Why the urine canister has a hole in the lid – pressure equalization explained

If you've ever taken a closer look at your urine canister, you may have noticed this small hole in the lid.
And maybe you've asked yourself: Does that belong there – or is it a manufacturing defect?
Don't worry: the hole is not a mistake, but a deliberately integrated component with a clear function.

Coincidence or intention?

Of course intentional!
At ecoshit, every detail is carefully planned – from the screw to the seal.
The small hole in the canister lid is part of a sophisticated system that makes using your composting toilet more efficient and reliable.

The purpose of the hole – pressure equalization in the canister

The hole serves to equalize the pressure .
When urine flows into the canister, the displaced air must be able to escape.
Since the odor trap works airtight – to prevent odors – it needs a small opening to equalize the air pressure.
This is the only way the urine can flow evenly and without bubbling.

What happens without the hole?

Without this opening, the urine would:

• run much slower,
• back up in the separator insert,
• or in the worst case, overflow.

Especially when there are differences in altitude, for example in a camper or van, excess pressure builds up in the canister.
This prevents urine from draining and can unbalance the system – a typical problem with closed containers without ventilation.

Care tip

When cleaning your canister, make sure that the small hole is not clogged – for example, with limescale, dust or bedding.
Only a free air passage ensures that your system remains permanently clean, odorless and functional.

Conclusion: Small hole, big impact

The hole in the lid of your urine canister is a crucial part of the system.
It ensures even drainage, prevents backflow, and supports the odor-tight operation of your composting toilet – a small but essential detail for smooth operation.