Geothermal Water Heater and Desuperheater Installation in Oklahoma

By Dave Hartzell, Master HVAC, IGSHPA Accredited, ClimateMaster GeoElite dealer, 47 years in the trade. Hartzell’s Heat & Air, Kingfisher, Oklahoma. Updated October 3, 2026.

How does Hartzell’s hook a geothermal desuperheater to my water heater?

A small pump moves water from the bottom of your tank through a heat exchanger in the geothermal unit and back. That exchanger sits on the compressor’s hot discharge line, so the water picks up heat while the unit is running, typically 5°F to 10°F per pass according to ClimateMaster’s startup check. Your water heater still finishes the job when it needs to, and it stays in place as the backup. When the geothermal unit is off, the HWG pump is off too. In my HCP records, the work behind this is a hot water tank to geothermal hook-up, the recirculating pump, and the occasional desuperheater pump replacement.

How much hot water does a desuperheater supply in an Oklahoma home?

I will not promise a number for your house, because it depends on how many hours your heat pump runs and how much hot water you use. Here is what the people who build and study these systems say, and nothing more:

ClimateMaster’s homeowner FAQ advertises that a factory HWG can “save up to 50% on your water-heating bill.” That is the manufacturer’s figure, not a promise from me. In the Oklahoma summer, a geothermal unit runs a lot, which is when the desuperheater does the most.

Can Hartzell’s add a desuperheater to my existing geothermal system?

Sometimes. On the ClimateMaster Tranquility 30 TE series, the HWG with pump is a factory option built into the cabinet, and the model number tells me whether yours has it. For ClimateMaster outdoor split units there is a remote-mount AHWG module. If your unit was built without one, I look at what is there before I recommend anything. I am a ClimateMaster GeoElite dealer, and I also service WaterFurnace and GeoStar systems.

Does a desuperheater work with a gas water heater in Oklahoma?

Not by itself. ClimateMaster recommends an electric water heater, and says that with a gas, propane or oil water heater, a second preheat tank must be installed. If your tank is gas, I plan for that up front. ClimateMaster also calls for copper HWG piping only, and it says a desuperheater is not recommended where the water is extremely hard. If you are on a well, tell me, and I will look at the water first.

What about a dedicated ClimateMaster geothermal water heater?

Some ClimateMaster systems go further than a desuperheater. The Trilogy QE has a full-time hot water mode paired with an iGate Smart Tank that ClimateMaster says can store water at up to 135°F. That setup makes the most sense in a house that uses a lot of hot water, and I would rather show you ClimateMaster’s literature than promise you a number.

What does Hartzell’s charge for desuperheater work?

A desuperheater hook-up on a new geothermal install is priced in writing on the estimate, and the estimate on a new system is free. On an existing system, the geothermal diagnostic is $348 flat, any hour, and the same for my plan members. I check loop pressure, refrigerant charge, the desuperheater, controls and the heat exchanger, and you get a written report and a quote before I leave. Utility rebates on geothermal change by utility and program year: CKenergy pays up to $2,000 per ton in its territory, and OG&E’s Oklahoma residential rebates are closed for 2026. Tell me your ZIP code and electric utility and I will check the current official program before I quote an amount. I am IGSHPA Accredited, with 4.8 stars and 300+ Google reviews, and I work geothermal across Oklahoma out of Kingfisher.

“We don’t replace the loops. They last.”Dave Hartzell, Hartzell’s Heat & Air, Kingfisher

That matters here too: a desuperheater rides on a geothermal system that is built to be around a long time. In 700+ geothermal jobs in my records since 2017, I have not replaced a loop field. Read more: geothermal heat pumps, Oklahoma geothermal rebates 2026, what geothermal costs in Oklahoma.