Table of Contents
How many CFM do I need to cool a BTU?
Now if you want to reduce theoretical concepts down to rules of thumb, the standard volume flow rate per unit of power in the HVAC industry is 400 cfm per ton, and a ton is 12,000 BTU’s per hour, so 400 cfm per 12,000 BTU’s per hour of cooling capacity.
How do you calculate BTU from CFM?
Sensible heating Btu is measured by the ageless formula CFM x Delta-T x 1.08. To measure heating Btu, multiply the measure supply airflow (in cfm) by the temperature change from the average supply register temperature to the average return grille temperature, and multiply this total by the formula constant of 1.08.
How many CFM do I need?
The rule of thumb is that you need at least 1 CFM per square foot of room area. To determine the square footage of your bathroom, multiply the length times the width. For example, if your bathroom is 6 feet wide and 9 feet long, its square footage is 54. Therefore, it should have a fan rated for at least 54 CFM.
How do you calculate air flow in exhaust fan?
You measure the velocity at a points in the duct and find the average velocity in the exhaust duct is 400 FPM. Multiply 400 Feet per Minute times the area of the duct, which is . 35 square feet, to find 140 CFM exhaust fan airflow. Each fan manufacturer publishes fan performance tables for each fan.
How many CFM is a 90000 BTU furnace?
90,000 BTU Furnace, 80\% Efficiency, Single-Stage Burner, 1,600 CFM High-Efficiency Blower, Upflow/Horizontal Flow Application.
How many BTUs do I need?
Size and Ceiling Height
| Area To Be Cooled (square feet) | Capacity Needed (BTUs per hour) |
|---|---|
| 100 to 150 | 5,000 |
| 150 to 250 | 6,000 |
| 250 to 300 | 7,000 |
| 300 to 350 | 8,000 |
What is a good fan CFM?
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 an exhaust fan for my kitchen?
- The size of the exhaust fan is the main criterion for selecting an exhaust fan for the bathroom (or kitchen). The airflow or amount of air exchanged per minute by the exhaust fan is measured in CFM (cubic feet per minute).
- The preferred location of the exhaust fan is near the shower area or the bathtub of the bathroom.
What is a good cfm for a fan?
How many CFM is a 80 000 BTU furnace?
1600 CFM
80,000 BTU 96\% AFUE Variable Speed Goodman Gas Furnace 1600 CFM – Upflow/Horizontal.
How much CFM do I need for a range hood fan?
The size, shape, length, turns, and cap on the range hood ductwork adds resistance which reduces the amount of air the vent fan can move, requiring additional CFM for the fan. When using smooth, round 8” diameter, metal pipe, add one CFM per foot of pipe, plus 25 CFM for each elbow, and 40 CFM for a roof cap.
How much CFM do I need for my Kitchen?
Here’s how to calculate exactly how much CFM you need based on the size of your kitchen. First, determine the volume of your kitchen. To calculate your kitchen’s size in cubic feet, multiply the length by the width and height. For example, your kitchen is 18’ long x 14’ wide x 9’ tall = 2,268 cubic feet.
What size airflow do I need for my Ceiling Fan?
Answer: You need an 80 CFM airflow (for 300 sq ft standard room and 2 ACH). Here’s a neat CFM calculator that calculates CFM based on room area, ceiling height, and the number of air changes per hour (ACH).
How do you calculate the CFM of a 120 watt fan?
First, convert watts to Btu/hr, then solve for the CFM requirement for the equipment fan (s). 1 W = 3.415 Btu/hr, so 120 W = approximately 410 btu/hr, which is the amount of cooling needed to offset that heat. And the equation for determining the CFM is: