Condensate Trap
Also known as: condensate siphon, condensate U-bend, boiler trap
A water trap (U-bend) on a condensing boiler's condensate outlet that prevents combustion flue gases from escaping back through the condensate drain pipe.
At the base of the boiler condensate outlet pipe, before the drain connection.
Small white plastic U-bend, 21.5 mm or 32 mm diameter. Sits in the condensate pipework below the boiler.
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Always turn off the water supply before replacing any part. If in doubt, consult a qualified plumber. Gas components must only be worked on by a Gas Safe registered engineer. Unvented (pressurised) hot water systems must be worked on by a G3-qualified engineer. Prices shown are indicative — check retailers for current pricing.