DN20 Insulation Jacket

This Greenlife DN20 insulation jacket fits over a DN20 (3/4in) closed circuit filter housing to reduce heat loss and stop condensation forming on the casing where it sits inline on a heating pipe run. WrekinWater supplies it as a direct replacement for a damaged, missing or perished jacket rather than a generic pipe lagging wrap. Fitting it keeps a warm-side filter from radiating heat into a plant room and from sweating in a cold one.

Signs you need this part

• The original jacket is torn, compressed or missing from the housing.
• Condensation or drips forming on the bare housing casing in a cold plant room.
• The pipework around the filter feels noticeably hot to the touch, suggesting heat loss.
• You've replaced the DN20 housing itself and it's arrived without its insulation cover.

A closed circuit filter sits directly in the heating flow, so an uninsulated DN20 housing loses heat into the surrounding room and, on a cold pipe run, can attract condensation that drips onto nearby electrics or flooring. The jacket is shaped specifically to the DN20 housing rather than being generic pipe lagging, so it seals around the awkward union and valve fittings that a wrap-around lagging can't cover properly. Leaving a housing bare doesn't stop the filter working, but it does waste heat and risks damp damage around the plant room over time.

WrekinWater, a family-run water treatment specialist based in Bettisfield, Shropshire with 15 years and more than 50,000 customers behind it, stocks the genuine Greenlife jacket sized to fit the DN20 housing correctly rather than a universal lagging that won't seal around the fittings.

How to fit it

1. Isolate the heating system if you need to remove any existing damaged jacket first.
2. Wipe down the housing casing so the new jacket beds against a clean, dry surface.
3. Wrap the jacket around the DN20 housing body, aligning the cut-outs with the union and valve fittings.
4. Secure the jacket using its fitted straps or fastenings so it sits snugly with no gaps.
5. Check the union and any test points are still accessible for future servicing.
6. Restore the system to normal use and check for any condensation once it's back up to temperature.