I have an APEC Water RO system that has recently stopped working properly (low flow caused by inadequate water in the tank). The system is ~14 months old, and I just recently changed the stage 1-3 filters. It appears that water is getting stuck in the stage 4 membrane and not making it to the tank and/or faucet. Here's what I've done to troubleshoot:
- Removed stage 1-3 filters and reinstalled them
- Drained tank and checked pressure while empty (7psi)
- Removed each quick connect fitting starting from the water line throughout the system, checking to see if water was flowing. Identified the exit line of the stage 4 membrane as where the water flow stopped
- Opened the stage 4 membrane (first time I've done so) to look for obvious issues -- but I have no idea what to look for and nothing seemed wrong
Any ideas on what might be causing this?