How to Spot and Avoid HVAC Repair Scams

HVAC repair scams are more common than most homeowners realize. The industry has its share of bad actors. We’ve heard from enough North Bay homeowners over the years to know the most common tactics. Here’s what to watch for — and how to protect yourself.

The Fake Cracked Heat Exchanger

This is the most notorious HVAC scam in our area, and it’s been going on for years. The play goes like this: a company — often one advertising a very low service call fee — sends a technician who “inspects” your furnace and emerges with alarming news. Your heat exchanger is cracked, they say, and you’re at immediate risk of carbon monoxide poisoning. They recommend replacement, usually with urgency and a steep price.

Heat exchanger cracks are real and genuinely dangerous — but they’re also relatively uncommon, and diagnosing one correctly requires disassembling the furnace and careful visual inspection with proper lighting. A technician who makes this diagnosis in five minutes with the furnace intact is telling you a story.

If you’re told your heat exchanger is cracked, always ask to see the crack yourself. A legitimate technician will show you. If they can’t or won’t, get a second opinion before spending a dollar.

The $20 (or “Free”) Service Call

Legitimate HVAC service calls have a real cost — typically $75–$150 in our area — because a skilled technician’s time is valuable and proper diagnosis takes time and equipment. When you see a $20 service call advertised, understand that the technician who shows up is usually a commissioned salesperson, not a diagnostic technician. The $20 doesn’t cover their time — the sale does. Their job is to find something wrong that justifies an expensive repair or full system replacement.

Honest contractors charge reasonable fees for diagnostic work and give you straightforward findings, even when the news is good.

Red Flags to Watch For

• Unsolicited calls or door-knocks offering urgent “free inspections”
• Technicians who make alarming diagnoses very quickly without thorough examination
• High-pressure urgency: “You need to replace this today or it’s dangerous”
• Unwillingness to physically show you the defect they’re claiming
• No license number, or one that doesn’t check out on the CSLB website
• Quotes significantly higher or lower than two other estimates
• No written estimate before work begins

How to Protect Yourself

Verify the license. Every HVAC contractor in California must be licensed by the Contractors State License Board. Check any contractor at cslb.ca.gov before authorizing work.

Get a second opinion. If you’ve been told you need a major repair or full system replacement, call another company. A legitimate finding will be confirmed by a second set of eyes. At Adams, we give honest second opinions — and we’ve talked plenty of homeowners out of unnecessary replacements.

Ask for an itemized written estimate. Any contractor unwilling to put a quote in writing before starting work is a red flag.

Choose a company with a local track record. Word of mouth in a community matters. Ask neighbors, check reviews, and look for contractors who’ve been in the area for years.

Adams Heating & Cooling has served Sonoma and Marin Counties for over 56 years. If you’ve received a diagnosis or quote that doesn’t feel right, call us for an honest second opinion.