A radiator that will not heat usually has a local cause: a stuck steam air vent, a closed or failed valve, or air trapped inside a hot-water radiator. If only one radiator is cold, the repair is often at that radiator. If many radiators or the whole building are cold, the cause is usually upstream at the boiler or in the piping. A radiator that is leaking, banging or hissing has its own set of likely causes, covered below.
NP Co. repairs radiator valves, vents, leaking connections and heat-distribution problems in steam and hot-water systems across Manhattan, Brooklyn, Queens, the Bronx and Staten Island. If we find the problem is the boiler rather than the radiator, we say so plainly and point you to our boiler repair service.
Common in older NYC buildings. Steam rises from the boiler to each radiator, pushing air out through a vent. They typically have a single supply valve and an air vent. Common problems are a clogged or failed vent, a valve that does not fully open, banging from trapped water, and leaks at the valve packing or union.
Heated water is circulated by a pump through baseboard or radiator units. They often have a bleeder valve at the top. Common problems are trapped air, a stuck valve, an unbalanced system where some radiators heat more than others, and leaks at valves or connections.
A radiator that stays cold while others in the same apartment are warm often has a stuck or closed valve, or on a steam system a vent that is clogged with debris or has failed. Steam cannot enter a radiator if the air inside has nowhere to go, so a failed vent leaves it cold even though the boiler is working.
A radiator that is hot at the bottom and cold at the top points to air. On a hot-water radiator the air is trapped and must be bled. On a steam radiator, the same pattern usually means the vent is not releasing air quickly enough for steam to fill the unit.
Banging or knocking in a steam system usually means condensate, which is water, is trapped somewhere and being hit by steam. A radiator that is not sloped back toward its supply valve is a classic cause, as is a valve left partly open. Sagging pipes can also hold water. Fixing the pitch or the valve solves the cause rather than just the noise.
Hissing or spitting from a steam vent is normal for a moment as air escapes, but constant spitting or water from the vent suggests the vent has failed or the system is carrying too much water. A leak at the valve usually comes from a worn packing nut or a loose or corroded union, both of which are plumbing repairs.
Repair or replacement of radiator supply valves that are stuck, leaking at the packing, or no longer opening fully.
Replacement of failed steam vents and bleeder valves, so radiators fill with heat and release air properly.
Repair of leaks at unions, valve connections and short pipe connections where the radiator meets the piping.
Correcting a radiator that is not sloped properly, one of the most common causes of banging in steam heat.
If a radiator itself is cracked or badly corroded, small repairs are not enough. We will tell you honestly when the unit needs to be addressed differently, and what the practical options are.
Radiators are the visible end of a heating system, but the cause often sits elsewhere. A single cold radiator is usually a radiator-level problem. Several cold radiators, or no heat anywhere, suggests the boiler, a pump, a pressure problem or a distribution issue. If you notice a boiler pilot that will not stay lit, a pressure warning, or no hot water as well, start with our boiler repair page instead.
If the issue is no hot water at the tap rather than no heat in the rooms, that is a different system. See our water heater service. Tell us what is actually happening when you call, and we will point you to the right diagnosis before anything is repaired.
Place a towel and a shallow pan under the leak and keep furniture and rugs away from it. If the leak is at the valve and you can safely turn the radiator valve off, do so. On a steam system, do not open vents or unions yourself, because the radiator can be hot and under pressure. If water is spraying, spreading, or reaching the unit below, call right away.
A small, steady drip is still worth fixing quickly. It can rot flooring and damage ceilings below, and it often points to a worn part that will not improve on its own. If you are not sure where the water is coming from, our leak detection service can trace the source, and urgent water problems can go to emergency plumbing.
We confirm whether you have steam or hot-water heat and how many radiators are affected.
We check the valve, vent, pitch and connections, then the supply side if the radiator itself is not the cause.
You get the price for the repair before the work begins.
We complete the repair and confirm the radiator heats and holds without leaking.
Many NYC apartments are heated by a central boiler through steam or hot-water risers that serve several units. That means one apartment's cold radiator can be a local problem or part of a building-wide one, and repairs sometimes involve a shared system. We coordinate with building management or the super rather than a single occupant when the work affects more than one unit.
NYC's legal heat season runs from October 1 through May 31, and cold snaps tend to bring a flood of heating calls at the same time. If a radiator has been behaving strangely, it is cheaper and easier to deal with it early. If your building has no heat, report it to your landlord or building management as well, and call us if you are responsible for the building or need plumbing repair.
A single vent or valve replacement is usually the simplest radiator repair. The scope grows when the system has to be drained, when valves are seized or corroded, when pipes have sagged, or when the cause turns out to be upstream. Older systems can reveal a second problem once the first is fixed, which we explain as we find it.
System type also matters. Steam radiators depend on proper venting and pitch, while hot-water radiators depend on air removal and balanced flow. For the heating equipment itself, see boiler repair. For general questions about our services, visit all plumbing services.
Building types and heating systems differ from borough to borough. Local pages: Radiator Repair in Manhattan, Radiator Repair in Brooklyn, Radiator Repair in Queens, Radiator Repair in the Bronx, and Radiator Repair in Staten Island.
Steam and hot-water radiators across all NYC boroughs — valves, vents and leaks.
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