Condensate pipe

The condensate pipe is a pipe that essentially transports ‘condensate’ wastewater from your boiler to the drains outside of your residence.

All modern gas boilers now recycle the latent heat from the boiler’s waste exhaust gases. It results in condensing of water molecules within the waste gases to extract the heat. This is distinct from old non-condensing boilers that only extracted heat from the burning of gases.

Since modern boilers are able to extract the heat from waste gases, it makes them much more efficient.  But it also results in the formation of condensate (water vapor) as a consequence of this condensing process.

The condensate pipe is used to drain the extra water that your boiler makes when it cools down. As a byproduct of the condensed waste gases, the water, which is also called condensate, is slightly acidic and needs to be drained through a PVC or ABS pipe. Every metal pipe would rust.

So, the question “Where is the condensate pipe on my boiler?” is easy to answer. – It is the only pipe that is not made of metal that comes out of it.

Debris might accumulate in the condensate trap over time. Corroded particles from the heat exchanger could make their way into the sump and then the condensate trap. This causes the condensate to reverse its direction and return to the heat exchanger’s bottom. And this is how a condensate trap becomes clogged up!