Q2 2026 | The Conduit: Connected Solutions for a Better Built Environment

Humidity in the Desert: Troubleshooting Clues

Humidity complaints are among the most expensive HVAC callbacks because the root cause often isn't where technicians first look.

Equipment gets replaced. Sensors get changed. Yet the real issue may be pressure relationships, outside air, or a thermostat override.

Humidity is largely misunderstood in the Southwest. Aside from critical environments, most of the year, buildings in Arizona, New Mexico, and West Texas are focused on cooling and ventilation and can ignore humidity altogether.

It's not because we're humid.

Because we think we're not.

Our Albuquerque case study from the last two newsletters shows just how simple errors can cost extensive money or damage.

INDOOR HUMIDITY LEVELS AND ASSOCIATIONS WITH REPORTED SYMPTOMS IN OFFICE BUILDINGS

Moderate indoor relative humidity (RH) levels (i.e., 40%-60%) may minimize transmission and viability of some viruses, maximize human immune function, and minimize health risks from mold, yet uncertainties exist about typical RH levels in offices ...

Humidity Costs More Than Complaints

When humidity is too high or too low, occupants often adjust thermostats to compensate or facilities teams spend all day answering comfort calls costing time and energy.

According to ASHRAE guidance, every 1°F thermostat adjustment can impact HVAC energy use by roughly 1-3%. For a typical commercial building, a 3°F comfort-driven change could add thousands of dollars per year in unnecessary energy costs.

Humidity control isn't just about comfort, it's about protecting budgets, building performance, and occupant satisfaction.

In addition to this, costs can show up in productivity, damage and more...

Not Enough Humidity

Static shocks

Dry eyes

Increased illness transmission

Cracked materials

Fatigue and discomfort

Too Much Humidity

Mold growth

Wet ceiling tiles

Rusted equipment

Condensation damage

Occupant complaints

Get Ahead of the Problem

Lessons From the Field

Common Mistakes and Practical Solutions to Troubleshooting

Humidity issues often involve equipment, controls, airflow, pressure relationships, outdoor air conditions, occupant behavior, and even water quality.

The best troubleshooting starts by understanding where humidity problems actually come from and how they can show up.

Below are a few Examples

Thermostat War

Lowering a room temperature doesn't remove moisture. In fact, lowering setpoints can bring surfaces closer to the dew point and create unexpected condensation.

In healthcare spaces, labs, and other critical environments, a few degrees can mean the difference between a comfortable space and a moisture problem.

⚠️ WATCH FOR

Space temperatures below design intent
Occupant overrides
Condensation on diffusers, windows, or walls
"Crying" drywall

✔ SOLUTIONS

Find out the control authority during design process to ensure adjustments with the system and expectations.
Limit temperature adjustment ranges
Trend dew point alongside temperature
Educate occupants on condensation risk
Use humidity-based reset strategies

💡

KEY TAKEAWAY

A colder thermostat does not remove moisture. It can move surfaces closer to dew point and create condensation problems.

The Missing Return

Air has to get back somehow.

One missing return grille can completely change how a room behaves. We've seen retrofit projects where supply air was added but return air was overlooked. The result wasn't comfort—it was pressure imbalances, trapped moisture, and condensation issues that looked like equipment failures.

⚠️ WATCH FOR

🚪 Doors difficult to open or close

🌬️ Uneven temperatures between spaces

📈 Room pressure complaints

💧 Condensation with units operating normally

✔ SOLUTIONS

⚖️ Verify supply/return balance

🏢 Check room pressure relationships

📐 Review retrofit drawings for airflow paths

🔄 Confirm transfer air routes exist

Water Quality is King

The humidifier is only as good as the water feeding it.

Steam, evaporative, atomizing, and adiabatic systems all have different water quality requirements. Scale buildup, mineral deposits, and untreated water can reduce capacity, increase maintenance costs, and shorten equipment life.

⚠️ WATCH FOR

Scale accumulation
Frequent maintenance calls
Reduced humidification output / low humidity readings or alarms on controls system
Water treatment issues

💧 FIELD LESSON

DON'T SKIMP ON WATER FILTRATION

Poor water quality can lead to scale buildup, inaccurate readings, and costly service calls in less than 6 months.

Monitoring the Wrong Controls Points

Monitoring, Trending & Alarming

Many humidity problems aren't caused by failed equipment. They're caused by missing visibility because the concept of humidity is challenging and people don't know what to look at, or look for, first. Let's make that full proof.

We've seen buildings trend only space humidity while ignoring the information needed to determine why humidity is changing.

Without the right points, troubleshooting becomes guessing.

WHAT YOU SEE...

➡️ Space humidity alarms with no obvious cause

➡️ Condensation that appears only during certain times of day

➡️ Occupant complaints during monsoon season

➡️ Humidifiers running continuously

➡️ Reheat operating excessively

➡️ Large humidity swings after occupancy changes

THE COMMON MISTAKE

TRENDING SPACE HUMIDITY ALONE

THE MISSING INFORMATION...