Ductless systems are a common way to add comfort to homes in Novato, San Rafael, San Anselmo, Larkspur and Sausalito that were never built for central air. When one stops working, the cause is usually close to the indoor unit: a clogged filter or drain, a dirty blower wheel, a sensor fault or a leak at a refrigerant fitting. We repair, clean and install mini-splits, and every visit starts with a diagnosis and an itemized price before any work begins.
Common ductless AC repair calls
| What you notice | Likely cause | What it usually takes |
|---|---|---|
| Lights blinking, unit will not run | Sensor, fan motor, board or communication fault | Reading the fault code and testing that circuit |
| Water dripping from the indoor unit | Clogged drain, lost slope, failed condensate pump | Clearing and re-pitching the drain or a new pump |
| Weak airflow or a musty smell | Dirty filters, coil and blower wheel | Deep cleaning of the indoor unit |
| Runs but barely cools or heats | Low refrigerant, often a leak at a flare fitting | Leak search, repair and recharge |
| Outdoor unit silent | Power, control board or wiring between the units | Electrical diagnosis |
| Remote does nothing | Batteries, receiver or settings lock | Quick check, often no parts |
Flare fittings, where the copper lines connect to each unit, are a known leak point on ductless systems, especially when they were not tightened to the manufacturer’s torque. Our EPA-certified technicians find the leak and fix it before adding refrigerant.
Deep cleaning the indoor unit
Each indoor unit pulls room air across its own coil, so dust, pet hair and kitchen grease collect inside it. The washable filters catch only part of it. Over time the coil and the drum-shaped blower wheel grow a dark film that cuts airflow and smells musty when the unit starts. A deep cleaning removes the covers, bags the unit and washes the coil and the wheel with a coil cleaner, then flushes the drain. It is often the whole repair for a unit that has started to drip or smell.
Between visits, rinse the filters every few weeks during heavy use and let them dry before putting them back.
Where mini-splits fit Marin homes
- Homes with no ductwork. Houses heated by a wall furnace or an old gravity furnace have nowhere to send cooled air. A mini-split adds cooling, and efficient heat, room by room.
- Additions, garages and workshops. A new room or a converted garage often sits beyond the reach of existing ducts.
- Older homes where opening walls is not an option. The line set needs only a small hole through the wall.
- Hillside homes where long duct runs through crawlspaces and attics are hard to build.
- Zone control. Bedrooms, offices and living areas each get their own setting.
Planning an installation
We start by looking at the rooms: size, windows, sun exposure and how you use them. Each room is sized on its own, because a unit that is too large for a bedroom cycles constantly and does little to dry the air. Then we decide:
- The type of indoor unit - wall-mounted, ceiling cassette, floor console or a small concealed ducted unit.
- Placement, so air reaches the room without blowing straight onto a bed or a desk.
- The line set and drain route, the shortest clean path to the outdoor unit with a drain that falls the whole way.
- The outdoor unit location: on a pad or a wall bracket, away from piled leaves, direct salt spray near the water and the neighbors’ windows.
On installation day the line set is pressure-tested and evacuated, the system is charged and run in both heating and cooling, and we show you the controls. Most people get the most from a mini-split by leaving it at a steady setting rather than switching it off and on.
For a whole-house conversion, see our heat pump services; for brand notes, see Mitsubishi, Fujitsu, Daikin and LG. Town pages: San Rafael and Sausalito.