QTZ15 - Daro ECO-1 Quartz Sleeve for 15w Systems

The QTZ15 is the replacement quartz sleeve for Daro ECO-1 UV systems fitted with a 15W lamp, supplied by WrekinWater under stock code 15WQS. It fits directly over the lamp in the ECO-1 unit, keeping it dry while letting UV-C light through to disinfect the water passing by. This is an entry-level domestic UV system, so the sleeve is sized specifically to the 15W lamp used in it.

Signs your quartz sleeve needs replacing

• The sleeve has turned cloudy or discoloured instead of staying clear.
• You can see scale or a filmy coating on the outside of the glass.
• Water starts to taste or smell slightly off even though the ECO-1 lamp is lit.
• The sleeve has been in place for around 12 months, the standard replacement interval.

On a small domestic unit like the ECO-1, the 15W lamp relies entirely on the quartz sleeve to deliver its UV-C dose into the water, since the sleeve is the only thing between the lamp and the flow. Even light scaling or a slight haze on the quartz can meaningfully reduce transmittance on a lower-wattage lamp like this one, cutting the effective UV dose the water receives. Because the lamp still lights up normally, a fouled sleeve is easy to miss until water quality or taste starts to suffer.

WrekinWater is a family-run water treatment specialist in Bettisfield, Shropshire that has helped more than 50,000 customers over 15 years, and keeps genuine Daro parts including the QTZ15 in stock. Getting the correct sleeve for your ECO-1's 15W lamp avoids fitting an oversized or undersized generic sleeve, from a supplier rated Excellent on Trustpilot.

How to replace it

1. Turn off the water supply to the ECO-1 unit and disconnect the power.
2. Undo the retaining nut at the end of the housing and slide out the 15W lamp first.
3. Withdraw the old QTZ15 sleeve and wipe out the housing.
4. Fit a new O-ring before inserting the replacement sleeve into the housing.
5. Carefully refit the lamp and reassemble the retaining nut.
6. Restore water and power, check for leaks, and run to drain briefly before drinking the water.