UV water system alarm, beeping or lamp out

Most UV alarms are the lamp-life countdown reaching zero or a timer that was not reset after a lamp change. A true lamp-failure alarm, a ballast fault or a low-UV reading on a monitored unit means water may not be disinfected: treat the water as unsafe until the cause is fixed and the plumbing is shocked. Exact alarm patterns and reset steps differ by controller, so confirm on the unit's label or manual.

Single source ~60 min moderateBrands: VIQUA, Sterilight, Pelican, Most residential UV brands

Before you start

Never look at a lit UV lamp or power it outside the chamber: UV-C burns eyes and skin
Unplug and wait about 10 minutes for the lamp to cool before handling; depressurize before removing the sleeve
Lamps contain mercury: handle carefully and dispose of as hazardous/universal waste
Until the system is fixed and the plumbing shocked, advise the customer to boil drinking water or use bottled water (well systems especially)

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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