How to Shut Off Your Furnace

Temporary Steps When Your Furnace is Blowing Cold Air

Ensuring the reliability of your heating system as the seasons change is vital for comfort and efficiency. When a furnace, which serves as a primary heat source in many Calgary homes, starts to distribute cold air, it is a sign of a furnace problem that demands immediate attention.

This can disrupt your home’s warmth and mean your furnace is bringing in cold air from outside because of a problem. To prevent potential damage and conserve energy, shutting off your furnace until it can be repaired is the recommended course of action. Below is a guide to safely turn off your furnace, an essential aspect of furnace maintenance.

Step 1: Understanding the Issue

A furnace that’s emitting cold air can stem from a variety of issues, including a faulty heat exchanger or a simple thermostat mishap. If you’re experiencing this issue, first ensure that your thermostat is set to ‘Heat’ mode and the temperature is higher than the current ambient temperature. If cold air persists, it’s a good idea to proceed with shutting off your furnace.

Step 2: Locating the Power Source

All HVAC systems, regardless of whether they are a gas furnace or electric, require electrical power to operate the fans and controls. Identifying the source of electricity to your furnace is the first step towards shutting it down.

Step 3: Following the BX Cable

To find the power switch, trace the BX cable from the furnace itself. This metal armored cable is designed to withstand the demands of furnace installation and operation, leading you directly to the dedicated power switch.

Step 4: Shutting Off the Furnace

Flip the power switch, usually found on a wall near the furnace, to the ‘Off’ position to discontinue the operation of your heating system. This simple action is a fundamental part of furnace maintenance and can prevent further complications.

Step 5: Confirming the Shutdown

A proper shutdown will be indicated by your thermostat’s response; it should cease signaling the furnace to activate. This confirmation is an important step in ensuring that your HVAC system is indeed no longer operational.

Step 6: Scheduling Professional Service

Once your furnace is securely off, it is critical to not leave the issue unaddressed. AAA Heating and Plumbing offer comprehensive Calgary furnace maintenance services, including 24/7 emergency repair service. Our experienced technicians are adept at diagnosing and solving any furnace problem, ensuring your heating system operates efficiently and safely.

Contact Us Today

If your furnace is simply blowing cold air, turning it off is a good interim solution. This action conserves energy and prevents additional damage until professional help can be obtained. AAA Heating and Plumbing specialize in emergency furnace repair and maintenance, including emergency services to resolve issues swiftly. For any heating system needs—from furnace maintenance to a new furnace installation—trust in our team to provide reliable, professional service at any hour.


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