your efforts.

Wood can be used. Metals can be used, but metals will reflect UV (darkroom build with mirrors analogy again).

Oddly enough, transparent plastics Plexiglas & Lexan are UV blockers (used in some sunglasses). They might reflect UV also however.


Moving the Swordfish to the outbound ducts is an option.
I just don't know if there are UV-sensitive materials near the evaporator or the top of the furnace.


I came across this http://www.osti.gov/bridge/servlets/...ive/810964.pdf, where they tested similar UV lamps.
I just skimmed over it, but notably they reported NO ozone increase due to the application of these lamps.

[steinberg]

Between my furnace filter and humidifier, only have around 5' distance. It says need 3' away from filter or humidifier.
Above the a/C coil, I notice the air come out is very hot (as I touch the sheet metal outside). I have worry on leave the UV light on all the time at hot air like this.
Can anyone give me suggest where I should install it?

[maddawg]

Back on sale again. Purchased a honeywell truesteam humdifier. Anyone know if you can install this unit about the coil and the steam humdifier in the same general location. I have not been able to find a quick answer to this question.