Fast, Reliable Air Quality & Ventilation Across San Marino
Whole-home air quality and ventilation in San Marino runs $1,200–$4,800 for most retrofits, with ERV/HRV systems on the higher end due to custom routing through attics and closets. We’re typically on-site in San Marino within 45 minutes from our Sacramento base, and we’ve spent 16 years learning how California’s inland heat and estate-scale construction change what “good air” actually means. Call (855) 467-1888 for a free estimate.
San Marino’s 1920s–1950s estate homes weren’t built for modern HVAC. Plaster-and-lath walls, no original duct chases, and sprawling 3,500–6,000 sq ft floor plans mean every air quality job here is custom. Our Air Quality & Ventilation team has handled enough of these retrofits to know where the surprises hide.
Why Stonegate Heating & Air California Is San Marino’s Preferred Air Quality & Ventilation Company
We’ve earned 499 verified reviews at a 4.7-star average across 16 years in California’s HVAC market. San Marino homeowners find us because they’ve already dealt with contractors who treat a 5,000 sq ft Spanish Colonial like a standard tract home. We don’t.
Owner Jason Trent serves as Field Supervisor on jobs, not a back-office figurehead. That means when we’re routing ERV ductwork through a 1930s Tudor attic on Virginia Road, he’s checking that the plaster isn’t stressed and that the unit placement satisfies San Marino’s strict appearance codes. San Marino’s permit standards tightly restrict visible exterior equipment and roof penetrations. Jason’s presence on-site prevents the redesigns and delays that happen when a junior tech realizes too late that the condenser can’t go where they planned.
Our multi-brand fluency matters here too. San Marino estates often have three or four mismatched systems from decades of additions. We’re factory-trained or experienced on Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard. Whatever’s already in your basement or guest house, we can integrate with it.
Our Air Quality & Ventilation Services in San Marino
ERV & HRV System Installation
Energy Recovery Ventilators and Heat Recovery Ventilators are the right answer for San Marino’s tight, older homes, but installation is never straightforward. San Marino’s 1920s–1950s estate homes with plaster-and-lath walls and no original ductwork mean that air quality retrofits like ERV/HRV systems require custom routing through attics or closets, often needing multiple small units to serve sprawling floor plans. A single central unit rarely covers 4,000+ sq ft of irregular, multi-wing layout. We design zone-by-zone, using compact duct runs and inline fans where full-size ducting won’t fit. Typical ERV/HRV installation in San Marino runs $2,800–$4,800 depending on zones and routing complexity.
Whole-House Dehumidifier Installation
San Marino’s Santa Ana wind events push hot, dry air through plaster-and-lath cracks, but summer humidity still pools in conditioned basements and guest structures. On Canterbury Road, we retrofitted a whole-house dehumidifier into a 1930s Tudor estate that had three separate undersized AC units. Our crew integrated a Carrier Infinity dehumidifier with the existing zoned system, routing ductwork through a conditioned basement to maintain proper humidity without visible equipment on the roof. Dehumidifier installs in San Marino typically run $1,800–$3,200.
Air Filtration System Upgrades
Standard 1-inch filters clog within weeks in San Marino. The combination of Santa Ana wind-borne particulate, pollen from the San Gabriel Mountains, and fine dust settling through century-old plaster cracks overwhelms anything you’d buy at a hardware store. We install 4-inch and 5-inch media filters with MERV 13–16 ratings, or whole-house electronic air cleaners where the electrical panel can support them. Filter upgrades and cabinet modifications run $400–$1,200 in San Marino.
UV Air Purifier Installation
UV-C lamps mounted in ductwork or air handlers neutralize mold, bacteria, and viruses. In San Marino’s older homes, we often find microbial growth in evaporator coils that never fully dry due to oversized, short-cycling systems from past additions. UV purifier installation runs $600–$1,400, but requires careful placement. Smart-home integration fails when HVAC controls are incompatible with older home wiring; UV air purifiers and HRVs require custom low-voltage runs that we plan from the start.
What happens when you call
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A real person answersNo phone trees — you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in San Marino
We stock parts and have direct experience with Carrier, Trane, Lennox, and Goodman systems — the brands we most commonly encounter in San Marino’s estate homes. Carrier Infinity communicating equipment integrates cleanly with modern zoning and dehumidification controls, which matters when we’re unifying three mismatched units into one coherent system. Trane’s variable-speed air handlers pair well with ERV pre-conditioning. We don’t turn away other brands; our nine-brand coverage means whatever’s in your basement, we can service it without a two-week parts hunt.
