Air Duct Cleaning & Dryer Vent Cleaning in Mill Valley, CA

Mill Valley has always been a heating town, but that is changing. Summers here have been running hotter and more houses are putting in cooling than at any point we have seen. That matters for this work, because a system that only ever heated becomes a different machine once you ask it to cool. Cooling pulls damp air across a cold metal coil for months at a stretch, and the dust in that air sticks to it.

The older pattern is still the common one though. Fog sits in this canyon much of the year, redwood shade keeps the ground from drying out, and a furnace that runs a few months out of twelve spends the rest of the year sitting still in a dark, slightly damp space. What people notice is the smell in early October the first time it kicks on. Gone within the hour, back the next morning. Sometimes the ducts are the fix. Often it is the cabinet the fan and coil sit in, down at the bottom of the system where everything that settles ends up, and a vent-only cleaning never touches it.

Steep lots matter most on the laundry side here. A dryer venting twenty or thirty feet up through hillside framing, with several bends in the run, holds lint in a way a short straight vent through an exterior wall does not. Call today for a free quote on residential air duct cleaning in Mill Valley.

Adding Cooling to a House That Only Ever Heated

Putting cooling into a Mill Valley house that was built to heat changes what the system does to itself. Heating just moves warm air. Cooling pulls humid air across a coil that is colder than the dew point, which means it is pulling water out of the air, and that water has to go somewhere. It collects in a pan under the coil and drains out through a line that is easy to forget exists. When that line clogs, and it does, the pan backs up and you have standing water inside the cabinet with a fan blowing across it. That is how a system starts smelling like a basement in July. The coil, the pan and the drain are three of the nine components a proper job covers, and on a converted heating system they are the three most likely to be neglected, because nobody who serviced the house before cooling went in ever had to think about them. Systems over in Tiburon run into the same thing with salt in the mix.

What a Filter Can and Cannot Do

People often ask whether a better filter would have prevented this. Partly. A filter catches what is moving through the return, so a good one keeps new dust out of the system, and changing it on schedule is the single cheapest thing you can do for your air. What a filter does not do is remove what is already sitting in the ducts, on the fan blades, or on the coil. It also cannot help with anything entering downstream of it, which includes a duct run that has a gap in a damp crawl space. And a filter that is too restrictive for the system starves it for airflow, which makes the equipment work harder and can push air around the edges of the frame instead of through it. Denser is not automatically better. Match the filter to what the system is rated for, change it, and treat that as maintenance rather than as a substitute for cleaning.