Lennox HVAC in Loomis, CA | Redwood Heating & Air San Diego
Lennox furnace and AC repair in Loomis typically runs $150–$700 for most fixes, with same-day service available for urgent propane-system failures. We’re an independent Lennox service company, not a manufacturer-authorized dealer, which means we work on every Lennox model line in Loomis without pushing new equipment you don’t need. Call (844) 875-9451 for a free estimate.
Our technicians carry OEM parts for Signature SL, Elite EL, and Merit ML series units, and we understand the propane-specific issues that dominate Loomis’s semi-rural HVAC calls. From Horseshoe Bar Road ranchettes to custom homes off Sierra College Boulevard, we’ve diagnosed Lennox systems through 100°F foothill summers and hard January freezes for 13 years.
Why Loomis Residents Choose Us for Lennox Service
Gregory Hahn founded this company and still leads every technical decision. He grew up in Mira Mesa patching ductwork with his uncle, trained in HVAC diagnostics at Miramar College, and has spent 13 years building Redwood Heating & Air into a shop that diagnoses right the first time. That matters in Loomis, where a Lennox furnace on propane isn’t a generic gas call. It’s a system with regulator pressure, orifice sizing, and line diameter specs that change how we approach every repair.
We’re certified to service nine major HVAC brands, including Lennox, which means we won’t try to sell you out of your current system just because we don’t stock the part. Our Lennox sales & service work covers everything from a 25-year-old ML180UH on a horse property to a new SLP98V modulating furnace in a custom build. We keep OEM components in stock for Signature and Elite models, and we source quality approved aftermarket parts for older Merit units when that makes more sense than chasing discontinued factory inventory.
428 verified reviews averaging 4.6 stars. 13 years in business. Gregory’s Master Technician credential is on the truck, not locked in a corporate office. If I wouldn’t put it in my own house, I’m not recommending it for yours.
Common Lennox HVAC Problems We Solve in Loomis
- Mercury heat exchanger cracking from propane regulator creep. On older Loomis properties with above-ground propane tanks dating to the 1970s, regulator pressure can drift above 11 inches WC. We’ve found this creeping to 12 inches or higher on rural parcels off Horseshoe Bar Road, overfiring the burner and cycling thermal stress through the heat exchanger. The Signature SL280UH and older Merit furnaces with Mercury-series exchangers are particularly vulnerable. We check tank pressure and line sizing before we touch the gas valve.
- SLP98V secondary heat exchanger corrosion. That 98% AFUE modulating furnace condenses aggressively, and in Loomis propane homes without a condensate neutralizer, the acidity eats the secondary cell from the inside out. We see this on properties where the condensate line dumps straight to a floor drain or gravel pad. Replacement requires the OEM secondary kit, not a generic swap.
- ML180UH nuisance lockout from undersized propane orifices. A Roseville tech running natural gas all year might not catch this. In Loomis, where 100°F summer days drive high fire rates, an orifice sized for a lower BTU content or different manifold pressure causes the flame sensor to drop out. We measure gas valve outlet pressure and orifice diameter against Lennox’s propane spec chart, not the natural-gas sticker still on the door.
- ML14XC1 compressor start capacitor failure after hard freezes. Loomis hits genuine single-digit nights that Roseville rarely sees. Without a low-ambient kit, the compressor tries to start against thick refrigerant oil and fails repeatedly. The capacitor takes the abuse and opens. We stock the OEM Lennox start capacitor and hard-start kit for this exact call, because it happens every January.
- Ductwork undersized for vaulted ceilings and large floor plans. Loomis custom homes from the 1980s and 1990s often have exposed-beam great rooms with 18-foot ceilings. The original Lennox AC installer may have sized for a standard 8-foot ceiling. We see static pressure readings above 0.5 inches on systems that never reach setpoint on 105°F August afternoons. Our fix starts with a Manual J recalculation, not a bigger compressor.
Lennox Service in Loomis: What Local Conditions Mean for Your Equipment
Loomis’s semi-rural parcels often rely on propane gas stored in above-ground tanks, requiring furnace technicians to check regulator tank pressure and gas line sizing (often 3/8-inch versus 1/2-inch) before any Lennox furnace repair. A step rarely needed in natural-gas-dominant neighboring Roseville, where Lennox systems run on standard utility gas. On a call off Horseshoe Bar Road, we found a 20-year-old Lennox ML180UH furnace cycling off on high-limit after 10 minutes. The propane supply lines metering up to 12 inches WC at the regulator instead of the rated 11, and sediment from a 1980s tank was fouling the gas valve. We flushed the line, replaced the gas valve with a factory Lennox part, and reset regulator pressure to spec. The homeowner’s morning temperature was back to 71°F by the next freeze.
