01 / The short answer
Most "dead" furnaces are not broken. They are waiting for something you can give them in ten minutes.
Carrier's own troubleshooting page says a furnace that is not turning on is most often caused by a tripped breaker, a thermostat set wrong, a dirty air filter or the furnace power switch being off, and only after those by an ignition fault, a failed flame sensor or an interruption in the gas supply. Trane's page lists the same causes in nearly the same order (human error, a faulty thermostat, a tripped breaker, airflow, gas supply or valve, a faulty igniter), and Bryant's technician calls thermostat settings, a tripped breaker and a clogged filter the usual suspects. Three manufacturers, one list. That list is the first half of this page.
The second half is what the manufacturers do not write for New Jersey: what to do when the house smells of gas, what a tenant is owed when the heat is out, which repairs need a permit and which do not, what the national cost guides say a repair runs and why North Jersey labor costs more than their averages, and the one rule that keeps a cheap fault from becoming an expensive one: reset once, then call.
Set to Heat, with the set point above the room temperature. Carrier says 3 to 5 degrees above; Trane says replace the batteries if it has them.
A light-style switch on or near the furnace, and the breaker marked Furnace or Heat. A tripped breaker sits in the middle: off, then on, once.
Gray and packed means replace it, arrows pointing toward the furnace. A choked filter overheats the furnace and a safety switch shuts it down.
The valve handle on the gas pipe should line up with the pipe. If the stove and water heater are also out, call the utility, not a contractor.
Do the four checks, reset the furnace once, and stop. A furnace that locks out a second time is protecting itself from something a reset cannot fix, and every reset after that burns the part that is left. Write down what the furnace does when you call for heat (clicks, hums, lights, nothing) and the pattern of the status light if there is one; that sentence shortens the repair.
02 / Before any check
Two things come before troubleshooting: the smell of gas, and a carbon monoxide alarm.
If you smell gas, do not touch the furnace, a light switch or the phone inside the house. PSE&G's instruction is exact: leave the building immediately, get at least 350 feet away, and only then call PSE&G at 1-800-880-PSEG (7734) or 911. There is no charge for reporting a suspected leak, PSE&G says its technicians respond to gas-leak emergencies within 60 minutes, and it warns not to rely on your nose alone, because the odorant can be weak or absent even when gas is leaking. A furnace that "won't turn on" because its gas valve is doing its job is not a repair question until the utility has cleared the house.
If a carbon monoxide alarm sounds, get everyone out, including pets, and call 911 from outside. New Jersey requires carbon monoxide alarms in every one- and two-family home that contains a fuel-burning appliance or has an attached garage, installed in the immediate vicinity of the sleeping areas (N.J.A.C. 5:70-4.19). A gas furnace is a fuel-burning appliance. If your house does not have one near the bedrooms, that is the first thing to fix after the heat, not the last.
Burning smells, visible scorching on the cabinet, water pooling under the furnace or a breaker that trips again the moment it is reset also end the home check. Turn the furnace switch off and call.
03 / The ten-minute check
Eight checks, in the order the manufacturers put them, with what each one proves.
- Thermostat mode and set point. It must say Heat, not Off, Cool or Fan, and the set point must be above the room temperature. Carrier's rule of thumb is 3 to 5 degrees above. If the fan runs when you switch the fan to On but no heat ever comes, the thermostat is talking to the furnace and the problem is at the burner, which is a later step.
- Thermostat power. A blank screen is a dead thermostat, not a dead furnace. Trane's page says replace the batteries if the thermostat uses them and check for loose wiring if it is hard-wired. Some programmable models show an error code; the owner's manual decodes it.
- The furnace switch. Carrier describes it as a switch that looks like an ordinary light switch, mounted on the side of the furnace or on a nearby wall. It gets bumped by a laundry basket, a contractor or a child more often than anyone admits. It must be on.
- The breaker. At the panel, find the breaker labeled Furnace or Heat. A tripped breaker rests in the middle position. Carrier's instruction is to push it fully off and then on. If it trips again, stop: a breaker that will not hold is an electrical fault, and MDL's breaker keeps tripping guide explains why resetting it a third time is the wrong move.
