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Common repairs

Plumbing

Commercial Toilet Keeps Running? How to Troubleshoot a Flushometer

If a commercial toilet will not stop running, close the control stop first. The most common causes are debris in the flushometer, a restricted diaphragm bypass, damaged internal parts, or the wrong repair kit.

HVAC

RTU Fan Runs but No Cold Air: What Maintenance Should Check

If the rooftop fan runs but supply air is not cooling, the airflow circuit is alive but the cooling stage may be locked out, not commanded, or unable to operate. Gather evidence before calling service.

Electrical & Lighting

GFCI Won’t Reset? Safe Checks Before Replacing the Receptacle

A GFCI that will not reset is not automatically bad. Unplug connected equipment, check for moisture, verify upstream protection, and try one firm reset. If it trips again or shows heat, odor, or damage, take it out of service and escalate.

Doors & Hardware

Commercial Door Closer Slamming? How to Adjust Sweep & Latch Speed

Most hydraulic commercial door closers have separate sweep and latch-speed adjustments. Make very small valve changes, test the full closing cycle after each change, and stop if the closer is leaking oil or the adjustment valve is near its limit.

HVAC

HVAC Condensate Drain Clogged? How to Clear a Routine Blockage

A clogged condensate drain can stop cooling, trip a float switch, overflow a pan, or stain a ceiling. If the drain and cleanout are safely accessible, remove buildup and verify that water flows freely before putting the unit back in service.

Plumbing

P-Trap Leaking Under a Commercial Sink: How to Find and Fix the Leak

A leaking sink trap is usually caused by a loose slip joint, crooked washer, cracked nut, damaged tubular piping, or a partial clog that makes joints seep. Dry everything first, then run water and identify the first point that gets wet.

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88 guides
PlumbingFlushometers, faucets, traps, drains, restroom repairs.HVACCooling, airflow, condensate, RTUs, heat pumps, VRF.Electrical & LightingConservative checks for receptacles, GFCIs, LEDs, sensors.Doors & HardwareClosers, latches, panic hardware, alignment, hinges.Leaks & BuildingTrace water paths, roof vs condensate, damage control.Preventive MaintenanceRoutines that catch failures before they become calls.

BuildingWrench covers routine facility work and tells you where to stop. Regulated electrical, refrigerant, gas, life-safety, and structural work always requires a qualified professional.

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