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028111 SITA UV 403 Replacement Quartz Sleeve QJ23370DE (Domed End)

028111 SITA UV 403 Replacement Quartz Sleeve QJ23370DE (Domed End)

QJ23370DE-028111

In stock

£43.00 inc. VAT
£35.83 ex. VAT
£43.00 inc. VAT
£35.83 ex. VAT
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Product Description

This is a compatible replacement quartz sleeve for SITA UV 403 disinfection systems, supplied by WrekinWater as part number QJ23370DE against SITA reference 028111. The domed end seats directly against the housing's end cap, protecting the UV lamp from direct water contact while letting UV-C light pass through to disinfect the water. It's a straightforward like-for-like swap for a sleeve that has clouded, scratched or reached the end of its service life.

Compatible System SITA UV 403
End Type Domed end
WrekinWater Part No. QJ23370DE
SITA Reference No. 028111
Material High-purity fused quartz glass
Recommended Replacement Every 12 months
Pack Quantity 1 sleeve

Signs your quartz sleeve needs replacing

  • Visible cloudiness, limescale or scratching on the sleeve surface
  • Water developing a yellow or brown tinge even though the lamp is lit
  • Your SITA UV 403's monitor or low-UV alarm triggering
  • The sleeve has been fitted for 12 months or more

The quartz sleeve sits between the UV lamp and the water flowing through your SITA UV 403, shielding the lamp from direct contact with the water while still letting UV-C light pass through to disinfect it. Over months of use, mineral scale, iron staining and fine scratching gradually reduce how much UV light actually reaches the water, so disinfection becomes unreliable even though the lamp is still glowing. Replacing the sleeve restores full UV transmittance and keeps the system working as intended.

WrekinWater is a family run business based in Bettisfield, Shropshire that has supplied water treatment parts to more than 50,000 customers over 15 years, and is rated Excellent on Trustpilot. This QJ23370DE sleeve is sized and shaped specifically for the SITA UV 403, so you get a straightforward like-for-like fit without guesswork.

How to replace it

  1. Isolate the water supply to the UV unit and drain the housing down
  2. Undo the retaining nut or union at the base of the housing
  3. Withdraw the UV lamp first, then carefully slide out the old quartz sleeve
  4. Clean the inside of the housing and fit fresh O-rings
  5. Insert the new QJ23370DE sleeve and refit the lamp
  6. Restore the water supply and power, then run the system to drain briefly before use

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028111 SITA UV 403 Replacement Quartz Sleeve QJ23370DE (Domed End)

028111 SITA UV 403 Replacement Quartz Sleeve QJ23370DE (Domed End)

£43.00 inc. VAT
£35.83 ex. VAT
£43.00 inc. VAT
£35.83 ex. VAT

Frequently asked questions

For full details on returns, refunds, eligibility, and timeframes, please refer to our complete Refund Policy here:

👉 Refund and Returns Policy

If you are unsure whether your item qualifies for return, please contact our team before sending anything back and we’ll be happy to help.

Yes, this domed-end sleeve is made to the dimensions of the SITA UV 403 housing, matching SITA reference 028111.

This is a compatible replacement sleeve manufactured to fit the SITA UV 403 rather than an original SITA-branded part, so it installs and performs as a direct swap.