Most furnace breakdowns come down to a short list of causes: a dirty or failed ignition part, an airflow problem, a safety switch doing its job, a worn motor, or a thermostat that is not telling the furnace what you think it is. Finding the real cause is the difference between a repair that lasts and one that brings us back in two weeks.
Call or text (781) 353-8852 and tell us what you are seeing. We are a family owned company with an A+ BBB rating and 50 years in business, and we will tell you honestly whether the furnace is worth repairing.
Before you call: a few quick checks
Some no-heat calls are fixed in a minute, and you will feel better knowing the basics are covered. If none of these helps, call us. If you smell gas or burning, or an alarm is sounding, leave the house first and call 911 or your gas utility from outside. Our no-heat checklist covers the full list.
Quick checks
- The thermostat is set to heat, the temperature is above the room temperature, and the display has fresh batteries if it uses them.
- The furnace switch (it looks like a light switch near the unit) is on, and the breaker for the furnace has not tripped.
- The filter is not packed with dust. A clogged filter can shut a furnace down on its high limit switch.
- Gas furnaces: other gas appliances such as the stove are working. Oil furnaces: the tank is not empty.
- Vents and registers are open and not blocked by furniture or rugs.
Signs your furnace needs repair
Blowing cool air
This can mean a failed igniter, a flame sensor that needs cleaning, or a safety lockout. It is one of the most common service calls.
Short cycling
A furnace that starts, runs a few minutes, and shuts off may be overheating from poor airflow or reacting to a sensor problem.
Loud or new noises
Squealing points to a belt or bearing. Banging at startup can mean delayed ignition, which should be looked at promptly.
Uneven heat
Some rooms warm and others stay cold. The cause may be a failing blower, blocked ducts, or a system that cannot keep up.
Yellow or flickering flame
On a gas furnace the flame should burn steady and blue. A yellow flame is a sign of incomplete combustion and needs prompt attention.
Soot or oil smell
On an oil furnace, soot around the unit or a persistent oil smell points to a burner problem.
Rising energy bills
A furnace that works harder than it used to is telling you something is off.
Water around the unit
Condensing furnaces make condensate. A leak means a clogged drain or a failed part.
Common furnace problems and what they usually involve
| Symptom | Likely cause | What the repair usually involves |
|---|---|---|
| No heat, fan runs | Igniter, flame sensor, or gas valve (gas furnaces) | Cleaning or replacing the part and testing the ignition sequence |
| No heat, nothing runs | Power, thermostat, or control board | Tracing the electrical problem and replacing the failed component |
| Turns off before the house is warm | Dirty filter, restricted airflow, or limit switch | Restoring airflow and checking that the heat exchanger is running within safe limits |
| Oil furnace stops and restarts | Nozzle, filter, or cad cell on the burner | Burner service, including nozzle and filter replacement and combustion testing |
| Loud blower | Worn motor or bearings, or a loose wheel | Replacing or rebalancing the blower assembly |
Heat exchangers are the part we are most careful about. A cracked heat exchanger on a gas furnace can leak combustion gases, and it is not something to patch. If we find one, we will show you what we found and explain your options.
What happens on a repair visit
- 1Listen firstWe ask what happened and when, because the story often points to the cause.
- 2Safety checkBefore we touch anything, we check for gas, carbon monoxide, and electrical hazards.
- 3DiagnoseWe test the ignition sequence, controls, airflow, and combustion instead of swapping parts and hoping.
- 4Explain and quoteYou hear what failed, what it costs to fix, and whether it is worth fixing on a furnace of this age.
- 5Repair and verifyOnce you approve, we make the repair and run the furnace through a full cycle to confirm it works.
Repair or replace: how to decide
A furnace that is around 15 years old with a major failure is usually a candidate for replacement. A younger furnace with a single worn part is almost always worth repairing. In between, the choice depends on the cost of the repair, the condition of the rest of the unit, and how much you have already spent. We will give you a straight answer, including when the answer is to keep the old one running another season.
- Repair cost. A common rule of thumb is to compare the repair to a fraction of replacement cost. If it approaches half, replacement deserves a serious look.
- Safety. A cracked heat exchanger or repeated combustion problems point toward replacement.
- Efficiency. Older furnaces can waste a meaningful share of the fuel they burn. A new one may pay back part of its cost over time.
- Your plans. If you plan to add central air or switch to a heat pump, it may be smart to plan the whole system together. See our furnace installation and replacement service.
Why choose Home Heating and Cooling
We have been fixing South Shore furnaces for 50 years, through more nor'easters than we can count. Our technicians know the gas and oil equipment that is common in Plymouth County homes, from newer condensing furnaces to older units that have been running since before the kids were born.
Because we are a family owned business, the person who answers the phone cares how the repair goes. We are rated A+ by the Better Business Bureau and open 24 hours a day, 7 days a week, so a no-heat call at 2 a.m. gets answered.
- A+ rated
- Better Business Bureau
- 50 years
- in business
- Family owned
- and operated
- Open 24 hours
- 7 days a week
Where we provide furnace repair
We serve homeowners across Plymouth County from our office in Norwell. These are some of the towns we visit most often. Every town page explains what is different about heating and cooling there.
- Rockland, MA
- Norwell, MA
- Hanover, MA
- Abington, MA
- Hingham, MA
- Whitman, MA
- Hanson, MA
- Pembroke, MA
- Scituate, MA
- Brockton, MA
- Hull, MA
- Marshfield, MA
Furnace Repair: common questions
Why is my furnace running but not heating the house?
The most common causes are a failed igniter or flame sensor on a gas furnace, a dirty filter restricting airflow, a burner problem on an oil furnace, or a thermostat issue. A technician can test each one and tell you which it is.
Do you repair both gas and oil furnaces?
Yes. Both are common in Plymouth County, and we service each. If you are unsure which fuel your furnace uses, we can tell you quickly on the call.
Is it safe to keep using a furnace that makes a strange noise?
It depends on the noise. A squeal may be a belt or bearing and is not an emergency. A bang or a smell of gas or fuel is different. Shut the furnace off and call us. If you smell gas, leave the house and call 911 or your gas utility from outside.
How can I keep my furnace from breaking down in winter?
Change the filter regularly and book a yearly tune-up in the fall. Most winter breakdowns start as small problems that a tune-up would have caught. See our maintenance service.
Can you come out at night or on weekends?
Yes. We are open 24 hours a day, 7 days a week. Call or text (781) 353-8852.
Should I have carbon monoxide detectors?
Yes. Massachusetts fire safety rules call for working carbon monoxide alarms in homes, and they matter most when fuel-burning equipment is running. Test them regularly and replace them on the schedule the manufacturer gives.