- The filter. Bryant says replace it if it is gray or clogged with debris. Carrier explains the mechanism: a clogged filter restricts airflow, the heat exchanger overheats, and a safety switch shuts the furnace down. Turn the furnace power off, open the filter cabinet on the side or bottom of the furnace, slide the old filter out, slide the new one in with the arrow pointing toward the furnace, close the door, restore power. In an older Essex County house with a single return in the hall, the filter clogs faster than the box says.
- Vents and returns. Trane's page asks for one more airflow check: no couch, rug or curtain over the supply registers or the return grille. Closing registers in unused rooms does not save fuel on a forced-air furnace; it raises the pressure the blower works against.
- The gas. Carrier's step: make sure the gas valve on the pipe feeding the furnace is open (the handle in line with the pipe), and if other gas appliances such as the stove or water heater are also not working, the problem is the gas supply, and the utility is the call. Do not open the cabinet to look at the burners.
- The door and the drain. Most modern furnaces will not run with the blower door off or loose, because a door switch cuts power; push it closed until it latches. A high-efficiency furnace (a white plastic vent pipe instead of a metal flue) also has a condensate drain and often a float switch that stops the furnace when the drain backs up; a dry trap or a plugged line in a damp basement is a common winter shutdown, and clearing the drain line is a job for someone who has done it before.
If the furnace starts after any of those eight, you have found the cause, not necessarily the fault. A filter that choked in six weeks, a breaker that tripped at all, or a drain that backed up all have reasons, and the reason is what a tune-up visit looks for. MDL's furnace tune-up page explains what that visit covers.
04 / Read the symptom
"Won't turn on" is five different problems. The furnace tells you which one.
Stand at the furnace, have someone turn the thermostat up five degrees, and listen through a full start attempt. The sequence on a modern gas furnace is: a click (the control board wakes), a small fan starts (the inducer, which clears the flue and proves draft to a pressure switch), a glow or a tick-tick-tick (the igniter), a whoosh (the burners light), and once the heat exchanger is warm the main blower pushes warm air. Where the sequence stops is the diagnosis.
| What you see and hear | What usually caused it | Home check or licensed call |
|---|---|---|
| Nothing at all. No click, no fan, no light on the board. | No power: thermostat, furnace switch, breaker, door switch, a blown low-voltage fuse on the control board, or a failed transformer or board. | Home check for the first four; the fuse, transformer and board are a licensed call. |
| Clicks, the small fan runs, then it all stops and tries again. | The pressure switch did not prove draft: a blocked or iced flue or intake pipe outside, a cracked hose, a plugged condensate line, or a tired inducer motor. | Look at the outdoor vent pipes for snow, leaves or a nest; everything else is a licensed call. |
| Igniter glows or ticks, burners light, then go out within seconds. Repeats a few times and locks out. | A dirty flame sensor is the classic cause; also a weak igniter, low gas pressure or a failing gas valve. | Licensed call. Cleaning a flame sensor is a short job for a technician; Bryant lists a dirty flame sensor among the usual causes. |
| Igniter never glows; the fan runs and nothing lights. | A cracked hot-surface igniter, or no gas reaching the valve. | Check the gas valve handle and the other gas appliances; the igniter is a licensed call. |
| Burners light and run, then the furnace shuts off before the house is warm, over and over (short cycling). | Overheating: a choked filter, blocked returns, a failed blower or a limit switch doing its job; sometimes a thermostat placed over a supply register. | Filter and registers at home; anything after that is a licensed call. |
| Everything runs, but the air from the registers is cool or cold. | Covered in the next section. | See below. |
| A status light blinks a pattern. | The board is reporting a code. The count and color of the blinks is printed on the inside of the blower door or in the manual. | Write the pattern down. Tell MDL. Do not clear it by cycling power more than once, because the code is the fastest route to the fault. |
Two of those rows are worth a second look because they are easy to mistake for a dead furnace. A flue or intake pipe that terminates low on the side of a house in Montclair or Maplewood ices or drifts shut in the first real storm, and the furnace that "died overnight" starts again when the pipe is cleared. And a flame sensor that has been in a furnace since the house was last sold is coated in a film that insulates it from the flame it is supposed to sense; the control board sees no flame, closes the gas valve for safety, and tries again. After a few tries it locks out. That lockout is the furnace being careful, not the furnace being broken.
