Commercial Locksmith
A door closer is the hydraulic arm at the top of the door that pulls it shut at a controlled speed. When it slams, the sweep speed valve or the hydraulic damping has failed. When the door stops short of the frame, it is the latch speed valve, weak spring power, or a door that has drifted out of alignment. When there is oil on the unit or the floor, the closer is dead and has to be replaced. Most other complaints are a quarter-turn adjustment away from fixed.
Inside that metal box is a spring and a piston in hydraulic fluid. Opening the door compresses the spring; the spring then pulls the door shut while the fluid, metered through small valves, controls how fast it travels. That is the whole design, and it explains every symptom on this page: a wrong spring means the door lacks the strength to shut, and wrong fluid or valves mean it shuts at the wrong speed.
On a fire-rated door the closer is not a convenience item. It is the component that guarantees the door is shut when it matters, because a fire door propped or left ajar protects nothing.
The familiar box mounted on the door or frame with a jointed arm. Three common mountings - regular arm on the pull side, parallel arm tucked against the frame on the push side, and top jamb on the frame face. Parallel arm is the standard on out-swinging commercial doors because the arm is out of the way and harder to vandalize.
Hidden in the door or frame header, common in newer offices and lobbies. They work identically but cost more to service, because reaching the valves can mean pulling a cover or dropping the door.
Set into the floor beneath a pivot door, typical in glass storefronts and older lobbies. Durable and expensive, and they suffer here because water, road salt, and grit go straight into the floor box every winter.
Spring-loaded hinges that self-close an apartment entrance door without a visible arm. Cheap and common in walk-ups, and the usual failure is the spring simply going slack over the years, leaving a door that closes most of the way and stops.
The sweep speed - the main portion of the closing arc - is set too fast, or damping is gone. Check for oil first. A dry closer is an adjustment; a wet closer is a replacement. Slamming is worth taking seriously beyond the noise, because repeated impact loosens hinge screws, cracks frames, batters the lock, and eventually knocks the strike out of alignment.
The most reported problem, and the most misdiagnosed. Increase the latch speed - the last several inches of travel - and many doors start latching immediately. If not, the closer may be under-powered, or the real fault is mechanical: sagging hinges, a warped door, weatherstripping compressed too tight, a shifted strike plate. Our guide to a door that will not lock properly covers the alignment side.
Spring power is set too high, or the closer is oversized for the opening. This matters for access: ADA standards cap the opening force on interior hinged doors at 5 pounds, and a door an older resident or a child cannot push open is a door that gets propped, which defeats the closer entirely.
The seals have failed. Replace the unit. Beyond the lost damping, hydraulic fluid on a lobby floor is a slip hazard and on a painted door it is a mess that keeps coming back.
Almost always caused by someone forcing the door past its intended arc, or wind catching an entrance door on an avenue. On a hollow metal door the mounting screws pull out because the door was never reinforced behind the closer. The fix is a backing plate or sex bolts through the door, not longer screws into the same torn holes.
Check whether a hold-open arm has been engaged - a surprising number of service calls end there. Otherwise the spring has broken or the unit has failed outright.
In New York City multiple dwellings, apartment entrance doors and the fire doors that protect corridors and stairwells must be self-closing and self-latching. That is not a building preference - it is the reason a fire in one unit does not fill the only stairway with smoke. A door that has to be pulled shut by hand, or that stops an inch short of the latch, has effectively failed even though it still swings.
Two things follow. A broken closer on those doors is the repair to make this week, not next month, and a building can be cited for it. And never prop a fire door: wedges, bungee cords, chairs, and bricks are the most common cause of destroyed closers in the city, and they disable the protection at the same time. If a door must stay open for deliveries, use a hold-open device designed for it - on fire doors, one that releases on the alarm. See also fire escape door lock requirements in NYC and panic bar repair for NYC businesses.
Most surface closers have two or three small valve screws, usually under a plastic end cap and often labelled S for sweep, L for latch, and BC for backcheck. If you want to try before calling anyone:
We adjust, repair, and replace door closers on storefronts, offices, and residential buildings across Brooklyn, Manhattan, Queens, the Bronx, and Staten Island - including fire-rated openings that have to close and latch every time.
Adjust when the closer body is dry and intact, the arm is straight, the mounting is solid, and the door hangs true. Replace when fluid is leaking, the spring is broken, the body is cracked, the arm is bent, the mounting holes are torn out, or the unit is the wrong size - an under-powered closer on a heavy steel entrance will never latch reliably however it is tuned. Replacement is also the moment to correct a bad mounting and match the closer to the traffic the opening actually sees.
We quote per job after seeing the opening, because the price is driven by things you can check before calling: whether the fix is an adjustment or a new unit; the closer type, since a floor closer in a terrazzo lobby is a different job from a surface closer on an office door; whether the door is fire-rated, which dictates the hardware; whether the door needs reinforcement because the mounting tore out; whether hinges and strikes also need alignment work; and whether it is scheduled or after hours. Get the number before work starts, and see how to avoid locksmith scams in NYC if a price changes on site.
For tenants, the closer on your apartment entrance door and on every hallway and stairwell fire door is building hardware, and keeping it working is the owner's responsibility - report it in writing and keep the copy. Who pays for a locksmith, tenant or landlord covers where that line falls elsewhere. For owners, supers, and managing agents, the cheapest version of this job is a walk of the building twice a year: open every fire door, let it go, and watch whether it closes and latches on its own. Businesses should fold the same check into a closing routine, alongside how to secure your NYC storefront overnight.
The sweep speed valve on the closer has drifted, or the hydraulic fluid has lost its damping because a seal failed. If the closer body is dry, a small adjustment to the sweep valve fixes it in minutes. If there is oil on the closer, the door, or the floor beneath it, the unit is finished and needs replacing - no amount of adjustment restores damping in a closer that has lost its fluid.
Three common causes. The latch speed valve is turned down too far, so the door runs out of momentum in the last few inches. The spring power is too low for the door, common when a heavy door got a light closer. Or the closer is fine and the frame, hinges, or strike have shifted - a door that binds will not latch however the closer is set. Air pressure can also hold high-rise stairwell doors open.
No. Overhead closers are sealed hydraulic units, and once the seals fail the fluid leaks out and the damping goes with it. The leak also puts oil on the door face and the floor below, which becomes a slip hazard. Replacement is the only fix, and it is usually a straightforward swap when the mounting holes line up.
In New York City multiple dwellings, apartment entrance doors and the fire doors protecting hallways and stairwells are required to be self-closing and self-latching, and a door that has to be pulled shut by hand does not meet that standard. It is both a life-safety failure - these doors are what keep smoke out of the only stairway - and something a building can be cited for. Never wedge, prop, or bungee a fire door open.
A locksmith who works on commercial door hardware, because the closer is rarely the whole story - alignment, hinges, the strike, and the lock all interact, and swapping a closer onto a door that is out of square just moves the problem. Emergency Locksmith NY services and replaces door closers on storefronts, offices, and residential buildings across all five boroughs. Call (718) 412-1332.