# How do you size a fan motor?

Contents

The key indicator for determining fan motor size is fan brake horsepower (BHP), which represents the force needed to brake, or stop, the motor. This is the minimum amount of power needed to operate the fan. Your fan manufacturer will always specify brake horsepower.

## How do I know what size fan motor I need?

Using the specifications of the fan blade is the best way to determine the correct horsepower for a replacement condenser fan motor. The diameter, angle and number of fan blades, along with the RPM of the motor, are the pieces of information necessary to make this determination.

## How is fan horsepower calculated?

Step-1 Formulas:

1. When total static pressure and overall efficiency are defined, fan input power is: Pf = Vf ΔPs K1 / (ηo)
2. When motor brake horsepower is defined, input power is: Pf = BHP * K2 / ( ηe )
3. Brake Horsepower: BHP = ( ηe * Pf ) / K2.
4. Fan input power at part-load: Pf,pl = [(Pf,fl) (Rpl)] / 100.
INTERESTING:  How do you fill a c4 transmission?

## Does HP matter on condenser fan motor?

Although it is not too difficult to change a condenser fan motor, it is still possible to do it incorrectly. Of course you need a motor that operates at the same voltage, phase, and frequency of the original motor and it should also be the same horsepower.

## What is the difference between a fan motor and a blower motor?

Unlike the condenser fan motor, the blower motor is located indoors. It’s the component that blows cool air through the ducts and into different parts of your home. So it’s essentially your air mover. … A properly functioning blower motor delivers stronger airflow to improve air circulation in your home.

## Is a 3 or 4 blade fan better?

4-blade ceiling fans are less noisy and are useful in rooms with an air conditioner, to move the cool air around. They are often more stylish looking. However, 4 blade fans may move air slower than a 3 blade fan and can be more expensive than 3 blade ceiling fans.

## What is a good cfm for a fan?

On high speed: Good CFM ranges from 4,000 to 5,000. Better ranges from 5,000 to 6,000. Best is over 6,000.

## How do I choose a fan motor?

The key indicator for determining fan motor size is fan brake horsepower (BHP), which represents the force needed to brake, or stop, the motor. This is the minimum amount of power needed to operate the fan. Your fan manufacturer will always specify brake horsepower.

## What is the difference between BHP and HP?

HP is the output horsepower rating of an engine, while BHP is the input brake horsepower of an engine. … B HP is the measurement of an engine’s power without any power losses, while HP is BHP less the power losses. 3.

INTERESTING:  Best answer: Who discovered the motor effect?

## How do you convert CFM to HP?

CFM can be converted into HP by multiplying the airflow by 1.6 and then multiplying that result by 0.9.

## How much does a fan motor cost?

The average cost of a condenser fan motor is between \$300 and \$500 (not including installation). If the compressor breaks, you are looking at a much costlier problem which could cost up to \$2000. In some cases, your fan motor may be under warranty.

## What is the most common type of single phase motor is used in HVAC?

PSC motors are much more efficient than shaded pole. the most common type of single phase induction motor. Equipped with a starting winding displaced in magnetic positon from, and connected in parallel with the main winding.

## What are the two motors on a furnace?

There are two different types of blower motors for your forced air system, the PSC (permanent split capacitor) and ECM (electronically commutated motor). PSC motors were the old standard, and if your furnace is over 5 years old it probably has one.

## Which is better cooling fan or blower?

Airflow: … But blowers create high pressure airflow from the cooling system with higher speed and air throw. Hence fan type coolers are ideal for entire room cooling whereas blower types are good for instant cooling in a specific area.

## What is a PSC fan motor?

A PSC (permanent split capacitor) is a type of motor used that turns on and off. It’s commonly used on fans, blowers, small pumps and gear motors. Chances are, your existing HVAC equipment has a PSC motor. With a PSC motor, the electrical output is not controllable and has no intermediate speeds.

INTERESTING:  Frequent question: Can a car seat fit in a Mustang?