DN50 & DN80 Service Kit

This Greenlife service kit provides the replacement seals for resealing closed circuit magnetic filter housings in either the DN50 (2in) or DN80 (3in) size, the two largest housings in the Greenlife range. WrekinWater supplies it for engineers and DIYers carrying out the annual clean-out on larger commercial or plant-room heating systems. It's listed as a single kit covering both sizes, so check which housing you're servicing before fitting.

Signs you need this part

• Weeping around the housing seam of a DN50 or DN80 filter once the system is back under pressure.
• Seals that feel hard, flattened or cracked when the housing was last opened.
• You're reassembling the housing after removing the magnet bar for its annual clean.
• Damp staining on the pipe lagging close to a larger plant-room filter housing.

On the larger DN50 and DN80 housings, the seals carry the full pressure of a commercial or larger domestic heating loop across a bigger sealing face than the smaller DN20-DN40 units, so any seal that's hardened or worn has more area over which to fail. Heat cycling and system inhibitors age the rubber long before the housing itself wears out, which is why a housing that resealed cleanly last year can weep once it's reopened and rebuilt. Fitting new seals at every service keeps a larger, harder-to-access housing from developing a slow leak that's awkward to trace later.

WrekinWater is a family-run business in Bettisfield, Shropshire that has supported more than 50,000 customers over 15 years and carries an Excellent Trustpilot rating. Stocking the correct DN50/DN80 kit here saves ordering the wrong size seals for a larger plant-room installation.

How to fit it

1. Isolate the heating system and let it cool fully before opening a larger housing.
2. Close the isolation valves either side of the DN50/DN80 filter to remove pressure from that section.
3. Release the union or clamp securing the housing body and withdraw it from the head.
4. Remove the old seals and clean the sealing faces, checking for scoring or debris.
5. Fit the new seals supplied in the kit and reassemble, tightening the union hand-tight plus a further quarter turn.
6. Restore pressure gradually by reopening the isolation valves and check the full circumference of the joint for leaks.