Humidity and Moisture
Cold and clammy is a different problem than warm.
A house at 73 degrees can still feel wrong. Sticky air, windows that fog, a basement that smells like a basement, or the thermostat reading fine while nobody is comfortable. That is a moisture problem, and it will not be solved by setting the temperature lower.
Air conditioning removes moisture as a side effect of removing heat. When that side effect stops working, the temperature can still be right while the humidity is not.
Why a cold house can still be humid
Moisture comes out of the air when air spends enough time on a cold enough coil. Anything that shortens that contact reduces moisture removal.
An oversized system is the common one. It satisfies the thermostat quickly, shuts off, and never runs long enough to dry the house. The shorter the run time, the wetter the house. This is why an oversized system is a real defect and not a harmless margin of safety.
Air moving too fast across the coil does the same thing in a different way. So does a coil that is not cold enough because of a charge or airflow condition. So does moisture entering the house faster than the system can remove it, from a crawlspace, a bath fan that terminates in the attic, or an unbalanced duct system pulling humid outside air in.
What we measure
Indoor conditions including dew point, not just temperature. Airflow and static pressure. Temperature change across the coil and the conditions at the equipment. Run time behavior, because how long the system runs is itself a measurement.
Dew point is the number that matters here, and it is the one nobody takes. A thermostat's humidity reading is not a substitute.
What the answer usually is not
A whole house dehumidifier bolted onto a system that is oversized and short cycling is treating the symptom with more equipment. Sometimes added dehumidification is genuinely the right answer. It should be the conclusion of a measurement, not the opening move.
Envelope and duct testing
When the numbers suggest moisture is entering the house rather than failing to leave it, the next step is envelope or duct leakage testing. That is separate, approved work and is not part of the evaluation. We will tell you when it is warranted and when it is not.
Common questions
Common questions
- Should I just buy a dehumidifier?
- Maybe, but find out why the AC is not doing it first. If the system is short cycling, a dehumidifier masks a defect you are still paying to run.
- Is my system too big?
- It might be. That is a measurable question rather than a matter of opinion, and short run times with high indoor humidity are the pattern that suggests it.
- What humidity level should I have?
- Most homes are comfortable in the low to mid 50s percent relative humidity at normal indoor temperatures. Dew point is the more useful number and we will give you both.
- Does this cause mold?
- Sustained high indoor humidity creates conditions that support microbial growth. We are not a remediation company and we will not diagnose mold, but we can tell you whether the moisture conditions are in a range that invites it.