The People Behind the Work

A job starts with the truck. We park as close to the house as the driveway allows and run a hose from the truck-mounted vacuum to your main trunk line, usually at the furnace or air handler. That machine pulls the whole duct system under negative pressure, so debris moves toward the vacuum instead of into your living room. Then we seal every supply and return register with sheeting so the suction stays in the ducts. From there the crew works run by run: compressed-air whips and rotating brushes fed into each branch to knock loose what is stuck to the sheet metal or the inside of the flex, working from the farthest register back toward the trunk. Returns last, since they hold the most. We pull and inspect the blower compartment, check the filter slot, and look at the coil while we have the cabinet open. Before and after photos of the same spots, every time. A typical single-system house takes most of a morning. If we find a disconnected flex run, a crushed boot, or an old octopus branch feeding nothing, we show you on the spot.

We work on gas furnace and forced-air systems from Carrier, Trane, Lennox, Goodman, Rheem and American Standard, plus the heat pumps that have been going into remodels here. The calls we get most in San Mateo are rodent activity in crawlspace ducts, musty smell when the heat first kicks on in October, dust blowing out of registers after a kitchen or bath remodel, and soot complaints after a smoke week. Related work often comes up while we are under the house or in the attic. If supply runs are leaking into a vented crawlspace, cleaning them matters less than duct sealing. If the smell is coming off a dirty evaporator, that is coil cleaning, not duct work. A surprising number of dust complaints trace back to a filter slot that never sealed properly, or a filter nobody changed, which is a cheap fix we will tell you about rather than sell around. We also say no. If we open the system and the ducts are clean, we tell you that, charge for the inspection, and leave.

The San Francisco Peninsula gives us two duct realities side by side. Pre-WWII raised-foundation houses in San Mateo County almost always started with gravity furnaces or wall heaters and got retrofitted to forced air later, so the ducts were threaded into tight crawlspaces as an afterthought: undersized trunks, long flex runs, octopus remnants, sometimes asbestos-wrapped sheet metal we will not disturb. Postwar tract homes on slab run everything through the attic, either 1950s sheet metal or flex replaced somewhere in the last thirty years. Climate hits both differently than inland California. Fog-cooled summers mean systems sit idle for months while dust and crawlspace moisture settle, marine humidity keeps cold runs sweating and growing film, and then October through April the furnace pulls air across all of it. Add a long oak, pine, cypress and eucalyptus pollen window, constant teardown-rebuild dust, and September smoke that leaves fine soot on the first few feet of supply duct. Most stable households here are on a three to five year interval, tighter with crawlspace ducts, pets, or a recent remodel. On cost: what moves the number on this job is how many supply and return runs you actually have, whether the system is one zone or two, how tight the crawlspace or attic access is, and whether we find rodent contamination or flex that is torn badly enough to need replacement instead of cleaning. We walk the house and count runs before we quote, and air filter replacement gets handled while we are there.