Oil Furnace Ignition Repair & Transformer Replacement

Ignition Repair

Furnace Won't Ignite? We Can Help

A furnace that will not ignite is one of the most common no-heat calls we get. Modern furnaces have a built-in warning system, and a flashing light usually means the furnace is locked out. The cause is often a fouled or cracked igniter, or a failed ignition transformer.

This is hazardous work involving high voltage and fuel, so we strongly recommend leaving it to a licensed technician. Call us any time, day or night, and we will diagnose and fix the ignition fault safely. Need a simpler igniter fix? See our igniter repair page.

Schedule Service Call (631) 779-3196

24/7 Emergency Oil furnace ignition repair on Long Island

Common Causes

What Causes Ignition Failure

Three components are behind most ignition problems.

The most common ignition faults we find are:

Spark igniter failure — usually from cracks in the ceramic base or a build-up of dirt, dust, and oil. Light fouling can be cleaned, but a cracked igniter must be replaced
Hot surface igniter (HSI) failure — caused by contact with oil, too high an electric current, or simply reaching the end of its service life
Ignition transformer failure — the transformer converts voltage to create the spark. Like igniters, it can be damaged by moisture and leaked oil, and a failed transformer stops the burner from firing

Transformer

What an Ignition Transformer Does

A small part with a big job in your furnace.

The ignition transformer steps up voltage to create the spark that lights the fuel. Low-voltage transformers are typically found on the zone valves or thermostat circuit. When a transformer stops working properly, it can cause the igniter to fail and the furnace to lock out or overheat.

Replacing a transformer correctly means isolating power, confirming the fault, fitting the right replacement part, and testing for safe ignition. Our technicians carry common parts so most transformer replacements are completed in a single visit.

Our Process

How We Repair Ignition Problems

A safe, systematic repair, not guesswork.

What to Expect

Shut down power safely and read any lockout codes
Locate and inspect the igniter, electrodes, and transformer
Clean light fouling or replace cracked and failed components
Check related parts: filters, wiring, and the burner motor
Test for clean, reliable ignition before we leave

FAQ

Frequently Asked Questions

Answers Long Island homeowners ask us most.

1How can I troubleshoot an oil burner that won't ignite?

Check that the tank has oil, the thermostat is set to heat, and the power and emergency switches are on, then press the reset once. If it locks out again, stop, because repeated resets can be unsafe, and call a licensed technician to inspect the igniter and transformer.

2What causes the spark igniter to stop working?

Most often cracks in the ceramic base or a build-up of dirt, dust, and oil. Light fouling can sometimes be cleaned, but a cracked spark igniter needs to be replaced.

3What is an ignition transformer and what does it do?

It converts electrical voltage to create the high-energy spark that ignites the fuel. If it fails, often from moisture or leaked oil, the igniter cannot spark and the furnace will not start.

4Should I replace an ignition transformer myself?

No. It involves high voltage and fuel safety. A licensed technician can isolate power, confirm the fault, fit the correct part, and test for safe ignition. We offer 24/7 service across Long Island.

5Do you serve all of Long Island?

Yes. We serve Suffolk County, Nassau County, and parts of Queens with the same licensed, local team.

6Are you licensed and insured?

Yes. Domino Fuel is fully licensed and insured, and has served Long Island since 1981.