Commercial Kitchen Exhaust Air-to-Air Heat Recovery

Commercial Kitchen Exhaust Air-to-Air Heat Recovery

A commercial kitchen exhausts air at 40–60°C, heavy with grease and moisture — and code requires that exhaust to be balanced by an equal volume of make-up air. Conditioning all that make-up air from scratch is a huge energy load. An air-to-air heat exchanger placed between the exhaust and the make-up air stream pre-conditions the incoming air for free, cutting heating (and in summer, cooling) cost dramatically.

Why Kitchens Need Heat Recovery

During a winter service, a 10,000 m³/h exhaust at 45°C against −5°C outdoor means roughly 10,000 × 1.2 × 50 / 3600 ≈ 167 kW of thermal energy leaving the building every hour. Recovering even 60% of that through a sensible core returns ~100 kW to the make-up air — often the difference between a viable energy bill and an impossible one. See our application library for more duty examples.

Plate Core vs Rotary Wheel in a Kitchen

Grease decides the core. A fixed plate exchanger has smooth, accessible channels that can be washed or have removable grease filters upstream; the two airstreams never touch, so there is no cross-contamination. A rotary wheel, by contrast, carries grease through its rotating matrix, where it bakes on, breeds fire risk, and cross-contaminates supply with exhaust. Our rotary vs plate comparison and the field guide where wheels are banned both point the same way: for kitchens, specify a plate (or heat-pipe) core, never a wheel. The moisture question — kitchens are latent-heavy — is covered in sensible vs latent recovery: a sensible plate controls temperature but not humidity, which is usually fine because the hood already manages grease-laden vapor.

System Layout

1. Fit a grease filter and UV/electrostatic scrubber upstream of the core so the exchanger sees cleaned, cooled-ish air.
2. Route exhaust through the core, make-up air through the other side (counter-flow plate for best effectiveness).
3. Add a summer bypass so the core is skipped when no heat recovery is wanted.
4. Size the make-up fan for the core pressure drop — see our pressure-drop reference.

What to Specify

Payback

With gas or electricity at typical commercial rates, a kitchen heat-recovery core usually pays back in 1–3 heating seasons, faster in cold climates and 24-hour operations. For a duty-specific payback estimate and drawings, contact +86 15753355505.