05 / Runs, but blows cold
A furnace that runs and blows cold air is a different fault from one that will not start.
If the blower runs but the air never warms, the chain that failed is the burner chain, and most of the home checks above do not apply. Three things to rule out before calling:
- The thermostat fan setting. A fan switch set to On runs the blower all the time, including the long minutes when the burners are off. The air feels cold because it is room air. Set the fan to Auto and the blower will run only when the furnace has heat to deliver.
- The first minute. A furnace that has just lit moves cool air for a short while before the heat exchanger is warm. That is normal.
- The burners. Watch the sequence described above. If the burners light and drop out, the flame sensor or gas supply is the suspect. If they never light, the igniter or gas valve is. If they stay lit and the air still turns cold after a few minutes, the limit switch may be cutting the burners because airflow is poor (filter, returns, blower), which is also how a cracked heat exchanger can present. That last possibility is why an older cold-air furnace should be looked at rather than run.
A heat pump that blows cool air in heating mode is its own subject; MDL's heat pump repair page covers defrost cycles, auxiliary heat and the cold-weather behavior that homeowners mistake for a fault.
06 / The one-reset rule
Reset the furnace once. If it locks out again, the second reset is where the repair bill starts growing.
A modern gas furnace has a control board that counts failed ignition attempts and locks the furnace out for a set period to prevent raw gas from building up. Turning the furnace switch off for 30 seconds and back on clears the lockout. Carrier's guidance is to cut power at the switch or breaker before any reset. One reset is fair: a single dirty-flame-sensor trip, a gust down the flue, a thermostat glitch.
The second lockout is information. It means the fault is repeatable, and each further cycle runs the igniter (a brittle ceramic part that cracks with use), opens and closes the gas valve, and spins the inducer, while the house keeps getting colder. Homeowners who reset a furnace again and again on a Saturday night routinely turn a flame-sensor cleaning into a flame-sensor cleaning plus an igniter. Reset once, note what the furnace did, and call with that note.
07 / What the repair costs
What the national cost guides publish for a no-heat repair, and why New Jersey sits above their averages.
MDL does not publish repair prices, because the price is the part plus the labor to reach it, and neither is known until the furnace is diagnosed. What follows is what the public sources say, with their dates, so you can tell a fair quote from an inflated one.
HomeAdvisor's average furnace repair cost, with a typical range of $133 to $505, as reported on Carrier's repair-versus-replace page (read November 6, 2026).
Trane's furnace repair cost article (published September 11, 2024, last updated February 2, 2026): from a simple fix at the low end to a major component at the high end.
Inch Calculator's national range for a gas, oil or propane furnace repair; electric furnaces $50 to $300 (updated September 5, 2023).
Median wage for New Jersey heating and air-conditioning mechanics, May 2025, against $29.33 nationally (U.S. Bureau of Labor Statistics). That is pay, not a contractor's billed rate.
Swipe across the table to see every column.
| Part replaced | HomeAdvisor via Carrier (read Nov. 6, 2026) | PickHVAC, typical installed (May 25, 2026) | Inch Calculator (Sept. 2023) |
|---|---|---|---|
| Flame sensor | $150 to $250 | $120 to $250 (with the igniter row; $40 to $100 at the low end, half an hour to an hour and a half of labor) | $80 to $250 |
| Hot-surface igniter | $150 to $500 | $120 to $250 typical, $300 to $450 high | $175 to $300 |
| Control board | $200 to $600 | $350 to $750 typical, up to $1,500 | $300 to $650 |
| Gas valve | $200 to $600 | $350 to $700 typical, up to $1,400 | $675 to $1,300 |
| Draft inducer motor | $200 to $1,500 | Not listed separately | Not listed separately |
| Blower motor | $150 to $2,000 | $450 to $900 typical, up to $1,800 for variable-speed motors | $250 to $900 |
| Heat exchanger | $500 to $1,500 | $1,800 to $3,200 typical, up to $6,000 | $500 to $3,500 |
| Thermostat | Not listed | Not listed | $100 to $450 |
Read the spread, not the single number. PickHVAC states its assumptions as Midwest labor rates and standard access; the BLS puts New Jersey HVAC wages about 22 percent above the national median, and a contractor's hourly rate also carries the truck, insurance, licensing and the diagnostic visit. A flame-sensor cleaning in West Orange is still a small bill; a blower motor in a 1950s basement with the furnace boxed in by a later finished ceiling is not. Ask how the diagnostic visit is charged, whether it is credited against the repair, and whether the quote names the part.
