No it's not sealed airtight. Support replied with the following.
First I would like to apologize for the inconvenience that was caused to you.
Replying to your question, no it is not supposed to be like that and this is not normal behavior of the device.
Let me explain the main cause of this unfortunate issue:
- One of the valves ( valves 1 or 2) has failed, leading to an overflowing relief valve ( the upper valve), this valve is not supposed to leak water.
- The saltwater leaking from the relief valve rusted out the Ro draining pump.
So replacing the pump alone without fixing the main cause of the problem will only postpone the issue until the new pump starts rusting again.
To ensure this issue will not happen again, we will send you as soon as possible, a brand new pump, and brand new valves along with tutorial videos on how to replace them.
The valves in question here are the one directly connected to the Tank water input and the one directly above it.