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Heat Load / BTU

Convert IT equipment draw, people and lighting into a heat load (BTU/h, kW and tons of refrigeration) and get the recommended air-conditioning capacity, with a safety factor. Simplified model: excludes wall and solar gains. 100% in your browser.

Sum of the actual power of switches, servers, NVRs, etc. (watts).

People regularly present. Each one adds ~100 W (≈341 BTU/h).

Total power of the room's light fixtures. Leave at 0 if not applicable.

Margin for growth, peaks and losses. Typical 20–30 %.

Examples
redzilla.cl — btu 
 
  
 
 
Total heat load
 
—
 
—
 
 
 
In kilowatts
 
—
 
—
 
 
 
Recommended A/C
 
—
 
cooling capacity
 
 
  
 
 BTU/h —  
 
 kW —  
 
 Ton —  
 
  
 
Calculation breakdown
 
 
  
Heat sourceBTU/hNote
   
 
 
 
 How it's calculated · BTU, kW and tons 
 
 1. Base conversion: 1 W = 3.412 BTU/h.
            All the power the equipment draws is dissipated as heat in the room.

 
 2. equipment BTU = W × 3.412 ·
people BTU = people × 100 × 3.412 (≈341 BTU/h each) ·
lighting BTU = W_light × 3.412.

 
 3. Total BTU/h = (sum) × (1 + safety/100).
            The safety factor covers growth and peaks.

 
 4. kW = BTU/h ÷ 3412 ·
tons of refrigeration = BTU/h ÷ 12000.

 
 5. Simplified model: it does NOT include gains through walls, ceiling,
            windows, sunlight or air infiltration. For a room with solar exposure or external walls,
            commission a full heat-load calculation from an HVAC specialist.

 
 
 
 
 
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