Two rows deserve a note. A cracked heat exchanger is the one repair where the honest answer is often the furnace replacement conversation rather than the part, and the New Jersey furnace replacement cost guide has the published installed ranges. And a thermostat is the one part on the list that a homeowner can legally and sensibly replace themselves on a conventional furnace; the wiring diagram is in the box.
For scale, the maintenance visit that prevents most of this table is cheap: Bob Vila, citing HomeAdvisor, puts a furnace tune-up at $100 to $200 and a gas furnace tune-up at $80 to $170, with parts found during the visit running $100 to $600.
08 / Repair or replace
The $5,000 rule, applied to a furnace that just quit.
CBS News (June 24, 2026) describes a simple guideline homeowners can use as a first screen: multiply the system's age in years by the repair estimate. Over 5,000, replacement is usually the better long-term money; under it, repair. Its examples are a 12-year-old system with a $500 repair (12 x 500 = 6,000, so look at replacing) and a 7-year-old system with a $400 repair (2,800, so repair). CBS also says what the rule leaves out: a capacitor or thermostat is not a compressor or heat exchanger, a large bill on an otherwise reliable system does not automatically justify replacement, and newer equipment's efficiency can offset part of the cost over time.
For a furnace, apply it this way. A $200 flame-sensor-and-igniter visit on a 20-year-old furnace scores 4,000: repair it, and plan. A $1,200 blower motor on the same furnace scores 24,000: get the replacement quote before authorizing the motor. A cracked heat exchanger on anything older than its warranty is the replacement conversation regardless of the arithmetic, because the exchanger is the part that keeps combustion gases out of the house air. MDL will say which side of the line a furnace is on after the diagnosis, not before.
09 / Essex County winters
Why this page is written for a 1956 colonial in West Orange and not for the national average.
The federal numbers describe MDL's home town plainly. Half of West Orange's housing units were built in 1956 or earlier, and 13,390 of its 17,166 occupied homes heat with utility gas, against 2,369 with electricity and 571 with fuel oil (U.S. Census Bureau, American Community Survey 2020-2024, tables B25035 and B25040). The furnace that stopped is, more often than not, a gas furnace in a basement that was finished around it, in a house whose return ducts were sized for a smaller family.
The weather decides how urgent that is. At the NOAA climate station at Essex County Airport in Caldwell, the 1991-2020 normals give November an average of 44.4°F with a normal low of 35.4°F, December 35.4°F and 27.7°F, and January 30.6°F with a normal low of 22.9°F and 1,066 heating degree days, the coldest month of the year. A furnace that fails in the first week of November gives you a day to get it looked at. The same failure in the third week of January gives you an evening, and pipes in an unheated 1950s basement wall do not get a vote.
Two practical consequences. First, the most valuable hour of the heating season is the one spent on a tune-up in October, which is why MDL's furnace tune-up page exists. Second, if your house is one of the 571 on oil or runs a boiler rather than a furnace, the checks above change: an oil burner that will not start usually has a reset button on the primary control that may be pressed once, never repeatedly, and a boiler is covered on MDL's boiler service page.
10 / Permits, tenants, alarms
The three New Jersey rules that apply to a no-heat call.
