What To Do If Furnace Stops Working

San Rafael

(415) 942-6565

Santa Rosa

(707) 452-3464

Is the furnace not working? Most people do not know when their furnace is not operating correctly until they try to use it. Having no working furnace in your house can be a catastrophe when the weather is cold, and the home can’t be heated. However, it is possible that the problem may not require any extensive and costly repairs. Furnaces have many working parts that can go wrong at any time, whether a problem with the vents, the pilot light, the thermostat, or even the power switch. A lot of the time, a faulty furnace can be remedied through some basic troubleshooting that you can easily perform on your own.

In this article, we will go over the possible problems you might be experiencing with your furnace, as well as some possible reasons they are occurring and how to fix them so that you are able to have hot air in your chilly home once again. We also cover a few signs that your furnace may be seriously malfunctioning and need professional repair. If your furnace stops working as it should, read on to find out how you can possibly get it back to heating your home properly all by yourself!

Possible Furnace Air Flow and Temperature Problems

Among the common furnace problems you may be experiencing that can possibly be remedied with DIY troubleshooting are:

Furnace not producing heat – This would be the biggest and most obvious problem. Your furnace may not be giving you enough hot air flow, or perhaps not hot at at all.

Rapid cycling – Your furnace may be turning on and off during a cycle at extremely fast rates while struggling to heat your home.

Loud noises – You may be hearing loud rattling, squeaking, or rumbling sounds any time you run the furnace system.

Low Airflow- If your system is not putting out enough airflow, your home will never reach desired temp.

Why Are These Problems Happening With Your Gas Furnace?

There could be many different reasons why your furnace is malfunctioning, but some possible reasons that you could identify include:

Furnace producing no heat: This could be an indication of a dirty filters or gas burner. It could also mean that your thermostat is not set to heat mode or that it needs to be adjusted to the correct temperature. Another factor of this problem might be that the furnace vent is blocked.

Strange cycling patterns: A furnace shutting on and off rapidly could indicate that you need a filter replacement. It could also mean there are problems with the blower motor, meaning that the belts need tightening or parts need oiling.

Noisy furnace: If your furnace is making strange noises, it could mean there is a blower belt or motor that is slipping if the sound is high-pitched, or that a gas burner is dirty if the sound is more low-pitched.

Low Airflow: Low airflow can be caused by a dirty filter, closed dampers or even leakage in your ducting. If you switch out a filter for a new one, it can be surprising the additional airflow your system puts out. Closed dampers can also restrict airflow to the home from the furnace, it is important to switch any dampers to the open position. In the worst situations, your furnace problems can be caused by the air handler itself and may need a replacement.

How You Can Troubleshoot Your Heating And Cooling System

There are cases when you will need a professional technician come and work on your furnace system, but there are many ways you can check to see what the problem is yourself, or even fix the problem yourself. Here are all the things to watch out for and troubleshoot if you are having trouble with your furnace.

1) Thermostat

Check your thermostat to make sure it is set on the heat setting and that it is five degrees above room temperature. The thermostat should be set a few degrees above room temperature so that the furnace can know to run long enough to adequately warm the living area. It is also a good idea to check the thermostat batteries and replace them, if you have a battery-operated thermostat. Also make sure there is no dust within the thermostat when you open it up (gently blow away any debris that may be inside), and that it is properly attached to the wall.

2) Circuit breaker

The next thing to check is whether a circuit breaker or fuse tripped or blew. If a circuit breaker or fuse is out, it could be shutting off power going to the furnace. You should also check that the power switch to the furnace is even turned on (will look like a standard wall switch near the furnace). Even if you have a gas furnace, it still needs electricity to run. It is good to double check the power to make sure nothing accidentally got shut off and that the breakers and fuses are working properly. Another thing you can do is double check that the safety switch for the furnace is (located on the furnace door) is off.

3) Filters

Filters are a common problem for many furnaces if they are not changed regularly. Locate your furnace filter and make sure that it is cleaned. Large amounts of dirt and debris can lead to a clogged filter, which can be the cause of the furnace not providing adequate warmth to your home. It may be that you need to replace your furnace filter, which should be done regularly in order to avoid any extreme debris buildup that could cause the heat exchanger to overheat. If a heat exchanger can’t transfer hot air, that will cause serious problems with trying to provide warmth to your home. Depending on your heating system, the filter will be located in a different place, so be sure to consult an owner’s manual to find where yours is.

