Heat, energy & performance
Humidity is the hidden half of a hot kitchen. Steam from boiling, blanching and washing makes the room feel far hotter than the thermometer reads and stops the body shedding heat. The extract is what clears that moisture at source - when it is clean and pulling its airflow, the mugginess lifts.
The short answer
Humidity is the hidden half of a hot kitchen. Steam from boiling, blanching and washing makes the room feel far hotter than the thermometer reads and stops the body shedding heat. The extract is what clears that moisture at source - when it is clean and pulling its airflow, the mugginess lifts.
The detail
A kitchen generates a lot of water vapour - every pot of boiling stock, every pass through the wash-up, every blanch. That steam rises with the heat plume, and the canopy is meant to catch it and take it outside before it fills the room. Humidity is one of HSE's six thermal comfort factors for good reason.
When the air is humid, sweat evaporates poorly, so the body cannot cool itself. That is why a muggy kitchen at 26 degrees feels worse than a dry room at the same temperature. Reducing humidity is often the fastest way to make a hot kitchen feel bearable, and extraction is the main route to do it.
A greased extract loses the airflow to clear that moisture. As capture velocity falls, steam that should have left through the duct lingers and spreads, and the room turns damp as well as hot. The same grease that traps heat traps humidity, and the two together make the space feel far hotter than the numbers suggest.
Moisture also undermines odour control. Activated carbon, used to scrub cooking smells, preferentially adsorbs water over some odour molecules, so a humid exhaust reaches the carbon already loaded with moisture and scrubs odour less well. A steamy system is a smellier one too, which is why airflow and humidity are worth fixing together.
What it means for you
If the kitchen feels clammy rather than simply warm, humidity is the issue, and the extract is the control. Portable fans move damp air around without removing the moisture; only extraction actually takes the vapour out of the building. Restoring its airflow is what lifts the mugginess.
Balanced make-up air matters here too. Supply air at around 85 percent of the extract rate replaces what is drawn out with drier tempered air, rather than leaving the room to pull in humid air through gaps. Extract and supply working together keep the moisture moving in one direction - out.
Phoenix Duct Clean restores the extract airflow that clears steam at source, so the room feels cooler and drier, and the downstream odour control works as intended.
The service behind the guide
Sibling guides
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Questions
Humid air stops sweat evaporating, so the body cannot cool itself. A muggy kitchen feels far worse than a dry room at the same temperature. HSE lists humidity as one of six thermal comfort factors for this reason.
The canopy captures steam with the heat plume and takes it out of the building. A clean extract pulling its design airflow clears that moisture at source; a greased one loses the airflow, so steam lingers and the room turns damp.
Only a little. Fans move damp air around but do not remove the moisture. Only extraction actually carries the water vapour out of the building, so restoring extract airflow is what genuinely reduces the humidity.
Yes. Activated carbon used for odour control preferentially adsorbs water over some odour molecules, so a humid exhaust scrubs smells less effectively. A steamy system tends to be a smellier one, so the two are worth fixing together.
Yes. Balanced supply air at around 85 percent of the extract rate replaces extracted air with drier tempered air, rather than the room pulling humid air in through gaps. Extract and supply together move moisture out.
Phoenix Duct Clean · by the numbers
Humidity is an airflow problem. Book a TR19 clean to clear the steam at source.