Under N.J.A.C. 5:23-2.7, ordinary heating maintenance includes replacing motors, pumps and fans of the same capacity and repairing or replacing control devices for heating equipment. No permit, no inspection, for the motors, fans and controls in the table above; a heat exchanger is not on that list.
N.J.A.C. 5:23-2.17A classes replacing a warm-air furnace with a new one of like capacity as minor work: the township gets notice before the work starts, and the permit application is delivered within five business days of that notice.
In buildings of three or more units, N.J.A.C. 5:10-14.4 requires every unit of dwelling space to be kept at 68°F from 6 a.m. to 11 p.m. and 65°F from 11 p.m. to 6 a.m. from October 1 to May 15. One- and two-family rentals follow the town's housing code. Our advice to any landlord: treat a no-heat call as a same-day call.
N.J.A.C. 5:70-4.19 requires carbon monoxide alarms in one- and two-family dwellings with a fuel-burning device, in the immediate vicinity of the sleeping areas. A gas furnace is a fuel-burning device.
The tenant rule is the one most often misread in both directions. N.J.A.C. 5:10 is the state code for hotels and multiple dwellings, and 5:10-2.2 defines a multiple dwelling as three or more units, so the state rule covers the apartment building, not by itself the rental in a two-family house in Orange or Bloomfield; there the town's housing code and the lease set the heat obligation, and the local housing office can say what it is. A tenant with a furnace that will not start should do the thermostat, switch and breaker checks, then call the owner with the time and what the furnace did; the owner's next call is the repair.
11 / Before you call
Six details that turn a no-heat call into a one-visit repair.
The town and address, where the furnace is (basement, attic, closet), and anything in the way of the blower door and the panel.
Nothing, clicks, the small fan, the igniter glow, burners that light and drop out, cold air from the registers. One sentence from the table above.
The blink pattern on the control board, if there is a window, and the brand on the cabinet.
The thermostat setting, the breaker, the filter date, how many resets. Honest resets count; they explain a cracked igniter.
Gas, oil or electric; furnace, boiler or heat pump; a metal flue or white plastic pipes; the furnace's age if the label is readable without opening anything.
An infant, someone elderly or ill, or a tenant changes the urgency, and so does the forecast. Say so.
MDL Electric Cooling & Heating works from 4 Harrison Ave, West Orange, and holds New Jersey Master HVACR Contractor License #19HC00308200 and Electrical Contractor License #34EI01606200, which matters on a no-heat call more than people expect: a furnace that is dead because its circuit is dead is one visit, not two. MDL's site lists 24/7 electrical, heating and cooling help. Call 973.809.2339 for no heat, or use the request form below for a furnace that is limping along and needs a look this week.
12 / Direct answers
Furnace questions New Jersey homeowners search at eleven at night.
Why is my furnace not turning on?
Carrier's troubleshooting page puts the common causes in this order: a tripped circuit breaker, incorrect thermostat settings, a dirty air filter, or the furnace power switch turned off; the more complex causes are a faulty ignition system, a broken flame sensor or a disruption in the gas supply. Check the first four yourself. The last three are a licensed repair.
Why does my furnace click but not turn on?
The click is the control board calling for ignition. If the small inducer fan then runs and the furnace stops and retries, the pressure switch did not prove draft, which points to a blocked or iced vent pipe, a plugged condensate line or a tired inducer. If the igniter glows and the burners never light, the gas valve or supply is the suspect. If the burners light and go out within seconds, the flame sensor is the first thing a technician will clean. After one reset, the pattern is the diagnosis; write it down and call.
How do I reset my furnace?
Turn the furnace power switch (the light-style switch on or near the cabinet) off, wait about 30 seconds, and turn it on; Carrier's guidance is to cut power at the switch or breaker first. Some furnaces reset from the thermostat by switching it to Off and back to Heat. Reset once. A furnace that locks out again has a repeatable fault, and repeated resets wear the igniter and gas valve while the house gets colder.
Is a furnace that won't turn on an emergency?
