My boiler stopped working and there's no heat in my Centereach house. What should I check first, and who do I call?

First: when it's not a boiler problem at all

• You smell gas, hear hissing, or a carbon monoxide alarm goes off. Get everyone out and call 911 or National Grid's Long Island gas emergency line, 1-800-490-0045, from outside. Our guide on what to do if you smell gas in Centereach has the full steps.
• No gas at any appliance. If the boiler, stove and water heater all have no gas, National Grid counts that as a gas emergency too, along with flames that are abnormally high or low on every appliance and water continuously leaking from a gas boiler or water heater. Report it to National Grid rather than a contractor.
• No power in the house. Gas and oil boilers both need electricity for the burner, controls and circulator pump, so a power outage means no heat. Report outages to PSEG Long Island online, through its outage map, or at 1-800-490-0075.

The checks to do before you book a repair

1. Thermostat. Set it to Heat and a few degrees above the room temperature. If the screen is blank or dim, replace the batteries.
2. Emergency switch. Most boilers have a switch that looks like a light switch, often at the top of the basement stairs or on the wall near the boiler (frequently with a red plate). It's easy to flip off by accident. Make sure it's on.
3. Breaker. Check the electrical panel for a tripped breaker labeled boiler, burner or heat. Reset it once. If it trips again, leave it off and have a contractor find out why.
4. Fuel. On oil, read the tank gauge; an empty tank is a common first-cold-night problem, and the oil industry's own technician training warns not to assume a tank has oil just because the owner thinks it does. On gas, see whether a stove burner lights.
5. Water to the house. A water main break or SCWA work on your street can trip a hot-water or steam boiler's low-water safety and shut it down. If your taps are dry or sputtering, that may be why.

The oil burner reset button: once, at most

Oil burners have a primary control, usually with a red reset button, that shuts the burner off "on safety" when it doesn't sense a flame. The National Oilheat Research Alliance (NORA), which trains and certifies oil heat technicians, teaches that pressing reset doesn't fix anything, that a reset should never be pressed when there may be oil built up in the combustion chamber, and that a locked-out burner should never be reset over and over. Each failed start can spray more oil into the chamber, and a delayed ignition is the most common cause of a puff-back that can blow soot through the house.

So press it once. If the burner doesn't start and stay running, or you smell oil or see smoke, stop and call a technician. Many newer controls also limit resets on purpose and lock out after a few tries.

Signs it's a repair, not a setting

• The burner won't start after the checks above, or the reset trips again.
• Oil smell, smoke or soot near an oil burner.
• Water leaking around the boiler, or the relief valve on the side of the boiler is dripping or discharging (it opens at the pressure stamped on it, usually 30 psi on homes).
• The boiler runs and gets hot but the radiators or baseboards stay cold (often a circulator pump, a zone valve, or air in the lines).
• Only some rooms or one floor are cold on a zoned system.
• On a steam boiler, the water sight glass is empty. Turn the boiler off and let it cool; adding cold water to a hot, dry boiler can crack it.

Leave covers, controls and safety switches alone. Before anyone works on your system, check their Suffolk County license with our guide on how to check a plumber's license. Gas-side work after a shutoff can also need National Grid's Task 87 qualification, explained in the gas guide linked above.

While you wait: keep the pipes from freezing

A house without heat in a Long Island cold snap can freeze pipes, especially on outside walls and in crawl spaces. Open cabinet doors under sinks on outside walls, let a cold tap drip, and never use an oven, grill or outdoor generator indoors for heat. New York's Executive Law § 378 requires a working carbon monoxide detector in one- and two-family homes with a fuel-burning appliance or attached garage, so make sure yours works. Our guide to winterizing outdoor faucets and pipes on Long Island covers the rest.

Help paying for a broken boiler or fuel (Suffolk County)

New York's Home Energy Assistance Program (HEAP) has several pieces that matter when the heat goes out. All of them are applied for through your HEAP Local District Contact, which for Centereach-area homes is the Suffolk County Department of Social Services (HEAP line 631-853-8825; there's also a DSS center at 80 Middle Country Road in Coram, and the Suffolk County Office for the Aging is an alternate certifier).

• Heating Equipment Repair and Replacement: for income-eligible homeowners age 60 or older who live in the home. It covers the actual cost to repair or replace a furnace, boiler or other primary heating equipment, up to $4,000 for a repair and $8,000 for a replacement. The 2026-2027 benefit opened October 1, 2026. The work must be approved by HEAP before it starts, and payment goes directly to a participating vendor.
• Clean and Tune: one cleaning and tune-up of primary heating equipment for income-eligible homeowners, up to $500, which can include minor repairs, chimney cleaning, a carbon monoxide detector or a programmable thermostat. Your equipment must be more than 12 months old, not cleaned in the last 12 months, and not covered by a service contract that includes cleaning. Opened October 1, 2026.
• Regular HEAP: help paying heating costs, scheduled to open November 2, 2026 for the 2026-2027 season.
• Emergency HEAP: for households out of fuel or below a quarter tank of oil or propane, or whose heat or heat-related electric service is off or scheduled to be shut off. For 2026-2027 it's scheduled to open January 4, 2027.

The 2026-2027 HEAP income limit is $3,563 a month for a one-person household and $6,852 for a household of four (gross). Check the state pages below for current amounts and rules before you apply.

Sources

• National Grid, Report a Gas Emergency (what counts as a gas emergency; Long Island number)
• PSEG Long Island, Ways to Report an Outage
• National Oilheat Research Alliance, Service Procedures (Silver Certification, Chapter 15), Primary Controls (Chapter 11) and Burner troubleshooting
• FDNY, Fuel-oil study material (delayed ignition as the most common cause of puff-back)
• New York State, Heating Equipment Repair or Replacement, Clean and Tune and Heating Assistance (HEAP)
• NYS OTDA, Suffolk County HEAP contacts
• New York Executive Law § 378(5-a) (carbon monoxide detectors)

Checked against National Grid, PSEG Long Island, NORA and New York State sources on Nov 2, 2026. HEAP dates and amounts change each season. In an emergency, follow 911 and National Grid over anything on this page.

Related services

• Emergency Plumber
• Frozen & Burst Pipes