The facilities glossary
The jargon of equipment manuals, repair quotes, and service contracts — defined in plain English, with links to the guides where each term earns its keep.
- Aerator
- The small screen assembly at a faucet's tip that mixes air into the stream. When one faucet runs weak, mineral scale in the aerator is the usual culprit — unscrew and soak in vinegar. Related guide →
- Ballast
- The device in a fluorescent fixture that regulates power to the tubes. Older magnetic ballasts hum by nature; a failing one causes flicker and slow starts. LED 'Type B' retrofits remove it entirely. Related guide →
- Backcheck
- The valve on a hydraulic door closer that cushions a door flung open hard — it slows the door, it is not a doorstop. Related guide →
- CAM charges
- Common Area Maintenance — the building operating costs a commercial lease passes through to tenants. Benchmark yours against our maintenance budget tool before assuming they're fair. Related guide →
- CEC (HDMI-CEC)
- Consumer Electronics Control — the HDMI feature letting devices command a TV (Samsung calls it Anynet+). Also the reason your meeting-room display switches inputs by itself. Related guide →
- CMMS
- Computerized Maintenance Management System — software for tracking work orders, assets, and preventive maintenance. Built for maintenance teams; most small offices run on email and memory instead.
- Control stop
- The shutoff valve beside a commercial flushometer, under a chrome cap. Turning its screw clockwise stops the water — the documented first step of every flushometer repair. Related guide →
- Diaphragm kit
- The standard rebuild part for a commercial flush valve, matched to the fixture's flush volume (GPF). A $15–55 part that fixes most running or weak-flushing commercial toilets. Related guide →
- Dogging
- Holding a panic bar's latch retracted (via hex key or key cylinder) so the door works push/pull during business hours. Prohibited as a mechanical feature on fire-rated doors. Related guide →
- Duty cycle
- How long a machine may run before it must rest — shredders (e.g., 20 minutes on, 30 off) and standing-desk motors (~10%: 2 minutes of motion per 18 of rest) both enforce theirs with thermal shutdowns. Related guide →
- Economizer
- The damper system on a rooftop HVAC unit that cools with free outside air when weather allows. Field studies find 60–80% of them silently broken — wasting $1,000–3,700 per unit per year. Related guide →
- Fail-safe / fail-secure
- What a lock does when power dies. Fail-safe unlocks (maglocks — life safety); fail-secure stays locked (most electric strikes). The distinction drives fire-code decisions on every access-controlled door. Related guide →
- Flapper
- The rubber seal at the bottom of a toilet tank. When it degrades, the toilet runs — replacing it ($12–30, tool-free) is the most common toilet repair in existence. Related guide →
- Flushometer
- The tankless commercial flush valve (Sloan Royal/Regal class) on office toilets and urinals — flushes from line pressure, rebuilt with diaphragm kits rather than replaced. Related guide →
- Fuser
- The unit in a laser printer or copier that melts toner onto paper at high heat. Fuser-class error codes (Canon E000s, Ricoh SC54x, HP 50.x) dominate copier failures, and repeated resets against a real fuser fault cause damage. Related guide →
- GFCI
- Ground-Fault Circuit Interrupter — the outlet with TEST/RESET buttons. One GFCI protects a string of downstream outlets, which is why half the kitchenette dies until you find and reset it. Related guide →
- GPF
- Gallons Per Flush. Printed on flush valves and fixtures; repair kits must match it — a low-GPF kit in a conventional fixture produces the mystery weak flush. Related guide →
- HDMI handshake
- The negotiation between a display and source (including HDCP copy protection). When it fails — 'No Signal' on a working setup — the documented cure is disconnecting both ends and cold-booting both devices. Related guide →
- High-limit switch
- The overheat safety in furnaces and water heaters. Limit trips usually mean restricted airflow (change the filter); on water heaters it's the hidden red reset button behind the panel. Related guide →
- IWMS
- Integrated Workplace Management System — enterprise software combining real estate, facilities, and space management. What large corporations run; what nobody at a 40-person office needs.
- Maglock
- An electromagnetic lock holding a door by magnetic force. Requires power to stay locked (inherently fail-safe); weak holding usually means a misaligned armature plate or dirty mating faces. Related guide →
- NFPA 101
- The Life Safety Code — source of the emergency-lighting test requirements (monthly 30-second, annual 90-minute) and the egress rules that make chaining an exit door illegal. Related guide →
- P-trap
- The U-bend under every drain holding a plug of water that blocks sewer gas. In unused floor drains the water evaporates within weeks — and the office starts smelling like a sewer. Related guide →
- PIR sensor
- Passive infrared occupancy sensor — sees heat in motion, needs line of sight, and can't detect someone sitting still. Why the lights go off on people typing, and why dual-technology sensors exist. Related guide →
- Preload
- Door pressure binding a latch against an electric strike so it buzzes but won't release. Diagnosed by relieving pressure while badging; cured by fixing the pressure source or a preload-rated strike. Related guide →
- PTAC
- Packaged Terminal Air Conditioner — the through-wall unit under hotel and some office windows. A cousin of the mini-split with its own filter and drain maintenance needs.
- RBC
- APC's Replacement Battery Cartridge system — the user-swappable battery packs in office UPS units, replaced every 3–5 years (sooner in hot closets). Related guide →
- RTU
- Rooftop Unit — the packaged heating/cooling machine over most offices, strip malls, and clinics. Serviced from the roof; famous for broken economizers, worn belts, and clogged drains. Related guide →
- Sweep and latch speed
- The two main door-closer adjustments: sweep governs the main closing arc, latch the final few degrees that seat the latch. Clockwise = slower, an eighth of a turn at a time. Related guide →
- Watchguard
- Lennox's soft-lockout state after failed ignition attempts — the furnace waits (up to 60 minutes) and retries automatically. Usually announcing a dirty flame sensor. Related guide →