This is the reality of Loomis Lennox work. The Sierra Nevada foothills swing from 100°F summer highs to hard winter freezes that Sacramento and Lincoln barely experience. The I-80 corridor funnels wildfire smoke through every fire season, pushing our customers toward MERV 13+ filtration and whole-home air cleaners. And the housing stock, custom-built on large lots from the 1970s through the early 2000s, has almost none of the uniform tract construction that lets a technician guess at duct layout. Every Manual J load calculation, every propane orifice spec, every low-ambient heat pump rating is site-specific. That’s why we don’t send rookies to Loomis.
Lennox Models & Products We Service in Loomis
We maintain factory training certifications in Lennox Signature and Elite systems and stock OEM-specific components for the model families that show up most in Loomis:
- Signature SL Series: SL280UH variable-speed gas furnace, SL18XC1 two-stage AC. We keep the SureLight control boards, variable-speed blower modules, and two-stage pressure switches in stock.
- Elite EL Series: EL280UH two-stage furnace, EL16XC1 single-stage AC with two-stage compressor. Common failure points are the PSC blower motor capacitor and the two-stage gas valve.
- Merit ML Series: ML180UH single-stage furnace, ML14XC1 single-stage condenser. These are the workhorses on older Loomis properties. We prioritize OEM parts when available, but we’ll source quality approved aftermarket equivalents for discontinued components and tell you honestly when repair cost is approaching replacement territory.
- SLP98V modulating gas furnace: The most sophisticated Lennox furnace we service. Secondary heat exchanger, modulating gas valve, and communicating thermostat all require factory-trained diagnosis. We have the OEM test equipment and the parts library to match.
We’re independent and not authorized by Lennox. That means no corporate mandate to push new equipment, no restricted territory rules, and no incentive to declare your 12-year-old Elite system “unrepairable” because the factory wants the replacement sale.
Lennox Service Pricing in Loomis
| Service | Price Range |
|---|---|
| AC Repair | $150–$650 |
| Furnace Repair | $150–$700 |
| AC Installation | $3,500–$7,500 |
| Tune-Up | $80–$200 |
What drives cost? Propane system diagnostics take longer because we’re checking regulator pressure, line sizing, and orifice spec against the factory chart, not just lighting a pilot. Heat exchanger replacement on an SL280UH runs toward the high end because the cell is a factory-ordered component with a specific installation sequence. A simple capacitor or contactor swap on an ML14XC1 sits at the lower end.
Our free estimate includes a full system diagnostic, written repair quote with parts and labor separated, and an honest repair-vs-replace assessment based on your unit’s age and cumulative repair history. No obligation. Call (844) 875-9451 for an exact quote on your Lennox system.
Serving Loomis, CA — Our Local Coverage Area
We’re based in the Loomis area and know this community well, with Granite Bay Lennox service just minutes away. Use the map below to see our service coverage — if you’re nearby, we can almost certainly help.
FAQs — Lennox HVAC in Loomis
Yes, and the root cause is usually overfiring from excessive propane pressure or a partially blocked flue on a rural installation. We check regulator output and gas valve inlet pressure before we replace any switch. Call (844) 875-9451 and we’ll diagnose it same-day.
Yes. That symptom points to a failed start capacitor or compressor lock from a hard freeze without low-ambient protection. We stock the OEM Lennox capacitor and hard-start kit for this exact failure. We service properties throughout the Loomis rural zone, including off the I-80 corridor and nearby North Auburn.
Heat pumps lose capacity as outdoor temperature drops, and Loomis hits lows that push standard units below their balance point. We check your unit’s low-ambient rating and supplemental heat staging. Some Loomis installations need a dual-fuel setup or a cold-climate heat pump with enhanced vapor injection.
If the heat exchanger is sound and repair cost is under 30% of replacement, we fix it. At 25 years, we inspect the exchanger with a borescope and check for cracks or corrosion. We’ll show you what we find and give you real numbers. Call (844) 875-9451 for a free assessment.
Very possible in Loomis custom homes with vaulted ceilings and original 1980s ductwork. We measure static pressure and compare your duct layout to the Manual J load calculation your system should have had. Undersized ducts are fixable; we don’t default to upsizing the compressor.
Service Areas Near Loomis
We run Emergency & Commercial HVAC in Loomis calls throughout Placer County and into neighboring communities. Our regular service radius includes Lennox service in Rocklin for the denser subdivisions west of Loomis, plus Lennox service in Tulare for customers with secondary properties in the Central Valley. We also handle calls in San Diego, Olivehurst, Covina, Citrus, Fremont, and Azusa where existing customers have relocated or own rental units.
Book Your Lennox Service in Loomis Today
Gregory Hahn and our technicians are available for same-day Lennox service in Loomis when your propane furnace locks out or your ML14XC1 won’t start in a freeze. We’re independent, factory-trained on Signature and Elite systems, and we carry the OEM parts that keep your system running without the upsell pressure. Call (844) 875-9451 for a free estimate.
Written by Gregory Hahn, Owner at Redwood Heating & Air San Diego, serving Loomis since 2011.