Central Oklahoma’s HVAC Experts
Heating, Cooling & Geothermal, Kingfisher & Beyond

Central Oklahoma summers regularly hit 100-110°F with relative humidity above 80% in July and August. That combination, extreme heat and high moisture, means your cooling system has to handle both sensible load (temperature) and latent load (humidity removal) simultaneously. A system designed for Denver’s dry heat will leave a Kingfisher home feeling cold and clammy in August because it was never built to pull that much moisture from the air. Oklahoma winters bring the opposite problem: ground temperatures that drop fast enough to cut a standard heat pump’s efficiency in half, plus ice storms that stress equipment that hasn’t been properly maintained. I’ve been diagnosing both extremes in this specific climate for 15+ years.

Most HVAC contractors in Oklahoma still size equipment using square-footage rules of thumb. The result is systems that are too large: they drop the temperature quickly, then shut off before removing enough humidity from the air. You end up cold but damp, and over time, that moisture feeds mold. The other consequence is premature compressor wear from short-cycling. A Manual J load calculation is the engineering standard that accounts for your home’s actual insulation values, window area and orientation, infiltration rate, ceiling height, and local weather data. Every replacement I do starts with one. It takes longer than a tape measure and a phone call, but it’s the only way to know what your home actually needs, not what a rule of thumb says it should need.

About six to eight feet below the surface in central Oklahoma, ground temperature holds steady at roughly 59-62°F year-round, regardless of whether it’s 108°F outside in August or 14°F in a January ice storm. That stable thermal mass is what a geothermal heat pump exchanges with instead of outdoor air. In summer it’s cool enough to reject heat efficiently; in winter it’s warm enough to extract heat even when a conventional heat pump would be struggling. The result is a system that runs at 300-500% efficiency year-round in exactly the conditions that hammer conventional equipment hardest. Oklahoma’s rural electric cooperatives, CKenergy, Canadian Valley, Central Electric, offer rebates up to $2,000 per ton of installed capacity. Oklahoma utility rebates remain active, CKenergy members qualify for up to $2,000/ton, OG&E customers up to $1,000/ton. A typical 3-ton install can qualify for $6,000-$8,000 in rebates before you factor in utility savings. I’m one of very few IGSHPA Accredited installers in the state, the certification that means the loop was engineered correctly for Oklahoma’s soil conditions, not just dug and filled.

The most common calls I get: AC running but not cooling, furnace that won’t start, warm air blowing from the vents, and water leaking from the air handler. In most cases these can be diagnosed and resolved in a single visit. I charge a flat $99 dispatch fee and $111 diagnostic, part of the $210 flat repair-call price. The $111 is not credited. Accept a written repair estimate within 10 days and I give the $99 dispatch fee back. No stacking fees, no surprises. If the repair cost is significant, I tell you before I start. If replacement makes more financial sense than repair, I’ll say so honestly and give you both options with real numbers.

Hartzell’s charges $111 diagnostic, part of the $210 flat repair-call price. Accept the estimate within 10 days and I give the $99 dispatch back. A $99 dispatch fee applies to every service call. Most common repairs run $150-$600 (based on 2025 Hartzell’s repair pricing data) depending on parts. Free estimates are available for new system installations. See my full HVAC pricing and fees.

Yes. Hartzell’s Heat & Air responds to HVAC emergencies in Kingfisher and surrounding central Oklahoma counties. Call 405-375-4822 any time for after-hours service.

I serve Kingfisher, Garfield (Enid), Canadian, Logan, Blaine, Major, and Oklahoma Counties, including the Oklahoma City metro, Yukon, Mustang, Piedmont, Edmond, El Reno, Guthrie, Enid, Fairview, and dozens of rural communities across northwest and central Oklahoma.

I install and service Trane, RunTru, Mitsubishi, Daikin, Carrier, American Standard, and ClimateMaster geothermal systems. I’m a Mitsubishi Diamond Dealer, Trane TCS SELECT dealer, and ClimateMaster GeoElite dealer, the top certification level for geothermal in Oklahoma.

Yes. I work with five financing partners, Synchrony, Wells Fargo Home Projects, Wisetack, JB Financing, and Klarna, to offer flexible payment options on new system installations. Ask about current promotional rates at 405-375-4822.

A standard A standard air conditioner or furnace replacement typically takes one day. A full system replacement (both indoor and outdoor equipment) usually takes 1-2 days. Geothermal installations take approximately one week for ground loop drilling and equipment setup.