Restaurant Kitchen HVAC and Makeup Air — Dallas Operator Guide

Kitchen exhaust without makeup air creates negative pressure, comfort complaints, and humidity problems. Here's how to do it right in Dallas. Call 214-238-4349 for a site walk.

Why Restaurant Kitchens Are an HVAC Problem on Their Own

A commercial kitchen exhaust hood typically pulls 1,500-4,000 CFM of air out of the building. Without an equivalent supply of conditioned fresh air ("makeup air"), the kitchen creates negative pressure that:

Pulls humid outdoor air through every gap in the building envelope (dining room door, exterior windows, HVAC infiltration)
Reverses bathroom exhaust flow (CO2 and odors recirculate back into the dining area)
Spikes dining-room humidity to 65-70% RH during service
Forces the cooling system to fight infiltrating outdoor air it was never sized for
Creates uncomfortable drafts at storefront entries

Most "kitchen too hot during dinner service" and "dining room humid even though AC is running" complaints in Dallas restaurants trace back to inadequate makeup air strategy — not undersized cooling equipment.

ASHRAE 62.1 and Why It Matters

ASHRAE 62.1 is the commercial ventilation standard governing fresh-air requirements per occupancy type. For restaurant applications:

Kitchen (food preparation): 0.7 CFM per square foot
Dining room: 7.5 CFM per person + 0.18 CFM per square foot
Bar / lounge: 7.5 CFM per person + 0.18 CFM per square foot
Exhaust hood: Typically 200-400 CFM per linear foot of hood — significantly larger than the supply requirement

The exhaust requirement drives the makeup air design. Without dedicated makeup air, the building tries to satisfy the exhaust through infiltration — which fails on humidity, comfort, and energy cost.

For broader Dallas commercial HVAC humidity context, see Why DFW's Air Is Getting Stickier (Part 1) and DFW Humidity Damage by Home Era — the commercial RTU short-cycling pattern applies to restaurants specifically.

How Makeup Air Should Work

A properly-designed Dallas restaurant HVAC includes:

1. Dedicated makeup air unit (MAU) tied to hood control. The MAU draws outdoor air, filters and conditions it (tempers temperature, often dehumidifies), and supplies it to the kitchen near the exhaust hood. CFM matches the hood exhaust rate.

2. Separate dining-area HVAC that doesn't try to compensate for kitchen ventilation. Typically Mitsubishi P-Series light commercial, Mitsubishi MXZ multi-zone (for smaller dining rooms), or commercial VRF for larger operations. More on Mitsubishi P-Series →

3. Variable hood operation linked to cooking activity. Hoods run at reduced CFM when not actively cooking, full CFM during peak service. Variable MAU operation matches.

4. Dining-area dedicated outdoor air (DOAS) — separate from kitchen MAU. Provides ASHRAE 62.1-compliant fresh air for dining occupants without depending on infiltration.

5. Pressure relief for bar and dining areas. When kitchen exhaust runs high, conditioned dining-area air relieves to outside through dedicated paths — not through bathroom exhaust or storefront infiltration.

A Real Example — Design District Restaurant Case Study

For a real Dallas project showing the makeup air problem and the multi-zone Mitsubishi solution, see our Design District Restaurant Mini-Split Case Study. That project (4,800 sq ft adaptive-reuse restaurant) replaced a single 7.5-ton RTU with three Mitsubishi MXZ multi-zone systems plus dedicated kitchen makeup air. Before/after results:

Kitchen line temperature dropped from 92-95°F to 78-82°F during peak service
Dining room held ±1.5°F of setpoint across an entire evening regardless of occupancy
Operating cost reduced approximately 30% versus the previous RTU
Patio became conditioned space (added 30 patio covers' worth of revenue capacity)

The architecture: Mitsubishi multi-zone for dining/bar/patio + dedicated kitchen makeup air. Both pieces necessary.

Equipment Standard for Dallas Restaurants

Dining and bar:

Mitsubishi MXZ multi-zone (for smaller restaurants under 4,000 sq ft) — independent zones for dining areas, bar, and patio
Mitsubishi P-Series light commercial (medium restaurants) — ducted or ducted-ductless hybrid
Mitsubishi CITY MULTI VRF (larger restaurants and chains) — multi-zone commercial VRF

Kitchen makeup air:

Dedicated makeup air unit tied to hood control
Direct-fired or indirect-fired gas-heated (or electric) for cold-weather tempering
DOAS integration for dining-area fresh-air supply

For broader commercial context, see Commercial HVAC Design District Dallas and Industrial Warehouse HVAC Design District.

Common Restaurant HVAC Failures

1. RTU-only HVAC trying to serve kitchen and dining. Single-zone single-stage rooftop unit can't satisfy diverse load profiles. Replace with multi-zone or VRF.

2. No makeup air strategy. Kitchen exhaust pulls air from infiltration. Comfort and humidity fail. Add dedicated MAU.

3. Hood oversized for actual cooking load. Pulling too much air costs energy. Right-size the hood; add variable-speed operation linked to cooking sensors.

4. Dining-area AC short-cycling. Single-stage AC oversized for low-occupancy hours, undersized for full service. Inverter-modulating equipment matches actual load.

5. No condenser placement strategy. Outdoor units crammed near kitchen exhaust draw hot, greasy air. Plan condenser placement away from exhaust streams.

Get a Restaurant Project Consultation

If you operate or are developing a Dallas restaurant — Design District, Bishop Arts, Deep Ellum, Uptown, Trinity Groves, Lower Greenville, anywhere — the conversation starts with a site walk evaluating exhaust load, dining occupancy, ASHRAE 62.1 compliance, and current HVAC architecture.

Call 214-238-4349 or request a site walk.

Truficient is a Mitsubishi Diamond Dealer with light-commercial restaurant HVAC capability across Dallas.