You paid for an AC or furnace repair, the technician left, and a day or a week later the system is doing the same thing again, or something new has gone wrong. It's one of the most common home-service complaints. The good news is that most of these disputes are settled without a lawyer, if you handle them in the right order and keep a paper trail from the start.
This guide walks through the options from the least effort to the most, roughly in the order you should try them.
First: rule out a safety problem
If you smell gas, your carbon monoxide alarm goes off, or anyone in the home has headaches, dizziness or nausea that improve when they leave the house, stop troubleshooting. Get everyone outside, then call your gas utility's emergency line or 911. A furnace that was worked on and now has a gas or CO problem is an emergency, not a customer-service issue. You can deal with who pays afterward.
Step 1: Document everything, starting now
Most disputes are won or lost on documentation. Before anyone else touches the system, collect:
- The invoice and any written estimate, including the parts listed, the labor charged and any warranty language.
- Dates and times: when the repair happened, when the problem came back, and every call or message you've had with the company since.
- Photos and short videos of the equipment, the thermostat reading, and anything visibly wrong, such as ice on the refrigerant lines, water around the unit or error codes on the furnace board.
- Payment records: your card statement, a cleared check or a receipt.
Keep a simple log: date, who you spoke with, what they said. It feels tedious, but a dated log is persuasive to everyone from a card issuer to a small claims judge.
Step 2: Give the original company a chance to fix it, in writing
Many HVAC companies warranty their labor for a period, commonly 30 to 90 days and sometimes a year, and replacement parts often carry their own manufacturer warranty. Check your invoice. Even with no written warranty, a reputable company usually wants to make it right, and a call-back is often the fastest fix.
Call, then follow up by email or text so there's a written record: "On [date] your technician replaced [part] for $[amount]. As of [date], the system is [describe the problem]. Please schedule a warranty visit." If they come back and fix it, you're done.
Giving them a fair chance also matters later. Card issuers and courts generally expect you to have tried to resolve the problem with the business first.
Step 3: Get an independent second opinion
If the company refuses, doesn't show up, or comes back and still can't fix it, have a different licensed HVAC company diagnose the system. Ask the second company to put its findings in writing, specifically:
- What is wrong now, and what caused it
- Whether the earlier repair was done correctly, and whether the part replaced was actually the problem
- What it will cost to fix
A written diagnosis from an independent technician is the strongest evidence you can have. It turns "I think they did it wrong" into "a licensed professional found the capacitor they installed was the wrong rating and the actual fault was the contactor."
Step 4: Send a demand letter
If the original company still won't make it right, send a short, factual demand letter by email and by certified mail. Include:
- What you paid for, when, and how much
- What went wrong, with a reference to the second opinion
- What you want: a refund of $X, a free return visit to complete the repair, or reimbursement of $Y you paid another company
- A deadline, typically 10 to 14 days
- What you'll do if they don't respond, for example file a complaint with the state licensing board and pursue the matter in small claims court
Keep the tone calm and specific. Many businesses settle at this stage because a clear, documented letter signals that you'll follow through.
Step 5: Dispute the charge if you paid by credit card
Credit cards give you real leverage. Under the federal Fair Credit Billing Act, you generally have two routes:
- Billing errors, such as being charged for work that was never done or charged the wrong amount. You generally need to notify the card issuer in writing within 60 days of the statement that first showed the charge.
- Quality disputes, where work was done but done badly. The law lets you assert the same claims against the card issuer that you have against the business, generally when the charge was over $50, the purchase was made in your home state or within 100 miles of your mailing address, and you made a good-faith attempt to resolve it with the business first.
Card issuers also have their own dispute processes and timelines, which are often more generous. Call the number on the back of your card and have your documentation ready. Debit cards, checks and cash offer much weaker protection. That's a good reason to pay contractors by credit card.
Step 6: File complaints that create pressure
- The state or local licensing board. Most states license HVAC contractors at the state level, and some license them locally. A licensing board can investigate, discipline, and in some cases order restitution. Search "[your state] HVAC contractor license complaint".
- Your state attorney general's consumer protection office. The AG usually won't take your individual case, but many offices mediate complaints, and a pattern of complaints can lead to enforcement.
- The Better Business Bureau. The BBB isn't a government agency, but it forwards complaints to the business and many companies respond to protect their rating.
Step 7: Check for a state recovery fund
Some states, including Arizona, Maryland, Virginia and Florida, run recovery funds that can reimburse homeowners harmed by licensed contractors. The rules are specific. The contractor usually has to have been licensed at the time, and many funds require a court judgment or a licensing-board decision first. If you're in one of these states, it's worth reading the fund's eligibility rules before you file anything else, so you don't miss a required step.
Step 8: Small claims court
If the amount is modest and the company won't budge, small claims court is designed for exactly this. You usually don't need a lawyer, filing fees are modest, and cases are heard quickly. Limits vary widely by state, from $2,500 in Kentucky and Rhode Island to $25,000 in Tennessee and Delaware. California's limit is $12,500 for individuals, and Texas's is $20,000.
Bring the invoice, your log, photos, the second company's written diagnosis, the demand letter and proof it was delivered. Winning a judgment and collecting the money are separate steps, though. A company that's still operating usually pays. One that has disappeared may not.
When to talk to a lawyer
Consider an attorney if the amount is above your state's small claims limit, if the bad repair damaged your home (for example, water damage from a condensate leak), or if anyone was injured. Many state and county bar associations run lawyer referral services with low-cost initial consultations.
One thing not to do
If you haven't paid yet, be careful about simply refusing to pay. In many states, contractors can file a mechanic's lien against your property for unpaid work, which can complicate a sale or refinance. It's usually better to pay the undisputed portion, dispute the rest in writing, and follow the steps above.
Frequently asked questions
Can I hire another company to fix it and send the first company the bill?
You can ask, and it's a common demand-letter request. But the first company isn't obligated to pay unless you win a judgment or they agree. That's why the independent written diagnosis and the demand letter matter. They're what you'd use to prove the claim.
How long do I have to take action?
Card dispute windows are short, often 60 days from the statement for billing errors, so act quickly on that front. Deadlines for legal claims (statutes of limitations) vary by state and type of claim and are usually measured in years, but don't wait. Evidence and memories fade.
What if the original repair voided my equipment warranty?
Improper installation or non-approved parts can affect a manufacturer's warranty. Ask the manufacturer directly, in writing, and include any denial in your dispute with the contractor.
What does a fair HVAC repair cost?
Use our HVAC repair cost calculator to see typical ranges for your system and problem. It's a useful reference point when you're deciding whether a charge was reasonable.