RO/DI water screw up
 

I started to make some water last night and turned on the hot water instead of the cold...Oops....the machine ran hot water for close to an hour. Would there be any damage to the filter cartridges

Very likely your RO membrane is shot.

Your best way to test this is to measure the TDS of the water at these points:

- before everything
- before the RO
- after the RO
- after the RO (waste water)
- after the DI


Ideally the water after the RO should be close to zero. We have similar water (I'm in Edmonton), and my pre-RO TDS ranges from 170 - 210, and my post-RO/pre-DI TDS ranges from 0 - 2. If you have higher pre-DI TDS, then your DI media will be used up very quickly.