Equipment & Installation
20% of this examPumps, filters, heaters, chemical feeders, and the electrical protections around them. Questions are practical: how each filter type gets cleaned, what the multiport valve positions do, why the gauge reading matters, and the installation details — bypasses, check valves, bonding, GFCI — that keep equipment and people safe.
Core concepts
Know each filter's cleaning ritual
Sand: backwash, then rinse briefly to resettle the bed and flush dirty water to waste. DE: backwash, then recharge with fresh DE through the skimmer to precoat the grids — the powder is the actual filter medium. Cartridge: no backwash; remove and clean the element. Service trigger for all: pressure commonly 8–10 psi above the clean baseline.
The multiport valve is six answers waiting
Filter (normal), backwash (reverse flow to waste), rinse (resettle and flush after backwash), waste (bypass filter to drain — heavy vacuuming, lowering water), recirculate (circulate without filtering), closed (never run the pump on it).
Heaters: speed vs efficiency, and protect the exchanger
Gas heats fast regardless of air temperature; a heat pump moves heat from the air, delivering several units of heat per unit of electricity (COP > 1) but slowing as air cools. Pipe a bypass to keep exchanger flow in range, and put a check valve between the heater and a downstream tablet feeder so concentrated chlorine can't backflow and corrode it.
Electrical and automation basics
Bonding ties metal parts to the same potential (shock-gradient protection); GFCI opens the circuit on small leakage currents (people protection) — they are different answers to different questions. Salt generators make chlorine from dissolved salt by electrolysis; freeze protection starts the pump near freezing because moving water resists freezing.
Key facts to know cold
See it drawn out
- Clean starting pressure12 psi
Record it at startup — it's the baseline.
- Service trigger zone21 psi
Backwash or clean at roughly 8–10 psi over the clean baseline.
Where it lives in your books
The real exam is open book. Knowing which book — and which tab — answers this domain is worth as much as memorizing it.
Lookup strategy
- · Equipment questions usually hinge on one word — backwash, rinse, recirculate, precoat, bypass. Match the word to the component's manual function before reading the choices.
- · Electrical questions: ask whether the hazard is touch voltage between surfaces (bonding) or current through a person to ground (GFCI).
Reading isn't learning — retrieval is.
32 questions in this domain, each with an explanation and source.