Condensate Disposal from Condensing Boilers
Every condensing boiler produces mildly acidic condensate that has to reach a drain.
Every condensing boiler produces mildly acidic condensate that has to reach a drain. How that short pipe is run decides whether your boiler keeps working through a cold snap or locks out on the first frosty morning.
Internal beats external
An internal termination to a soil stack or internal waste is the preferred route because it cannot freeze. External runs are a fallback, not a first choice.
If it must go outside
Larger bore, insulated, as short as possible, with continuous fall and terminating below the water line of a gully rather than dripping onto it.
Pumps where gravity fails
A condensate pump handles basements and awkward positions, and needs its own power supply and a safety interlock where available.
Stop repeat winter lockouts
If your boiler has frozen more than once, we can look at rerouting or upsizing the condensate rather than just thawing it again.
Questions we get asked
Why does my boiler fail every cold morning?
A frozen condensate is the classic cause and is covered on our dedicated fault page.
Can it discharge onto the garden?
It is acidic and should reach a proper drain, soakaway or gully arrangement rather than being left to run onto the ground.
Can the pipe be rerouted internally?
Often yes, and if your boiler freezes annually that is usually the permanent fix worth paying for.