Can UV leak toxins?

[buruskeee]

I understand stray voltage can leak out if the seams start degrading in a UV unit, but are there any toxins that can leak out?

Let’s say the bulb stays intact. If the quartz cracks and water gets into the quartz and touches the bulb, but it doesn’t short, can toxins leak into the water? If so what?

 

[buruskeee]

@Randy Holmes-Farley do you know of any possible toxins/chemicals that can come from a UV bulb that is intact?

 

[ISpeakForTheSeas]

Let’s say the bulb stays intact. If the quartz cracks and water gets into the quartz and touches the bulb, but it doesn’t short, can toxins leak into the water? If so what?

I'm curious what Randy has to say, but:

To my knowledge you don't need to worry about chemicals at all, but you probably should be concerned about the casing degrading, as that can lead to leaks (and if it gets thin enough, it can also lead to you being exposed to any UV that makes it through the thinning plastic of the casing).

This thread has comments from a few different people with the same issue - they suggested fixing it using a heat gun to remove the casing and replace it with new, black PVC:

UV light penetrating casing

Hi All, I have a pentair smart uv 40w running about 600GPH flow for a 220 gallon plus reef tank. Ive owned the unit for about 3 years now and have changed the bulb and glass sleeve twice. It seems to work with out issue until month week when i walked into my garage and saw that it was...

www.reef2reef.com

 

[Doctorgori]

you sure the bulb is sealed and did you already check for stray volts?
not saying it’s likely…..just going down the checklist
edit 3x …dang spell check
Also has the UV ever been on without flow?

 

[DaJMasta]

If the bulb cracks and water gets in, there are toxic chemicals in the bulb, but the quartz sleeve breaking only exposes the water to the metals of the electrical contacts - not good in prolonged exposure, but provided they're not still in operation, similar to dropping something metal in your tank.

If the UV is still operational, there is basically no risk of the toxic chemicals in the bulb getting out, since the bulb must maintain a vacuum seal (preventing their escape) to operate. It is unlikely the UV will still operate with water ingress beyond the quartz sleeve (it will short it out.) The only other significant risk is electrical, but this is much more dependent on the robustness of the initial design and proper mounting/maintenance to keep the saltwater off of those electrical contacts, and that risk is the same to any AC operated submerged or at least in part submerged device.

 

[buruskeee]

you sure the bulb is sealed and did you already check for stray volts?
not saying it’s likely…..just going down the checklist
edit 3x …dang spell check
Also has the UV ever been on without flow?

I had the pump seize that was feeding an Aqua UV unit (both inlet and outlet points upward) for maybe 2 hours. I’d imagine the water staying in the unit made it a nonissue.

It’s in a spot with wiring that will be tough to take apart on my own, so I just haven’t turned it on. When I fixed the seizure of the pump, the UV bulb was still turning on (glow) and wattage from it seemed normal, so I don’t believe it’s damaged.

I’m just worried if there’s anything besides stray voltage that can leak out of a functioning unit.

If the UV is still operational, there is basically no risk of the toxic chemicals in the bulb getting out, since the bulb must maintain a vacuum seal (preventing their escape) to operate.

This is exactly what I wanted to get clarity on. Thank you.

 

[DaJMasta]

I'd add that any visible damage to the quartz sleeve should be reason enough to stop using it - salt ingress would only be a matter of time and it would then only take a moment to short out and potentially damage the bulb or the sleeve more thoroughly, but if the sleeve is good and sealed in place, everything in contact with the water is inert (plastics, o rings, quartz glass), so you should be fine.

 

[buruskeee]

I'd add that any visible damage to the quartz sleeve should be reason enough to stop using it - salt ingress would only be a matter of time and it would then only take a moment to short out and potentially damage the bulb or the sleeve more thoroughly, but if the sleeve is good and sealed in place, everything in contact with the water is inert (plastics, o rings, quartz glass), so you should be fine.

Sleeve is relatively new.. installed 3 months ago and cleaned 6 weeks ago. I will inspect it again when I have some down time in the next couple weeks.

 

[ca1ore]

I understand stray voltage can leak out if the seams start degrading in a UV unit, but are there any toxins that can leak out?

Let’s say the bulb stays intact. If the quartz cracks and water gets into the quartz and touches the bulb, but it doesn’t short, can toxins leak into the water? If so what?

Not sure what you mean by stray voltage leaking? If the quartz sleeve cracks or the O rings degrade to the point where the unit is no longer watertight the unit will short out and you will see water on the floor. In many decades of using UV sterilizers, I have never had a quartz sleeve break. I do replace the O rings about every 5 years.