What Size Wall Furnace Do I Need?
Wall Furnace Sizing Calculator
Adding a wall furnace to your room can open up a world of comfort during the cold winter months. However, if your wall furnace isn't sized properly, you could wind up paying more while remaining uncomfortable.
Use the following wall furnace sizing calculator to help you pick the right wall furnace size:
Step 1. Basic Info
Step 2. Room Info
Step 3. Construction
Step 4. Results
Total Load Calculations
Cooling Load:
Heating Load:
Basic Room & Home Information
Room Size:
Zip Code:
Room Type:
Building Age:
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* For more accurate load calculations, you can edit the detailed information below.
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Tell Us About Your Home
Fill out all of the fields provided to calculate your heating and cooling loads. We'll use that information to help you find the right mini split system for your home.
Select the approximate age range of your home. We will use this to make an estimate of the quality of insulation of your home.
Because different types of rooms are used differently, they have different heating and cooling needs.
Calculate Load Estimates
Temperature Information
High: 90°F | Low: 10°F
Outdoor Design Temp. determined by ZIP Code.
Next: To Wall Details
Wall Details
Select 'Yes' if this wall separates the space being conditioned from the outdoors or an unconditioned space like a garage. Otherwise, if this wall is adjacent to another conditioned space, select 'No'.
Enter the width of the wall. If only a portion of the wall is "Exposed", enter this width.
Select 'Yes' if this wall separates the space being conditioned from the outdoors or an unconditioned space like a garage. Otherwise, if this wall is adjacent to another conditioned space, select 'No'.
Enter the width of the wall. If only a portion of the wall is "Exposed", enter this width.
Select 'Yes' if this wall separates the space being conditioned from the outdoors or an unconditioned space like a garage. Otherwise, if this wall is adjacent to another conditioned space, select 'No'.
Enter the width of the wall. If only a portion of the wall is "Exposed", enter this width.
Select 'Yes' if this wall separates the space being conditioned from the outdoors or an unconditioned space like a garage. Otherwise, if this wall is adjacent to another conditioned space, select 'No'.
Enter the width of the wall. If only a portion of the wall is "Exposed", enter this width.
Window Details
North
We assume Windows are 3'x4'. If your windows are larger or smaller, please adjust accordingly.
We assume French Doors are 3'x7'. Each half of a double door should be counted separately.
We assume Sliding Doors are 6'x7'. If your doors are larger or smaller, please adjust accordingly.
East
We assume Windows are 3'x4'. If your windows are larger or smaller, please adjust accordingly.
We assume French Doors are 3'x7'. Each half of a double door should be counted separately.
We assume Sliding Doors are 6'x7'. If your doors are larger or smaller, please adjust accordingly.
South
We assume Windows are 3'x4'. If your windows are larger or smaller, please adjust accordingly.
We assume French Doors are 3'x7'. Each half of a double door should be counted separately.
We assume Sliding Doors are 6'x7'. If your doors are larger or smaller, please adjust accordingly.
West
We assume Windows are 3'x4'. If your windows are larger or smaller, please adjust accordingly.
We assume French Doors are 3'x7'. Each half of a double door should be counted separately.
We assume Sliding Doors are 6'x7'. If your doors are larger or smaller, please adjust accordingly.
Garage Door Details
Each single garage door should be counted as 1 and each double garage door should be counted as 2.
Next: To Ceiling Details
Ceiling Details
Select 'Yes' if the ceiling separates your space from the outdoors, an attic, or any other unconditioned space. Otherwise, if there is another conditioned room above your space, select 'No'.
Enter the height of your ceiling. If you have a sloped, vaulted, or any other type of non-flat ceiling, enter the approximate average ceiling height.
Next: To Floor Details
Floor Details
Select 'Yes' if the floor separates your space from the outdoors, an unconditioned crawlspace or basment, or is a slab on grade. Otherwise, if your space is over a conditioned room, select 'No'.
Continue to Construction
Wall & Window Details
Garage Door Details
Ceiling Details
Floor Details
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Submit & View Results
Basic Room & Home
Room Type
Room Size
ZIP Code
Building Age
Temperature
Edit
Avg. Outdoor Temp. High
°F
Avg. Outdoor Temp. Low
°F
Desired Indoor Cooling
°F
Desired Indoor Heating
°F
Walls
Edit
Wall Type
Wall Insulation Quality
North Wall Exposed Area
East Wall Exposed Area
South Wall Exposed Area
West Wall Exposed Area
Garage Door
Edit
# of Garage Doors
Garage Door Insulation Quality
Windows
Edit
Window Type
North Wall
East Wall
South Wall
West Wall
Ceiling
Edit
Ceiling Exposed
Ceiling Insulation Quality
Ceiling Type
Floor
Edit
Floor Exposed
Floor Insulation Quality
Floor Type
Load Results (BTU/hr)
Cooling load
Wall
Window
Ceiling
Floor
Bay
Infiltration
Internal
MRA ?
Moisture Removal Allowance: It is typical for roughly 30% of your air conditioner's capacity to be used to reduce the humidity in your home.
Total
Heating load
Wall
Window
Ceiling
Floor
Bay
Infiltration
Total
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Disclaimer: This sizing tool, although based on a version of the ACCA Manual J, is for informational use and is intended only as a guide to assist with finding the best product for your needs. Since the calculations are based on the information provided, Power Equipment Direct, Inc. assumes no responsibility for inaccuracies resulting from improperly sized equipment. For a complete, professional sizing estimate, please call us at 866-554-HEAT (4328).
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So How Do I Find the Right Size Wall Furnace For My Space?
A common, misguided way of choosing a wall furnace is to use simple, rule-of-thumb sizing methods like estimating based off square footage.
Unfortunately, there are many other factors that can raise or lower your BTU requirements dramatically, such as your climate, building structure, and more.
Outside of getting a complete sizing estimate of your space, your best bet is using our online wall furnace sizing calculator. Our proprietary software will lead you through some brief, yet specific, questions about your space and provide the best sizing.
Why is Sizing Important?
If your wall furnace is too small, it will run constantly while trying to meet the demand, but never get the room to the temperature you want. The furnace will also suffer from overuse and experience premature damage.
On the other hand, if the wall furnace is too large, you'll probably experience large temperature swings throughout the day, as well as lower-than-expected energy efficiency due to frequent cycling of the unit. This frequent starting and stopping could damage your system over time.
Also, don't forget about the extra upfront cost of buying a larger wall furnace than you need!
NEXT: Shop For Your Wall Furnace
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