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What to do when your heater or furnace won't turn on.

What to do when your home’s heater or furnace isn’t turning on. 

If you have a modern HVAC system, you may also be getting an error message on your thermostat that won’t allow you to use your heater.  Here’s what to do!

What To Do When Your Heater Isn’t Turning On
The chilly season brings about the need for a warm, cozy home. Yet, sometimes homeowners face the frustrating dilemma of a heater that refuses to turn on. The room remains cold, the walls seem to seep in frost, and the supposed warmth provider, your heater, is not doing its job. So, what exactly should you do?

Modern Heaters and Thermostat Error Messages:
Firstly, it’s essential to acknowledge that modern heating systems have come a long way in terms of technology. Today, when they encounter problems, they might not just silently malfunction. Instead, they might present an error message on your heater’s thermostat, effectively locking out the system’s operation. Such a feature can be beneficial because it signals that there’s an issue, but it also means that troubleshooting has become a tad more sophisticated.

Potential Causes for a Heater Breakdown:
Various factors can cause your heating system to stop working. Some of the primary reasons include:

Electrical Issues: Wiring problems or blown fuses can prevent your heater from starting.
Mechanical Wear and Tear: Over time, parts of your heating system might wear out, leading to malfunction.
Ignition Problems: For heaters that rely on ignition, a faulty igniter can be the culprit.
Thermostat Malfunctions: Sometimes, the issue might not be with the heater itself but with the thermostat that controls it.
Blocked or Dirty Filters: A blocked filter can restrict airflow, causing the heater to overheat and automatically shut off for safety.
Fuel Supply Issues: For heaters that rely on fuel (like gas or oil), a disruption in the supply can halt its operation.
Homeowner’s Checklist: When Your Heater Won’t Turn On:
Before panicking, here’s a list of things homeowners can check:

Thermostat Settings: Begin with the most basic – ensure your thermostat is set to “heat” and the desired temperature is higher than the room temperature.
Power Source: Check if the heater is plugged in and the circuit breaker hasn’t tripped.
Fuel Supply: For gas heaters, a.k.a., a furnace, make sure that your main gas valve is turned on. Believe it or not, we’ve revieved calls for heaters not turning on and the gas was turned off…
Air Filters: Inspect filters for blockages or excessive dirt and clean or replace them if necessary.
External Switches: Some heaters have external switches that might have been accidentally turned off.
Error Messages: If your thermostat displays an error, noting down the code can help in troubleshooting or communicating the issue to a professional.

Dangers of a Malfunctioning Gas Furnace:
Gas furnaces, while effective, come with their set of risks, especially when malfunctioning:

Carbon Monoxide Poisoning: A faulty gas furnace can leak carbon monoxide, a colorless and odorless gas that can be deadly.
Explosions: Gas leaks, if ignited, can lead to devastating explosions.
Fire Hazards: A malfunctioning furnace can pose fire risks, especially if there are flammable materials nearby.
Respiratory Problems: Leaks can lead to respiratory issues, especially in people with pre-existing respiratory conditions.
For these reasons, it’s crucial to have functioning carbon monoxide detectors in homes with gas furnaces and to take any unusual smells or sounds seriously.

A malfunctioning heater, especially during the cold season, can be more than just an inconvenience. It’s essential to act promptly, understand the potential risks, and when necessary, seek professional help. Being proactive not only ensures comfort but also the safety of your home and loved ones.

Seeking Professional Help:
While the above steps can serve as initial troubleshooting, it’s vital to recognize when a problem is beyond a layperson’s skills. If you’re in San Antonio, Texas, and your heater shows signs of trouble, remember that expert help is just a call away. Air & Plumbing Today is committed to ensuring that residents have warm and safe homes. By dialing 210-519-5959, homeowners can book a free estimate and have their heating systems inspected and repaired by professionals.




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