How to Prep Your Furnace for Winter: A Homeowner’s Guide

Wondering how to prep your furnace for winter? Taking some simple steps ahead of time can save you from running into issues on the coldest day of the year.

Regular furnace maintenance helps your heating system run efficiently and reduces the risk of an unexpected breakdown. For gas and oil furnaces, inspection is especially crucial since combustion problems can create carbon monoxide risks.

Four Ways to Prepare Your HVAC System for Winter

1. Replace the Air Filter

Start with the air filter, typically located in the return-air duct or near the furnace cabinet. Check it every month during heating season and be sure to replace disposable air filters as soon as they look dirty.

Most disposable filters need to be replaced every one to three months. Clogged filters restrict airflow, which makes the HVAC system work harder and contributes to overheating. Clean filters help warm air move through the home, improving indoor air quality.

2. Clear Vents and Furnace Surroundings

Walk through your house and make sure that furniture, rugs or curtains aren’t blocking supply or return vents. If you notice dust on the registers, vacuum it away.

Keep boxes, cleaning supplies or other stored items away from the furnace, as well. Having a clear area reduces potential fire hazards.

3. Inspect Outdoor Intake and Exhaust Pipes

Many high-efficiency furnaces feature exterior intake and exhaust pipes, usually made from PVC. Check the openings from the outside and clear any leaves or debris.

Don’t take apart the piping or reach into damaged or hard-to-access vents; if you suspect a blockage or notice recurring snow and ice buildup, call an HVAC technician.

4. Test the Furnace Before Winter Arrives

In the fall, turn the furnace on for a short test run. Make sure that warm air reaches all the rooms and listen for unusual sounds like banging, rattling or grinding.

You might notice a dusty smell the first time the furnace runs after sitting idle, but it will fade quickly. However, a persistent burning, electrical or fuel odor demands professional attention. Same goes for a furnace that struggles to start, shuts down repeatedly or never reaches the thermostat setting.

Improve Energy Savings with Thermostat Settings

Setting the thermostat around 68 degrees is a good starting point when you’re home and awake. You can consider lowering it while you’re sleeping or away, as long as the temperature is comfortable for your household.

Programmable thermostats handle those changes automatically. Smart thermostats take it a step further by providing remote control, while some models can also learn your schedule over time to support energy savings.

If the wiring looks unfamiliar, leave the installation to a professional. Modern thermostats sometimes use additional wiring or controls that aren’t clear from the wall plate.

Check the Pilot Light and Electrical Supply

Older gas furnaces often use a standing pilot light. If yours goes out, carefully follow the manufacturer’s relighting instructions.

If you smell gas, leave the home right away and contact your gas utility or emergency services from a safe location. Do not relight the system on your own.

Also pay attention to the electrical supply, as a breaker that keeps tripping may point to a larger electrical issue that requires professional attention.

Protect Your Home with Carbon Monoxide Detectors

Fuel-burning furnaces can produce carbon monoxide when there’s combustion or venting challenges. Test your carbon monoxide detectors regularly and replace units that have reached their expiration date.

Install detectors at every level of the home, especially near sleeping areas, and test them monthly. Even with working detectors, annual furnace service is still important since an alarm can’t prevent a mechanical problem from developing.

When to Call an HVAC Technician

Call for service when you hear unusual noises, smell persistent burning odors or can’t get the furnace to heat normally. It’s always smart to leave gas valves, burners and internal combustion components to trained technicians.

If your furnace is blowing cold air, check the thermostat and filter first. If the problem continues, turn off the furnace and contact a technician. If you smell gas, leave the home immediately without operating electrical switches and contact your gas utility or emergency services from a safe location.

Professional Furnace Inspection Checklist

During annual service, ask your technician to inspect the burners, heat exchanger and electrical connections. High-efficiency furnaces should also have condensate systems checked. If a condensate line or trap needs professional drain cleaning, Mendel can address the blockage along with any related drainage issues.

Tune-ups also include thermostat testing, airflow checks, flame-sensor inspection and vent-pipe inspection. Scheduling this before it gets cold out gives you more time and flexibility to handle repairs before the furnace becomes essential.

Should You Consider a New Furnace?

Age is arguably the biggest factor in the decision to repair or replace a furnace. Frequent repairs, uneven heating and rising energy use also point to a system that’s nearing the end of its life.

One guideline is the “$5,000 rule.” Multiply your furnace’s age by the estimated repair costs, and if you end up with a number over $5,000, replacement could be more cost-efficient in the long run.

New furnace installation costs range widely, depending on the furnace type, size, efficiency, labor and accessibility. Higher-efficiency models generally cost more upfront, but if your repair bills are stacking up, ask for a replacement evaluation so you can compare all your options.

Our Plumbing and Heating Services

Before another frigid winter arrives, check your filter, clear your vents, inspect accessible outdoor pipes, test your furnace and verify your carbon monoxide detectors. These simple steps can help you handle heating season with fewer headaches.

Need a hand? Mendel Plumbing, Heating, Cooling & Electrical offers furnace maintenance, repair and replacement throughout the Fox Valley area. Same-day service is available, and transparent pricing is always provided upfront.

Our MendelCare Plan makes furnace maintenance easy with preventive maintenance work, seasonal reminders, priority scheduling and service discounts. If your furnace hasn’t been serviced yet, fall is a great time to schedule a visit before colder temps creep in.

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