Ohio HVAC marketing for a furnace state, from the OH LIC# line to the no-heat call

Ohio tells a licensed HVAC contractor exactly how its license number must look and where it must appear. Put it right on the vans, the ads and the contracts once, and nobody has anything to point at.

Ohio's license display rule sets the format: OH LIC# and then the number. It reaches business cards, contracts, ads and any vehicle that carries the company name. A directory listing counts once it says more than your name, address and phone number. Pens, shirts and hats do not count.

• Vans. The number goes on at least two sides, in figures at least two inches high, placed so it is easy to notice. A wrap that tucks it under a door handle misses the point of the rule.
• One number, one name. The rule also bars advertising one license number for more than one business name. A shop that runs a second brand for budget installs should settle this before that brand gets its own Google profile.
• Landing pages. The rule covers advertisements, so we put OH LIC# in the footer of every page an ad sends people to, not only on the homepage.

Which number you hold depends on the work. Ohio's contractor definitions tie the state HVAC license to construction projects, and that term leaves out one-, two- and three-family homes. So a shop that only works on houses may hold a city or county license or registration instead, and no OH LIC# at all.

Cities may license or register heating contractors under Ohio's municipal licensing law. A city may charge a state licensee a registration fee, but it may not make one sit another exam. Counties can now license HVAC contractors who do not need the state license, in unincorporated areas and in cities that sign on, under a 2025 county licensing change. Check each city and county before its service area page goes live.

The words in the ad matter too. Ohio bars anyone from claiming to be a licensed type of contractor without that license. So "state licensed" belongs only to a shop that holds the state license. A residential shop can name what it does hold, such as a city registration. That same law lets an HVAC licensee run control wiring under 25 volts for its own equipment without an electrical license, which makes a smart thermostat page a natural fit.

When a technician sells a new system in the customer's home, Ohio gives the homeowner three business days to back out. The install generally waits until those days pass, which changes what a "same-day replacement" ad can honestly promise.

Ohio's home sales definition counts a sale made in the home even when the homeowner invited you in. The repair visit they asked for is outside it. A new furnace, a humidifier or a maintenance plan sold on that visit is not, beyond the parts the repair itself used.

The homeowner has until midnight on the third business day after the signature to cancel, by certified mail, hand delivery, fax or email, under Ohio's cancel law. Where the sale includes services, that law says the seller shall not start them while the buyer can still cancel.

The contract carries a bold notice in ten-point type, in the language the sales talk was given in, plus a detachable cancellation form in duplicate, under Ohio's notice law. The three days only start once those are given. On our reading, a sale talked through in Spanish with an English-only contract never starts the clock.

The emergency way out is narrow. The homeowner has to write the note personally, by hand, then date and sign it, and it has to describe the situation that needs immediate repair, under the home sales definition. A checkbox on a tablet does not look like that, on our reading.

So we write replacement ads around the visit and a realistic install window. "Installed this week" fits once the three days fit inside it. "Installed tonight" only holds when the handwritten statement is genuinely there. The federal three-day rule is on the HVAC page. Ohio's own law spells out the hold on starting work. Not legal advice; confirm with counsel.

Ohio is a heating state, but not evenly. The big metros differ by weeks at each end of winter, so one statewide budget spends at the wrong time in most of them.

Degree days are the usual yardstick for heating and cooling load. Columbus logs 5,233 heating degree days a year against 1,068 cooling degree days in NOAA's Columbus airport normals. Furnace work outweighs air conditioning there about five to one. The Ohio page covers drive times and borders. This is the heating and cooling side.

• Toledo. The coldest of the five: 5,641 heating degree days, 123 nights below freezing and 5.5 nights a year below zero in Toledo's airport normals. It also has the earliest median first freeze, October 24. Furnace ads start first here and run late into April.
• Cleveland. Its median first freeze waits until November 3 in the Cleveland airport normals, later than any of the others, with 63.8 inches of snow a year. The fall push can start a little later than Toledo's.
• Cleveland in spring. April still logs 447 heating degree days in Cleveland's monthly normals, against 367 at Columbus. Lakeshore furnace pages keep earning into May.
• Cincinnati. The weather station sits at the airport across the river in Kentucky. It logs the least heating of the five, 4,892 degree days, but 1,160 cooling degree days and 22 days a year at 90°F or above in the CVG airport normals. Cincinnati earns the biggest air conditioning share of the five.
• Dayton. July logs 341 cooling degree days in Dayton's monthly normals, the most of the five. Dayton's AC tune-up reminders can go out ahead of Columbus's.

Columbus has one more reason for its own budget. Its metro grew from 2,138,967 people in 2020 to 2,242,028 in 2025 in the Census Bureau's metro estimates, while Cleveland's shrank. On our reading, that means more households each year choosing a heating company for the first time, so Columbus gets more new-customer search spend and the shrinking metros lean on past customers.

Ohio has its own telephone sales law, with a registration, a bond and felony penalties. Most HVAC calls fall outside it, but only when the call books a visit instead of closing a sale.

Ohio's telephone sales definitions treat a seller's call that quotes a price or pushes a purchase as a solicitation. They exempt a call that sets up an in-home sale, where the presentation and the sale happen later, face to face. The exemption falls away if someone else collects payment after the call.

So "Your furnace is fifteen years old, can we come and look at it?" usually sits inside the exemption. Selling a maintenance plan over the phone and taking the card on that call does not.

• Registration. A caller who is not exempt must register with the Attorney General before dialing, under Ohio's registration section.
• Bond. It must also post a $50,000 surety bond, under Ohio's bond section.
• The first minute. Within the first sixty seconds the caller gives their name and company and says the call is to sell something, under Ohio's disclosure section.
• Penalties. Calling without registration is a fifth-degree felony, under Ohio's penalty section.

Referral offers have their own Ohio limit. The consumer sales law bars a reward for the names of prospective customers when earning it depends on something that happens after the purchase. On our reading, "refer a neighbor and get a credit when they buy" fits that description. A thank-you given for the referral itself, whatever the neighbor decides, is a different offer. Run the wording past your lawyer before it prints.

Recording booking calls is simpler. Ohio lets a party to a call record it, under its one-party consent law. A caller in Northern Kentucky or southern Michigan is under that state's law, which this page does not cover. Federal consent rules for marketing texts and recorded voices sit in our guide to texting and AI answering.