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Can You Run A Furnace Without A Filter Temporarily?

You can run a furnace without a filter for an hour or so. But running it for more than that can cause health hazards and poor air quality. If your system has an evaporator coil, it cannot function without a filter. The primary purpose of a furnace filter is to protect your HVAC equipment. Without one, the evaporator coil will act as the filter, causing further problems.

When various HVAC components get caked in dust, they run less efficiently and cause your system to overheat and short cycle. Moreover, if anyone in your household has allergic sensitivities, not having a filter might not be the best decision.

Maintenance of your furnace filter and replacing it every 1-3 months can help prevent a system failure. Here are a few consequences you might face running a furnace without a filter for an extended period:

Poor Air Quality

A filter prevents dust and debris from being sucked into your furnace. Not having one ultimately leads to inferior air quality in your home, which might exasperate any breathing issues like asthma and allergies. Your air purifiers will have to work harder to filter out allergens in the air.

The absence of a filter can significantly reduce air flow over time. Most customers complain that there is not much airflow due to dust caked in air ducts and vent covers.

• Polluted Ductwork

Not having a filter will result in air pollutants settling in the ductwork. Continuously running your furnace without a filter allows mould growth in your system. Moisture promotes mould growth in your ductwork, contributing to an overall decline in air quality and more severe health hazards for those with mould allergies.

System Failure

Besides air quality and health, the primary function of a filter is to protect the furnace. Without a filter to provide that protection, your system can get coated in grime, while the evaporator coils or the blower motor could fail due to the added stress.

Without a filter, your furnace will have reduced efficiency, requiring more work and energy to reach the target temperature. Even a slight dust coating on the evaporator coil can affect its performance- reducing its efficiency by 50% or more.

If you cannot find the correct filter size, opt for an oversized filter (or even two) and cut it to fit. Use duct tape to keep it together in the filter slot- it is better than nothing. You can find standard-sized filters at your local grocery stores. A furnace can function without a filter, but it does so at a cost. You may run it for a short period without problems, but it is better to invest in one.

For Furnace repair and maintenance in Vaughan, ON and surrounding areas, get in touch with Martino. Our team of well-trained mechanics are here to cater to your needs and resolve your issues. You can also book an appointment with our team of professionals to have your system checked.