Electrical Room Ventilation Calculator
Exhaust airflow to remove heat from an electrical/switchgear room.
Enter your values
ⓘ Live results
Results
- Required exhaust airflow
- 3,159 CFM
- Heat load
- 51,180 BTU/hr
- Fan control
- Thermostatically controlled exhaust fan recommended
- Note
- Verify against equipment manufacturer's specific heat rejection data
Quick answer
Electrical and switchgear rooms are ventilated to remove equipment heat gain, typically sized from the heat dissipated by transformers and switchgear divided by the allowable temperature rise.
CFM = heat (BTU/hr) / (1.08 x allowable temp rise)
How to use the Electrical Room Ventilation Calculator
- 1Estimate total equipment heat dissipation in kW (from nameplate losses or manufacturer data).
- 2Choose an allowable room temperature rise, often 10-15°F above outdoor/intake air.
- 3Use a thermostatically controlled fan so airflow tracks actual heat load.
Worked example
Using the values the calculator loads with:
Inputs
- Equipment heat dissipation15 kW
- Allowable temperature rise15 °F
Results
- Required exhaust airflow3,159 CFM
- Heat load51,180 BTU/hr
- Fan controlThermostatically controlled exhaust fan recommended
- NoteVerify against equipment manufacturer's specific heat rejection data
Frequently asked questions
Why not just use AC instead of ventilation?
Simple exhaust ventilation is far cheaper where outdoor air is cool enough; AC is reserved for rooms needing tighter temperature control.
Does dust matter for switchgear rooms?
Yes — filter intake air to keep conductive dust off busbars and breakers.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.