Replacement water filter cartridges and membrane for the Watts TGI 315 residential RO system.
We recommend that you change the carbon block water filter cartridges every 12 months and the membrane every 24 months.
1st stage: 5 micron carbon block (2.5 x 10'')
2nd stage: Watts W-1812-50 50gpd membrane. A thin film composite RO membrane for residential RO systems. (1.8'' x 11.8'')
3rd stage: 5 micron carbon block (2.5 x 10'')
* On some occasions a CTO 2510-05 cartridge (or similar) may be used in the kit. This does the same job as the Watts F109009. They're just different brands.
You can tell if the seals start leaking, which is obvious, I know.
Even if there are no leaks you may find that the profile of the O ring becomes flattened because of prolonged time under compression. The cross section should be round and if it's not it may not seal easily.
However, we recommend that you replace the O rings every two or three years as a precautionary measure.
One of the main reasons for changing O rings periodically is that as they age and compress, the housing bowl needs to be tightened excessively. That leads to difficulty loosening the bowl from the cap next time the cartridge needs to be replaced.
This is the basket Message
This is the basket Message