Common Air Quality & Ventilation Problems We See in San Marino Homes
- Santa Ana winds overwhelm standard filters. Fine particulate and pollen push through plaster-and-lath cracks during fall wind events, causing 1-inch filters to load up in 10–14 days. Homeowners on Canterbury Road and Virginia Road call us when they notice dust resettling within hours of cleaning.
- Multiple mismatched units create pressure imbalances. Estates with detached guest quarters or converted basements added in the 1940s–60s often run three or four separate systems that were never load-calculated together. Stale air pockets form where supply and return don’t balance, especially in wing rooms far from any air handler.
- Smart-home integration fails on older wiring. San Marino homeowners expect Nest, Ecobee, or full home-automation control of air quality equipment. The reality is 1920s knob-and-tube or early Romex that can’t support modern low-voltage communicating systems without dedicated runs we install ourselves.
- Humidity control gaps in conditioned basements. Basements converted to wine rooms, gyms, or guest suites in mid-century additions hold moisture that upstairs AC units never address. The main floor reads 45% RH while the basement hits 65% and grows surface mold.
Pricing for Air Quality & Ventilation in San Marino, CA
A typical whole-house media filter upgrade in San Marino runs $400–$1,200. UV air purifier installation is $600–$1,400. Whole-house dehumidifiers range $1,800–$3,200. ERV/HRV systems, given the custom routing through attics and closets that San Marino’s plaster-and-lath construction demands, run $2,800–$4,800.
What moves you within these ranges: number of zones, whether we’re cutting into original plaster or finding alternate routing, electrical panel capacity for added loads, and San Marino’s permit and inspection timeline. The city’s appearance and equipment-placement rules sometimes require redesigns that add labor but protect your home’s exterior character.
We don’t quote over the phone for San Marino estate work. Jason Trent or a senior tech walks the property, checks existing equipment, and delivers an itemized estimate. Call (855) 467-1888 to schedule — estimates are free.
We Also Serve Cities Near San Marino
Our crews regularly cross between San Marino and neighboring San Gabriel, East San Gabriel, Alhambra, and East Pasadena. The San Gabriel Valley’s inland heat patterns, estate-style construction in the northern sections, and shared permit familiarity with San Marino’s standards mean techs who know one city move efficiently through all of them.
Serving San Marino, CA — Our Local Coverage Area
We’re based in the San Marino area and know this community well. Use the map below to see our service coverage — if you’re nearby, we can almost certainly help.
FAQs — Air Quality & Ventilation in San Marino
Yes, we route ERV ductwork through attics, closets, and conditioned basements rather than cutting original plaster. On a recent Virginia Road job, we used two compact ERV units with short flex-duct runs through a master closet and butler’s pantry to serve a 4,200 sq ft 1926 estate with zero wall demolition. Call (855) 467-1888 for a routing assessment — estimates are free.
Permit rules in San Marino restrict visible exterior equipment and roof penetrations, so we plan humidifier drain lines and any venting to exit through existing mechanical chases or basement walls rather than new exterior penetrations. The permit process adds 5–10 business days to scheduling but prevents mid-project redesigns. We’ve worked with San Marino building staff enough to know what they’ll flag before they flag it.
Three or four mismatched, undersized units from past additions often fail to move enough fresh air through sprawling floor plans, and none may be tied to outdoor ventilation. We typically find pressure imbalances and zero mechanical ventilation in these estates. A proper load calculation and ERV integration usually solves what more AC tonnage cannot.
For San Marino’s typical 800–1,500 sq ft conditioned basements, we install 70–130 pint per day whole-house dehumidifiers tied into existing ductwork. The 1940s Canterbury Road Tudor we referenced used a Carrier Infinity unit rated at 105 pints/day, integrated with zoned supply and return through the basement’s original utility chase. Exact sizing depends on basement volume, insulation condition, and whether there’s a wine room or gym adding moisture load.
Yes, but almost always with new low-voltage wiring we run specifically for the integration. San Marino’s older homes lack the C-wire or communicating-bus infrastructure that modern smart thermostats and UV controllers expect. We plan these runs during the UV installation rather than discovering the incompatibility after the fact. Most San Marino smart-home integrations we do pair UV status with Crestron, Control4, or Ecobee systems through dedicated low-voltage drops.
Written by Jason Trent, Owner and Field Supervisor at Stonegate Heating & Air California, serving San Marino and the San Gabriel Valley since 2009.