UV Lamp & Sleeve Replacement
Lamp replaced on interval, quartz sleeve cleaned, controller and alarm verified. The disinfection stage is the one component that fails without any warning at the tap.
The short answer
A UV lamp on a rainwater system should be replaced about every 420 days. Lamps keep glowing long after their output falls below an effective disinfection dose, so a lamp that looks fine can be doing nothing. The quartz sleeve also needs cleaning annually, because scale on the sleeve blocks UV even with a new lamp installed.
This is the component most often found failed on systems we inherit, and the failure is silent. There is no taste, no smell, and no pressure change when a UV lamp stops disinfecting. The install date is the only reliable indicator.
Before you call
Three things worth checking before you book. The first one answers it most of the time.
If there's no date written anywhere and you don't remember changing it, assume it's due. This is the one component where age matters more than appearance.
Most units display a specific fault. Write down what it says before you call — it tells us whether we're bringing a lamp, a sleeve, or a controller.
Look for the glow through the sight port. No glow points at power or ballast; a glow with an active alarm points at output decay.
How we diagnose it
UV problems are rarely visible in the water. What the controller is doing tells you more than what the tap is doing.
| What you're seeing | Usual cause | What it takes to fix |
|---|---|---|
| Controller alarm sounding | Lamp past service life | Lamp replacement and controller reset. |
| Lamp glowing but alarm on | Output below effective dose | Replace the lamp. Glow is not dose. |
| No light at all, no alarm | Power, ballast, or controller fault | Diagnose supply and controller before replacing the lamp. |
| Bacteriological test failed, lamp new | Scaled or clouded quartz sleeve | Clean or replace the sleeve. Scale blocks UV through a new lamp. |
| Water smells like rotten eggs | Carbon exhausted, not a UV fault | Carbon replacement, then verify UV separately. |
| Alarm returns within months | Upstream sediment shadowing the lamp | Correct the filtration stage ahead of the UV unit. |
The visit
Stored codes and elapsed hours tell us what the unit has been doing since the last service, not just what it's doing right now.
Correct lamp for the model, installed without touching the glass, and the hour counter reset so the next interval is accurate.
Scale on the sleeve blocks UV even through a brand new lamp. The sleeve gets cleaned every visit and replaced when it's clouded past recovery.
Sediment reaching the chamber shadows the lamp, so we look at the filtration ahead of it before signing the unit off.
Equipment
We service every common UV platform and stock lamps for the units we see most. Tell us the model number when you book and we'll bring the right lamp.
Related
FAQ
About every 420 days. Lamps keep glowing well after their output has dropped below an effective dose, so a lamp that looks fine can be doing nothing at all. The install date is the only reliable indicator.
Yes. We run bacteriological and general chemistry testing and give you the written results. If something comes back out of range, we will tell you which stage of the system is responsible and what it takes to fix it.
Usually yes, at least for part of it. Filter housings and UV units are almost always mounted inside a utility room or garage, so we need interior access. Tank, gutter, and first-flush work can be done without you there.
Yes. We service rainwater systems regardless of age, brand, or who built them — concrete cisterns, poly tanks, twenty-year-old fiberglass, all of it. If the original installer is out of business or unresponsive, that is the most common reason people call us.
