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10 Warning Signs Your Furnace Needs to Be Serviced

furnace warning signs

Originally Published September 25th, 2017; Last Updated October 23rd, 2021

Colder days are coming, which means Portland homeowners will be running their furnaces more often. Referencing Murphy’s Law, if a piece of equipment can break, chances are that if its maintenance isn’t up-to-date, it will. Before you find yourself suddenly stuck in a cold house this winter, keep an eye out for the following warning signs your furnace needs repair.

1. Increase in Energy Bills

Have your energy bills gone up drastically compared to the same time last year? If so, it might be time to repair or replace your furnace. A professional service appointment can provide appropriate fixes to increase energy efficiency and reduce heating costs.

2. Date of Last Furnace Service

If this question has you scratching your head, there’s no better time than now for an annual furnace maintenance appointment. Being proactive with service appointments can help prepare your furnace for the season. Service options could include the following:

  • Annual tune ups
  • Troubleshooting common issues
  • Emergency furnace repairs

3. A Yellow Pilot Light

The pilot light that runs inside the furnace should be a clean, bright blue color. If it looks yellow, that could be a sign that your furnace has a carbon monoxide leak. This is a highly poisonous gas, so it’s important to have it checked out by an experienced technician right away.

4. Excess Dust Near Furnace Vents

When was the last time you changed the filters in your furnace? Filters help the unit catch dust and keep the air clean. When they’ve been in use for longer than you can remember, you might notice dust buildup around the vents. When this happens, your indoor air quality can decrease. If you can’t remember when you last changed the filters, now is a good time.

5. Looks Dated

If your furnace simply looks old and worn out, it’s probably due for an in-depth tune-up or replacement. An experienced team of heating and cooling experts can take a closer look and provide you with a proper solution to keep your furnace in peak condition. Typically, a furnace has 15-20 years of useful life. If you haven’t replaced yours since the 90s, it might be time to start thinking about an HVAC upgrade.

6. Strange Noises

Those pops, squeaks, and creaks you hear coming from the furnace might be a warning sign that something is out of place. A piece inside may have gotten loose, so it’s important to have the unit checked out by a trained professional. It often just takes a simple tightening of all the bolts to set it back to normal.

7. House Takes Forever to Heat Up

Have you noticed that it takes longer for your home to heat up, especially in Portland’s winter months? If so, your furnace might be working harder than it should be. This is a good time to call your local heating and air conditioning experts to make sure there isn’t a larger problem at hand.

8. Old Thermostat Batteries

If your furnace simply doesn’t work, it could mean that your thermostat batteries died. The two units are connected, so without proper battery power, your furnace won’t get the cues it needs to run properly. Changing the batteries is an easy fix. However, if new thermostat batteries don’t solve the problem, it’d be time to schedule a service appointment.

9. Frequent Cycles

A working furnace regulates the temperature in your home by turning on when it senses that the air is too cold. A malfunctioning furnace is often indicated by frequent cycles. Some causes of this activity include:

  • Overheating
  • Oversized furnace
  • Thermostat malfunctions

If this problem continues, it can cause permanent damage to the unit, not to mention higher heating bills over time.

10. Furnace Won’t Turn On

When your unit won’t startup, there are several ways to troubleshoot your furnace to identify potential problems. Try the following simple checks before calling in the experts:

  • Make sure the thermostat is on and set to heat.
  • Check that the furnace fan works.
  • Check the gas supply by testing other gas appliances in your home.
  • If your furnace has a pilot light, double-check that it’s still ignited.

Your Portland, OR Furnace Experts

Some simple furnace repairs can be done by homeowners, but the technical fixes should be left to highly-trained technicians. If your furnace seems to have a larger problem than you can handle yourself, give Jacobs a call at 503.234.7331. Or, contact us with your info and furnace problem, and we’ll be happy to help.

About the Author

Amanda Jacobs portrait

Amanda Jacobs, Internal Project Manager

Amanda Jacobs is an Internal Projects Manager and 3rd generation member of Jacobs Heating & Air Conditioning. She received her MBA from Seattle University and has worked for a leading HVAC training and consulting firm. When not talking HVAC on the Jacobs Blog, you can find her on the golf course or whipping up her famous vegan chili.