AI Search Optimization for HVAC Companies: What Gets Cited

The answer can reach a homeowner before your listing does. In a test by 5W, a PR and GEO agency, of 24 HVAC, plumbing and software questions on October 26, 2026, Google showed an AI Overview on 60 of 72 lookups (83.3%). In Pew Research Center's tracking of 900 U.S. adults' Google use in March 2025, people who saw an AI summary clicked a regular result in 8% of visits, against 15% when no summary appeared. That's Google use in general, not HVAC searches.

If the sites behind those answers show your old phone number or leave you out, you won't know until you look. You can look this week without hiring anyone.

Key points

• On two Cincinnati replacement questions on August 24, 2026, ChatGPT cited bbb.org in 11 of 12 answers. Gemini cited reddit.com in 10 of 12 and never cited bbb.org.
• In 5W's test, where no question named a city, the most-cited sites included modernize.com, consumeraffairs.com and bobvila.com.
• Neither test shows that a citation books a job. Fix what's blocked or wrong first, because those fixes help you either way.

Where should AI search optimization for HVAC companies start?

Start with your own test, using questions that name your town and questions that don't. The two dated samples below point to different sites.

What was counted	Town named (Vector Index, Cincinnati)	No town named (5W, national)
Date	August 24, 2026	October 26, 2026
Questions	2 HVAC replacement questions	24 HVAC, plumbing and software questions
Engines	ChatGPT, Gemini	ChatGPT, Claude, Gemini, Perplexity, plus Google AI Overviews
Chat answers	24	288
Most-cited sites in chat answers	ChatGPT: bbb.org (11 of 12), carrier.com (6), lennox.com (5). Gemini: apollohome.com (12 of 12), consumeraffairs.com (11), thomasgalbraith.com (11), reddit.com (10)	All four engines, share of answers grounded in web sources, leaving out the tracked brands' own sites: modernize.com (23.5%), consumeraffairs.com (20.0%), bobvila.com (18.9%), thisoldhouse.com (18.6%), youtube.com (15.1%)
Cited in AI Overviews	Not sampled	Share of the 60 overviews: youtube.com (40.0%), modernize.com (16.7%), reddit.com (13.3%)

The left column comes from Vector Index's local AI citations study, which asked "best HVAC company in Cincinnati for a new system" and "my furnace is 20 years old and I need to replace it in Cincinnati. Who should I call?" The chat answers in both samples came through the engines' APIs, and the consumer apps can answer differently.

Use the table to decide where to look. The samples differ in date, question mix and model versions, and each is a single day's reading, so it can't prove that naming a town caused the difference or predict your market. 5W's name counts track 28 brands, which means they can't show where a local shop stands.

What do these samples tell you to check first?

Your own site. Gemini cited apollohome.com in all 12 of its Cincinnati answers and thomasgalbraith.com in 11. Both are companies selling HVAC, plumbing and electrical services in Cincinnati and Dayton. The study counted domains, not pages, and didn't measure why an engine picked a site. Checking your service pages is our recommendation from that pattern, and the study didn't test it.

Your BBB profile. The study of what AI searches for logged ChatGPT running `site:bbb.org Cincinnati HVAC BBB Corcoran Harnist Heating Air`. It already had a company's name and went to a third party to check it. bbb.org isn't in 5W's published most-cited lists, so see whether it comes up on your own questions.

ConsumerAffairs and Reddit. These turned up in both samples. You can't edit a Reddit thread, but you can read what homeowners say about you there and look up your company on consumeraffairs.com.

YouTube. At 40.0% of 5W's AI Overviews it's hard to ignore, but that figure covers plumbing and software questions too. See whether videos appear on your own questions before you film anything.

How do you test your HVAC company's AI visibility yourself?

When you finish, you'll have a dated list of the sites each engine cites for your trade and town, plus a list of wrong or missing facts to fix.

1. Write six questions your customers ask across replacement, repair and no-heat calls. Half should name your town.
2. Ask each one in ChatGPT, Gemini, Perplexity and Claude with web search on, and run it in Google to see whether an AI Overview appears. Record the date, wording, model shown, every cited link and every company, noting whether each was named or actually recommended.
3. Ask again on different days with the same wording and settings. One answer is one reading.
4. Add /robots.txt to the end of your website's address and open it. If a section naming OAI-SearchBot blocks it, or there's no such section and the catch-all "*" section blocks everything, you're opted out. OpenAI's crawler documentation says opted-out sites "will not be shown in ChatGPT search answers," though they "can still appear as navigational links," and a change can take about 24 hours to register.
5. In Google Search Console, run the URL Inspection tool on each service page. Google's guidance on AI features says a supporting link "must be indexed and eligible to be shown in Google Search with a snippet."
6. Compare your name, phone, address, service area and license details across your website, your Google Business Profile and your BBB profile. Google's guidance tells site owners to check "that your Merchant Center and Business Profile information is up-to-date." Neither sample reports on Business Profiles, so nothing here measures how much one helps.
7. Open each service page. It should say in plain text what you install and repair, the brands you work on, the towns you serve and how to book.

Then fix things in this order. Access comes first (a robots.txt block, a page Google hasn't indexed). Wrong facts come next, because a bad phone number can lose the call even when the engine names you. Sites that keep recurring in your tests without you on them come last.

Hypothetical example: a two-truck heating and cooling shop moves across town. Its website shows the new phone number, but its BBB profile still shows the old one. If ChatGPT checks BBB and Gemini reads the shop's site, the same question could produce two versions of the company.

Are 87% of HVAC contractors really invisible in AI search?

Nobody should plan around that number yet. A May 2026 article in Plumbing & Mechanical, written around 5W's index, says "approximately 87% of independent HVAC and plumbing contractors have effectively zero AI citation share." It doesn't explain the calculation or define "effectively zero."

5W has since replaced that study with measured counts and says "the two versions are not comparable." Its current page doesn't show the 87% figure. We didn't find a published study that measures citation share for independent HVAC shops town by town, so if a vendor quotes a number like this, ask to see the count behind it.

Is this worth doing for a small HVAC shop?

The first pass needs no contract, and you or whoever runs your office can do all of it. A corrected phone number and an indexed service page help a homeowner even if no engine ever cites them.

Be careful with anyone who promises more. Google says "there are no additional requirements to appear in AI Overviews or AI Mode, nor other special optimizations necessary," and neither sample above measured whether a citation won a job. A vendor claiming otherwise should show you dated answers and what they compared them against.

Good AI search optimization for HVAC companies starts with a written record. Before you hire anyone or rewrite a page, read what an AI visibility audit should contain. You'll get the list of what any test has to record and the questions to ask a provider, so you can hold your own test, or anyone's, to the same standard.