Created by Pooja Pednekar 2025-07-17

The protocol is created to give detailed information about the tank systems, its maintenance, cleaning and troubleshooting. The tanks included in this protocol are DI Tank, Salt Mixing Tank, Header Tank, Two Blue Tanks as well as the display tank managed by the Putnam Lab.

1. DI TANK SYSTEM

#### A. Working of the DI Tank System The tank has a freshwater input from the wall behind the blue tanks 3 and 4. It opens into a valve which when turned on, lets the water go through the filteration system.

• The filteration system comprises of the four filters: Two of the DI Resin Filters (#1 and #2), Carbon Filter (#3) and Sediment Filters(#4).

• General tube system working: The blue tube connected to the main valve gets the water into the sediment filter. The sediment filter is connected to the carbon filter internally and pushes the water into it. The carbon filter is connected to the DI dual-stage RO (two-row reverse osmosis) which helps to get rid of any water impurities. The blue tubes coming out from the RO system continues to channel water finally into the resin filters. There is an additional, yellow-black tubes coming out of both the RO systems which is the discarded water from the system that drains out of the system. Once the water enters the resin filters, it gets deionized before entering the DI tank for storage via another black tube.

Make sure the black tube entering the DI Tank is plugged in whenever you try to fill up the DI tank.

• DI Usage Tracking: The tank has a write-on tape where you want to track and write the start time and date for when you started the DI system. Additionally, please also track the usage on the DI Usage Tracking List to access it anytime.

#### B. Filter System: Cleaning, Working and Tracking

• Filter Changes Tracking List: The Resin Filters are set to change whenever the resin turns dark brown or you no longer see the blue beads. This could be within 2-3 months after filling new resin. The Carbon Filter should be changed ~1 month while the sediment filter need to change every 100 gallons of water use/every time you start the DI system.

  Whenever you change any filters in the DI system make sure to track that on the tracking list and update the inventory accordingly.

• All the excess filters and resin beads are stored in a box or under the table, closer to the wall opposite blue tank 1 and 2.

• Cleaning of the filters:

  1. Resin Filters - Before cleaning: Make sure you were gloves as the microplastic beads could stick to your hands possibily leading to enter the tank system if you are under cleaning duties. You should also have a trash can to dump the resin beads off as well as a small container and cloth that you can throw off after cleaning.
     • During cleaning:
  2. Clean filters one by one (as there are two resin filters #1 and #2). Take out the filter housing with the help of the wrench placed near the system.
  3. Once you have successfully taken out the housing which has the filters inside, empty access water into the container near you and empty it in the drainage hole near the fridge.
  4. Once emptied, take out the resin filter container outside take off the cap to get rid of the inside resin.
  5. The filter inside would first have a sponge so carefully take the beads off the sponge and with the help of the kim wipe/cloth take it off carefully in the trash can.
  6. Empty all the used resin in the trash can till you can take most of it off and fill it up with the resin from the bag.
  7. Please make sure you fill up the beads till the fill line as you still need to house the sponge into the container. Once ensured, make sure you take any beads off on and between the cap for a successful seal.
  8. After the above steps are done, follow the arrow on the container and ensure that you follow the UP arrow before placing it in the filter housing and complete cleaning.
  9. Follow the same process for the #2 and make sure you clean both of them at the same time.
     • After cleaning: Make sure the housing properly fits into the holder by turning the valve on and unsure there are no leaks.

  10. Carbon Filter : The process is simple by taking the filter housing off with the wrench and just inserting a new carbon filter in the housing. This filter is changed almost every month.

  11. Sediment Filter : The sediment filter change is similar as cleaning the carbon filter.