PIN out on Aqua UV sterlizer

[Aquavaj]

I have a classic 40watt which I bought a new bulb for but it's not lighting up. The plug has 4 holes for the 4 pins on the bulb. Does anyone know the specs on the pins so I can try testing with a multimeter to see if the power supply is bad?

 

[Fredlee]

Reason they probably don't publish that information.

Multimeter Usage (Advanced):

• UV lamps require high voltage (often exceeding 500V) to strike the arc and ignite the gas, which can exceed the limits of a standard multimeter.
• A properly functioning electronic ballast should produce a surge voltage which some multimeters can detect (often around 350V, but this is a specific surge).
• An improperly functioning ballast will likely only show a normal, low operating voltage or no voltage at all.
• Caution: Measuring high voltage can be dangerous. It's often safer to simply replace the bulb first (as bulbs have a limited lifespan of around 14 months) to rule it out before concluding the power supply is faulty

 

[BeanAnimal]

@Fredlee That looks like an AI response.

Please don’t use AI to post.

But yes, an multimeter in this case is not a good idea unless one fully h def stands the output rating and meter specifications.

I have a classic 40watt which I bought a new bulb for but it's not lighting up. The plug has 4 holes for the 4 pins on the bulb. Does anyone know the specs on the pins so I can try testing with a multimeter to see if the power supply is bad?

Let’s backup.

Why was the lamp replaced to begin with?

Was the old lamp firing?

What is the source and exact model of the new lamp?

40W filament wiring is not universal, nor is pin length.

 

[Fredlee]

While I don't quite agree with @BeanAnimal about AI,perhaps this quote will further bolster my previous post. As well as instructions on how to test.

The most reliable and commonly recommended way to test the transformer is to connect a known working UV lamp of the exact same wattage and type (e.g., a new or confirmed good Aqua Ultraviolet bulb).

• Plug in the transformer and insert the good lamp.
• If the lamp lights up (you may see a faint blue glow at the ends—do not stare directly), the transformer is likely good.
• If it doesn't light, the transformer is probably faulty.

This is the method Aqua Ultraviolet reportedly advises, as multimeter voltage readings on the output can be unreliable or unpredictable for these ballasts (due to how they regulate current for gas discharge lamps). Many users and forums confirm this approach, noting that buying a replacement bulb first is cost-effective (since bulbs need annual replacement anyway).

1. Check Continuity/Resistance (Transformer Unplugged):
   • Test primary winding (input side): Should show low resistance (a few ohms to tens of ohms).
   • Test secondary winding (output to lamp): Higher resistance, but continuity (not open).
   • No continuity means it's open/broken.
2. Output Voltage (Advanced—Use Caution):
   • With no lamp connected, measure open-circuit voltage at the lamp sockets or output wires.
   • For these ballasts, it may show high voltage (hundreds of volts) briefly for starting.
   • However, readings can fluctuate or be misleading without a load (the lamp). Some sources note multimeters may not accurately predict if it will properly start/run the lamp.

If input is good but no output or erratic readings, the transformer is likely bad.

 

[Quietman]

Worked a lot with electronics in the Navy and still if it were me, I'd get a new bulb. You know how I know I would...my light stopped working a few weeks ago. I have a multi-meter but I really dislike working with cords and high voltage starters for lights. I ordered a light bulb. It worked just fine when I replaced it. If it hadn't I likely would've just ordered the transformer.

 

[BeanAnimal]

While I don't quite agree with @BeanAnimal about AI,perhaps this quote will further bolster my previous post. As well as instructions on how to test.

You don’t have to agree with me it is the wishes of the site owner and management and arguably the bulk of the active membership.

AI generates tangentially relevant noise, not conversation. It is often wrong, conflates information, hallucinates, misses general context, or blathers on instead of being succinct.

This is a site for human conversation. Anybody here can go search or use AI on their own.

 

[Fredlee]

You don’t have to agree with me it is the wishes of the site owner and management and arguably the bulk of the active membership.

AI generates tangentially relevant noise, not conversation. It is often wrong, conflates information, hallucinates, misses general context, or blathers on instead of being succinct.

This is a site for human conversation. Anybody here can go search or use AI on their own.

That's fine, I won't bother answering questions with AI quotes. But in case your not aware AI's very dramatically. While my first response did use Google AI my second quote used Grok which is entirely different. It scans the entire web and posts the available information and quotes from the actually manufacture. I also review the information for accuracy before my posts. But not a problem, I will respond with my own knowledge in the future. I have been involved with this hobby since the early 70's. Have a good day.

 

[BeanAnimal]

I will respond with my own knowledge in the future. I have been involved with this hobby since the early 70's. Have a good day.

Thanks, that's exactly what we are looking for.

We would love to hear about your knowledge and experience in your own words! That is what makes sites like this so valuable.