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Furnace Repair: Why Your Heat Won’t Turn On

Heater problems can be very aggravating, especially when they occur during freezing weather. There are few things more frustrating than waking up to a cold home. Having a reliable company you can turn to for emergency furnace repair is essential to restoring heat quickly and keeping the home safe. There could be several things wrong with the furnace. A skilled technician will be able to correctly diagnose the issues the first time. This not only restores heat faster but also helps avoid additional damage.

Lancaster Plumbing, Heating, Cooling, and Electrical cares about your comfort. This guide walks you through the many things that can cause a furnace to not turn on. It also explains what to do in each scenario.

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What To Do When Your Heat Won’t Turn On

When you first notice your heater not producing heat, you need to act as fast as possible. Most homes with good insulation can stay warm for 8 to 12 hours without additional heat. After that period, the indoor temperature will drop dramatically. If the furnace issue occurs during freezing weather, the drop may be quicker.

A cold home doesn’t just impact your comfort. It can affect the plumbing too by increasing the risk of frozen and burst pipes. This is another reason to act as quickly as possible to restore the heat.

There are a few simple checks you can perform yourself to try to get the heater to turn back on and produce heat. If the tips below don’t work, you’ll need to call us here at Lancaster Plumbing, Heating, Cooling, and Electrical.

Check for Thermostat Issues

Thermostat malfunctions and incorrect settings are some of the leading causes of a furnace that won’t turn on. You may have accidentally left the thermostat on Cool mode, which will definitely cause heating issues. Switching it to Heat may resolve the heating error.

The batteries in the thermostat could also be dead, which will prevent heat during power outages. If this is the case, the thermostat’s screen will be blank. Replacing the batteries should fix the heat issue, provided the furnace has backup power connected.

There’s also a possibility that you have the temperature set too low. This will prevent the furnace from kicking on because it believes the home is already warm enough. Increasing the temperature may trigger the furnace to turn on.

If you use programmed scheduling on the thermostat for heat, take another look at it. There’s a chance you changed the schedule without realizing it. Simply resetting the programmed schedule may restore normal heating operation.

Furthermore, the thermostat may have dirty sensors or incorrect wiring, both of which can result in no heat. If you suspect a dirty sensor, feel free to wipe it off. However, if you think the thermostat has wiring issues, you should let a professional handle the repair. You don’t want to risk damaging the thermostat or electrocuting yourself.

Look for a Tripped Breaker

Furnaces, both gas and electric, need a secure connection to the home’s electrical system to operate reliably. During a power outage, these heaters won’t turn on unless backup power is in place. They also won’t turn on if the circuit breaker they’re connected to trips. Checking your electrical panel for a tripped breaker is an easy way to see if this is the culprit. Flipping the tripped switch back to the ON position may reset the connection and turn the furnace back on.

Most circuit breakers last anywhere from 20 to 40 years before they need replacement. If you think the breaker is ready for an upgrade, this is another job for a trained electrician.

Check Furnace Switch

Most furnaces come with a switch that looks like a standard light switch; this is the power switch for the heater. You can usually find the switch on the side of the furnace itself or on a nearby wall. If it’s in the wrong position, the furnace won’t turn on. Switching it back to the On position should fix your no-heat problem. Give it a few minutes to cycle on, as it can take a while to start up.

Change Furnace Filter

Just like your air conditioner, your furnace has an air filter. And once the filter becomes clogged, it can prevent the unit from producing conditioned air. The filter’s dirtiness prevents air from flowing through, making it nearly impossible to heat the home. Replacing it with a clean one will likely fix the heat issue.

How often you need to change the filter greatly depends on the system’s usage. In Pennsylvania, the winters are long and cold. Changing the filter once every 30 days should be enough to keep the furnace running smoothly. If you have pets, though, you may need more frequent filter replacements due to pet hair and dander.

Check Gas Supply

Gas furnaces must have a secure gas connection at all times to operate effectively. If the handle to the gas valve is not running parallel to the gas pipe, this means it’s in the closed position. Someone may have accidentally left it closed after doing maintenance or repairs. Adjusting the handle to the open position may restore the furnace’s normal operation.

Propane furnaces depend on a connected tank with propane to function correctly. If you check the exterior tank and it’s empty, that’s your problem. You’ll need to call the local propane company to have the tank refilled. The same applies to furnaces that run on heating oil: an empty oil tank means no heat. Getting the tank refilled should restore the heater’s ability to heat.

When Is No Heat an Emergency?

Just because it isn’t freezing-cold outside doesn’t mean you don’t need to act fast when your furnace won’t produce heat. You don’t want to risk your home becoming too cold. You also don’t want to risk carbon monoxide exposure, which could be life-threatening if the problem stems from a gas leak.

These are the types of furnace problems that need emergency service:

  • No heat during freezing weather
  • Gas smell near furnace
  • Carbon monoxide alarm sounding
  • Furnace repeatedly shutting off
  • Loud banging or popping noises
  • Electrical burning smell present
  • Furnace not turning on at all
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Call Lancaster Plumbing, Heating, Cooling, and Electrical today to schedule a furnace repair in Lancaster.

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Why Choose Lancaster Plumbing, Heating, Cooling & Electrical

Serving Lancaster County with Top-Rated Home Solutions Since 1904

When you need a reliable partner for all your home services in the Lancaster area, trust Lancaster Plumbing, Heating, Cooling & Electrical. From our location in East Petersburg, we can provide fast, professional HVAC, plumbing, and electrical services anywhere in Lancaster County and the surrounding communities. We have some of the best technicians in the business. Our company features:

  • Industry-leading quality assurance
  • Trained, experienced personnel
  • Background-checked, drug-tested technicians
  • Convenient scheduling
  • A 100% satisfaction guarantee
  • An A+ rating from the BBB

When you need the ultimate in-home comfort, choose Lancaster Plumbing, Heating, Cooling & Electrical. Call us today at (717) 207-8198 or contact us online to schedule service in Lancaster or South Central Pennsylvania.