4) Gas Valves

Like with the breakers, it is possible the gas valve could have gotten turned off. Make sure the handle is in the correct position to ensure the gas line is on and providing gas to the furnace, and also make sure that the pilot light is on. The standing pilot light is the ignition source of a gas furnace so be sure that it is lit and blue in color. You can check this light by removing the front panel and burner cover on the furnace. Also take a look at the furnace burner flames. If they are not blue, it is possible that your burners need cleaning. This is especially important to check after the summer season is over and you are preparing to use your furnace in the cold season, since dust can buildup over long periods of non-use. The furnace pilot light should be blue in color as well. Follow safety procedures in your owner’s manual.

5) Drain lines

Drain lines within a furnace can sometimes have some amount of gunk and mold growth depending on how much water is drained off from the unit during heating season. To fix the problem, you can wash the drain hose with bleach and water to rinse dirt and grime out.

6) Oil the furnace blower

In preparation for heating season, it can be a good idea to oil the furnace blower motor to make sure all of the parts are well lubricated and run more smoothly. Turn off the power to the furnace and remove the access panel. Detach the blower motor from the assembly and locate the blower motor lubrication ports, where you will pour a couple drops of oil into. Replace all the parts and be sure the front panel over the motor is secure so that the furnace can run properly.

7) Ducts

It is possible that your air ducts may be either leaking, or blocked from debris buildup. Seal any gaps between duct sections with metal duct tape. It is also recommended to perform routine duct cleaning every year before heating season starts in order to clear out all debris and sediment buildup that can happen in the ducts over a period of little to no use.

8) Vents

Check your outdoor intake and exhaust vents to be sure nothing is blocking them and that the pipes are covered with a mesh hardware cloth rather than a window screen mesh. Clear away any debris, like leaves, dirt, or snow that could be creating a blockage over or in the vents. Also clear away debris from the outdoor compressor unit if you have a heat pump.

When It Requires More Than A Furnace Filter Change, Call a Pro.

Though furnace troubleshooting can be done on your own in many cases, there are instances where a you will need a furnace repair technician to help you out with you malfunctioning heating and cooling system. Below are the warning signs that you have a broken furnace that needs to be repaired.

You’ve tried all of the above

You’ve changed the air filter, checked that the thermostat is set to the right temperature, that the breaker switch is on, that your air ducts are clean, and your pilot light is operating normally. But still your home is not getting any proper amount of heat. If you’ve gone through each of the checks in the list above and find your furnace is still giving you problems, that could mean it’s time to call in a professional if you want to have a warm house as soon as possible.

You can’t turn the furnace on at all.

This means there is definitely a bigger problem if the unit is not doing anything at all when you attempt to start it up. You will need a technician to solve the problem since this most likely is not an easy fix.

You need more serious duct cleaning.

Even if you keep up regularly with duct cleaning, dirt and debris buildup can becomes a serious problem that may possibly require the expertise and equipment of a professional.

You have an old furnace.

If your furnace is old enough, it could have passed the warranty period and may be wasting significant money and energy while not getting any significant warm air in your home. In this case, it might be time to consider a new system.

You hear grinding noises

A strong sign of a broken furnace. This noise in particular could mean that the motor bearings need to be repaired and that it is time to call a professional.

You have a gas leak.

If you smell gas in your home, leave the house immediately and contact a professional to have an emergency service done as soon as possible. You should call a professional for any major gas line related issue in your heating system.

Do Not Ignore The Warning Signs, Call John Owens Services Today!

Remember, you can always call on John Owens Services if you think you need assistance with a serious furnace problem. We are an experienced HVAC contractor when it comes to any kind of furnace maintenance, repair, or installation. All you have to do is contact us by phone or via an online form, and we can send one of our available technicians out to your house to dive deeper and diagnose the problem before getting right to work on fixing it, often on the same visit! If your furnace or thermostat stops working, don’t hesitate to reach out to us when the troubleshoot tips don’t solve the problem.

Having a non-operating furnace is no joke. Heat is essential to your home during the winter season, especially depending on where you live. You may have problems that require the assistance of a professional HVAC technician, but it is also very possible to remedy the issue yourself if you troubleshoot using the advice listed in this article. There are many ways you can safely repair your furnace or thermostat yourself if you find one of the above mentioned problems applies to you, and you follow all instructions in your owner’s manual when dealing with dangerous materials. Don’t live in the cold! Keep your home warm this winter with these DIY furnace repair tips when your furnace stops working.

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San Rafael
(415) 942-6565
Santa Rosa
(707) 452-3464



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San Rafael
(415) 942-6565
Santa Rosa
(707) 452-3464