It is an emergency if you smell gas (leave, get 350 feet away, call PSE&G at 1-800-880-7734 or 911 from outside), if a carbon monoxide alarm sounds (out of the house, 911), or if the house is at risk of freezing with the January normal low in Caldwell at 22.9°F. It is urgent, not an emergency, on a mild November day when the four home checks did not restore heat. MDL's site lists 24/7 heating help; say who is in the house and what the forecast is when you call.
What should I check before calling for furnace repair?
Thermostat set to Heat with the set point above the room temperature and fresh batteries; the furnace switch on; the Furnace breaker not tripped; a clean filter with the arrow toward the furnace; registers and the return grille uncovered; the gas valve handle in line with the pipe and the other gas appliances working; the blower door latched. Then one reset. Carrier, Trane and Bryant publish the same list.
How much does it cost to fix a furnace that won't turn on?
HomeAdvisor's average furnace repair is $318, with most repairs between $133 and $505 (as reported on Carrier's repair-versus-replace page). By part, the published ranges run from about $80 to $250 for a flame sensor and $120 to $500 for an igniter to $150 to $2,000 for a blower motor and $500 to $6,000 for a heat exchanger (HomeAdvisor via Carrier, PickHVAC May 2026, Inch Calculator 2023). New Jersey labor runs above those guides' assumptions: the BLS median wage for the state's HVAC mechanics is $35.79 an hour against $29.33 nationally. MDL prices after the diagnosis, not from this table.
Why is my furnace blowing cold air?
First check the thermostat's fan setting: On runs the blower constantly, including when the burners are off, so set it to Auto. The air is also cool for the first short while after ignition, while the heat exchanger warms up. If the air stays cold, the burners are lighting and dropping out (flame sensor, gas supply), never lighting (igniter, gas valve), or the limit switch is cutting them because airflow is poor (filter, returns, blower), which is also how a cracked heat exchanger can present on an older furnace. An older furnace that blows cold should be looked at rather than run.
Can a dirty filter stop a furnace from turning on?
Yes. Carrier explains that a clogged filter restricts airflow, the heat exchanger overheats, and a safety switch shuts the furnace down to protect it. The furnace may run for a few minutes and stop, or refuse to run at all after repeated overheating. Replace the filter with the airflow arrow pointing toward the furnace, reset once, and if it happens again within weeks, have the blower and returns checked.
Do I need a permit to repair my furnace in New Jersey?
Not for the usual no-heat repairs. N.J.A.C. 5:23-2.7 lists replacing motors, pumps and fans of the same capacity and repairing or replacing control devices for heating equipment as ordinary maintenance, which needs no permit. Replacing the whole furnace with one of like capacity is minor work under N.J.A.C. 5:23-2.17A: notice to the township first, permit application within five business days.
My landlord's furnace is out. What heat am I owed in New Jersey?
N.J.A.C. 5:10-14.4 applies to multiple dwellings, which N.J.A.C. 5:10-2.2 defines as buildings with three or more units. In those buildings, from October 1 to May 15 the owner must keep every unit of dwelling space at 68°F between 6 a.m. and 11 p.m. and 65°F between 11 p.m. and 6 a.m. In a one- or two-family rental the town's housing code and the lease set the heat obligation, so ask the local housing office what applies. Either way, do the thermostat, switch and breaker checks, then tell the owner the time and what the furnace did. The owner books the repair; the tenant does not open the furnace.
How long can a house go without heat before pipes freeze?
There is no safe published number; it depends on the outdoor temperature, the wind, the insulation and where the pipes run. The NOAA normals for Caldwell put January's average low at 22.9°F, and a pipe in an exterior wall or an unheated basement corner is at risk well before the living room feels cold. If heat cannot be restored the same day in freezing weather, open cabinet doors under sinks, let faucets on exterior walls drip, and keep interior doors open so warm air reaches the walls.
Should I replace a furnace that keeps breaking down?
Use the $5,000 rule from CBS News (June 24, 2026) as the first screen: age in years times the repair estimate, over 5,000 points toward replacement. Then weigh what CBS adds: the kind of repair (a sensor is not a heat exchanger), how often it has needed repairs, and the efficiency of a new unit. A cracked heat exchanger on a furnace past its warranty is the replacement conversation regardless; the New Jersey furnace replacement cost guide has the published installed ranges.
