Modern condensing boilers produce acidic condensate that must discharge to a suitable drain using an appropriate route and materials. An internal route is often preferable where practical because it reduces the length exposed to freezing weather.
Where part of the pipe has to run outside, correct sizing, fall, insulation and termination become important. Poorly designed external condensate runs can freeze during cold Glasgow weather and cause the boiler to lock out.
The route should be planned at survey stage, especially if the boiler is being moved to a new location. Doherty's Glasgow boiler packages treat non-standard condensate work separately, so the survey can identify whether the proposed position needs additional drainage alterations.
