If you're asking, “Can I put a bigger blower motor in my furnace?” the correct answer is no. Furnace manufacturers carefully assemble the components that make up the system after rigorous testing. Installing a bigger blower motor can upset the balance, leading to various issues.
If you have a direct drive blower where the motor lies within the blower wheel then you cannot install a physically larger motor but can install a greater hp rated one. You have to make sure that the mount can take the extra weight. A larger motor may not give you more airflow though.
Irregular Temperatures. You'd expect an oversized furnace to produce an excellent heat output. However, when a furnace is too big for a building, it will struggle to maintain the thermostat's settings. Its inefficiency and short cycling will cause the unit to heat the property unevenly.
When increasing the blower speed, loosen the setscrew a little bit. This is the part that holds the pulley to the furnace's driveshaft. Turn the pulley one rotation clockwise on the shaft. If you want even more speed, do two rotations.
Only thing that matters is voltage, RPM, HP and if the motor fits. The motor being an inch short or longer doesn't matter as long as it spins.
Are Furnace Blower Motors Universal? Yes and no. There are universal motor replacements for electric and gas-powered furnaces. However, which one you buy will also depend on your existing motor's horsepower, voltage and rotations/revolutions-per-minute (rpm).
Steps to Change Furnace Blower Speed
Turn off any gas lines. When it's safe, open the main furnace panel. The blower motor sits near the base and next to the main air filter. For a pulley blower motor, adjust the length of the pulley to increase or decrease the speed.
Upgrading your HVAC blower motor can significantly improve the performance and efficiency of your heating and cooling system. Whether you're experiencing issues with your current motor or simply looking to enhance your home's comfort, an upgraded blower motor can offer numerous benefits.
Check Your Vents & Ducts.
Make sure your vents are open and unobstructed. Sometimes belongings or furniture can inadvertently cover them, blocking airflow and preventing heat from reaching the room. Also, do not close vents in unused rooms as this can cause airflow issues as well.
Neither oversizing nor undersizing your AC unit is ideal. Both scenarios can lead to issues with efficiency, comfort, and longevity of the system.
1,200-square-foot home will require between 35,000 and 75,000 BTUs. 1,800-square-foot home will require between 45,000 to 90,000 BTUs.
The more BTUs a furnace has, the larger the area it can heat. However, bigger isn't always better. If your furnace has insufficient BTUs, it'll work non-stop and never keep your home at a comfortable temperature. Alternatively, a furnace with too many BTUs will frequently cycle and be inefficient.
This can be caused by a loose fan belt, or a dirty motor. Solution: First, clean the blower fan and the area around it. It has to deal with a lot of air, so it naturally becomes dirty over time. If that doesn't fix it, the fan belt probably needs to be replaced.
Furnace Blower Options
In essence, the unit is either operating at full capacity when the thermostat calls for heating, or it is turned off when the demand is met. Single speed blowers are factory calibrated to operate between 1200-1800 CFM, which will generally meet the requirements of a 1000-2000 square foot home.
Common issues like leaks, disconnections, or obstructions within the ducts disrupt the flow of cooled air, causing rooms farther from the HVAC unit to suffer the most. In some cases, inadequate insulation of ducts can allow heat to infiltrate, further exacerbating the problem.
From dirty air ducts, blocked damper valves, damaged duct runs, to an insufficient numbers of return air vents, there are a variety of signs that may indicate a furnace air flow issue in your home.
No, you should not put a bigger blower motor in your furnace.
Furnace: A blower motor in a furnace can last a minimum of 10 years but up to 20 if you schedule regular maintenance to keep your unit in good condition. Heat Pump: Like a furnace, a blower motor in a heat pump can last at least 10 years, and up to 15 if the unit undergoes regular maintenance.
Adjusting the Blower Speed
You can increase or decrease the blower speed by slightly adjusting the pulley on the blower drive motor. To increase blower speed, slightly loosen the setscrew that holds the pulley to the driveshaft. Move or turn the pulley clockwise on the shaft one turn, then tighten setscrew.
If you feel like your furnace is struggling to heat your home, especially in rooms located far from the unit, there's an inexpensive way to give it a boost of extra power. Installing a booster fan in your HVAC system ductwork will increase airflow to rooms that are struggling to get warm air.
Running your furnace fan continuously in winter has its pros and cons. It can improve air circulation and quality but may also lead to higher energy bills and increased wear on your system.
High CFM: If you need to clear large areas with a lot of leaves and debris, a leaf blower with a high CFM is more efficient. It will move more at once, saving you time and effort. High MPH: A high MPH leaf blower is your best bet if you're dealing with wet leaves or stubborn debris.