Installation, Maintenance & Troubleshooting Flashcards
7 cards from real CWS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Installation, Maintenance & Troubleshooting flashcards as text
When installing a whole-house filter system on a well water supply, where should the pressure tank be positioned relative to the filter?
Answer: Before all filters so filters see system pressure, not pump pressure surges
The pressure tank should be installed between the pump and the filters so it absorbs pump pressure surges and the filters receive steady, regulated flow.
A water softener's resin bed is compacted and causing very low flow rate. Which maintenance procedure directly addresses this problem?
Answer: Performing a high-rate backwash to re-classify and loosen the resin
High-rate backwashing lifts and re-classifies compacted resin beads, restoring void space and normal service flow rates.
Which tool is essential for verifying proper installation torque on filter housing sumps to prevent leaks without cracking the housing?
Answer: Strap wrench
A strap wrench applies even gripping pressure around the housing without marring or cracking it, unlike metal-jaw tools that can damage plastic sumps.
After replacing the membrane in an RO system, the technician records a TDS rejection rate of 72%. What does this indicate?
Answer: The membrane may be incorrectly installed or damaged
A properly functioning RO membrane should reject 95–99% of TDS; a 72% rejection rate indicates the membrane may be installed backwards, pinched, or defective.
A chlorine injection system is overshooting the target residual after the contact tank. Which adjustment should be made first?
Answer: Reduce the chemical pump stroke length or rate
Reducing the chemical pump's stroke length or frequency decreases the chlorine dose, bringing the residual down to the target range.
What is the function of the distributor tube in a mineral (resin) tank?
Answer: To evenly distribute influent water over the top of the resin and collect treated water from the bottom
The distributor tube (with upper basket/screen and lower screen) ensures even flow distribution into and out of the resin bed for both service and regeneration cycles.
A homeowner reports that their water softener uses salt but the hardness at the tap is unchanged. After confirming the resin is functional, what should the technician check next?
Answer: Whether the bypass valve is partially open
A partially open bypass valve allows hard water to mix with softened water, delivering blended hard water to the household despite normal softener operation.