AC maintenance in Mill Valley deals with two things the town has plenty of: trees and moisture. Outdoor units on wooded lots collect redwood needles and leaf litter over the cool months, and damp air keeps condensate drains and pans wet long enough for algae and growth to take hold. Hillside homes that catch the breeze may only need cooling on a few afternoons a year, which means a problem can sit unnoticed until the first warm day. A tune-up in spring clears all of that before you need the cooling.
What happens during the visit
1. Clearing the outdoor unit. We remove debris from the top grille, the coil face and the base pan, where needles collect and hold water against the cabinet. Then we clean the coil with a coil cleaner and low-pressure water, working gently so the fins stay straight.
2. The indoor side. We check the filter, the blower and the evaporator coil. In damp homes the coil and the drain pan are where a musty smell starts, so we look at both closely.
3. Condensate drain. We flush the drain line, clear algae from the trap and test the float switch. Where the furnace and coil sit in the crawlspace, a blocked drain can overflow unseen for weeks.
4. Refrigerant check. We measure the charge against the manufacturer’s figures. If it is low, there is a leak, and we tell you so rather than topping it up.
5. Electrical testing. Capacitor values, contactor, wire connections, motor amps and the disconnect. Parts that sit idle in damp air corrode and weaken.
6. Performance report. You get the readings, the temperature drop across the coil and a plain list of anything that needs attention, priced before any work.
Crawlspace and duct checks
Many Mill Valley homes have their ducts in a crawlspace. While we are down there, we look at the duct connections near the equipment and note any that have come apart or are lying in standing water; a disconnected duct sends cooled air under the house instead of into the bedroom. Duct problems that need more than a quick fix get a separate quote. If the air in the house smells stale or the registers look dusty, our indoor air quality and duct cleaning pages explain the options.
Timing
Spring is the right time for a cooling-only AC: it catches problems before the warm spells, and appointments are easier to get. If your system is a heat pump, it has been heating all winter, so add a fall visit to keep the heating side in shape; see HVAC maintenance in Mill Valley.
What you can do between visits
- Keep a two-foot clear zone around the outdoor unit and trim branches that hang over it.
- After heavy needle drop, switch the power off at the disconnect and brush debris off the top grille.
- Change the filter on schedule, and more often during renovation work.
- Keep supply and return grilles clear of rugs and furniture.
If the system already has a problem, book AC repair in Mill Valley instead of a tune-up. The full checklist is on our AC maintenance page, and the Mill Valley page covers the rest of our work in town.