Does MDL repair furnaces in West Orange and Essex County?
MDL Electric Cooling & Heating is based at 4 Harrison Ave, West Orange, NJ 07052, holds New Jersey Master HVACR Contractor License #19HC00308200 and Electrical Contractor License #34EI01606200, and its site lists 24/7 electrical, heating and cooling help across North Jersey. The heating repair page covers the symptom-led path; the West Orange page covers the home town. Call 973.809.2339 or send the form on this page.
13 / Source record
Sources, read November 6, 2026
Every manufacturer step, price, wage, regulation and climate figure on this page was read from the source below on November 6, 2026. Prices are the sources' published national figures, not MDL quotes, and regulations are quoted as written on that date.
- Carrier — Your guide to a furnace not turning onCommon causes in order, the furnace switch, the breaker reset, the filter procedure and arrow direction, the gas valve and other-appliance check, cutting power before a reset.
- Trane — Troubleshooting guide: furnace not turning onThe six causes, thermostat batteries and wiring, registers and return vents, and the instruction to call a local HVAC company when the basics do not work.
- Bryant — Furnace not turning onThermostat settings, a tripped breaker and a clogged filter as the usual causes; replace a gray or clogged filter; the dirty flame sensor.
- Carrier — Furnace replacement cost vs. furnace repair costHomeAdvisor's $318 average and $133 to $505 range, and the per-part ranges for the flame sensor, igniter, control board, gas valve, inducer, blower and heat exchanger.
- Trane — Average furnace repair costPublished September 11, 2024, updated February 2, 2026: the $100 to $3,000 span.
- PickHVAC — Furnace parts replacement cost 2026Published May 25, 2026: low, typical and high installed ranges by part, labor hours for an igniter or flame sensor, and the Midwest labor and standard-access assumptions.
- Inch Calculator — Cost to repair a furnaceUpdated September 5, 2023: gas, oil and propane versus electric repair ranges and the per-part table.
- Bob Vila — Furnace tune-up costHomeAdvisor's $100 to $200 tune-up range, $80 to $170 for a gas furnace, and $100 to $600 for parts found during the visit.
- CBS News — What is the $5,000 rule for HVAC systems?June 24, 2026: the formula, the 12-year and 7-year examples, and the caveats on repair type, frequency and efficiency.
- PSE&G — I smell gasLeave immediately, 350 feet, 1-800-880-PSEG (7734) or 911 from outside, no charge for reporting, 60-minute response, do not rely on smell alone.
- N.J.A.C. 5:23-2.7 — Ordinary maintenanceHeating maintenance that needs no permit: motors, pumps and fans of the same capacity, and control devices for heating and air-conditioning equipment.
- N.J.A.C. 5:23-2.17A — Minor workReplacing a warm-air furnace with one of like capacity; the permit application within five business days of notice.
- N.J.A.C. 5:10-14.4 — Heating (multiple dwellings, three or more units per 5:10-2.2)October 1 to May 15; 68°F from 6 a.m. to 11 p.m. and 65°F from 11 p.m. to 6 a.m.
- N.J.A.C. 5:70-4.19 — Smoke alarms, carbon monoxide alarms and portable fire extinguishersCarbon monoxide alarms in one- and two-family dwellings with a fuel-burning device or attached garage, in the immediate vicinity of sleeping areas.
- U.S. Census Bureau via Census Reporter — ACS 2020-2024, tables B25040 and B25035, West Orange township17,166 occupied homes; 13,390 utility gas, 2,369 electricity, 571 fuel oil; median year built 1956.
- NOAA NCEI — 1991-2020 monthly normals, Essex County Airport, Caldwell (USW00054743)November, December and January average and minimum temperatures and heating degree days.
- U.S. Bureau of Labor Statistics — OEWS May 2025, New Jersey, heating, air conditioning and refrigeration mechanics and installers (49-9021)Median hourly wage $35.79 (series ending 08), median annual $74,450 (13); the national median hourly $29.33 (OEUN series 08).