Hydro Royal Heat Pump Review: HR 110, HR 125 and HR 150 Compared

Last updated: September 2026

There are plenty of air source heat pump brands in the US, so why did I pick Hydro Royal for my American customers? It’s quite simple. They’re made in the USA and they come with a 10-year limited warranty. Anyone putting a 10-year warranty on a heat pump is confident in the build quality.

In this review I’ll go through the Hydro Royal range, what the numbers actually mean, which DIY builds they suit (and which they don’t), and how to plumb and wire one in.

The Hydro Royal range

There are three sizes in the residential range: the 110, 125 and 150. The names roughly reflect the heat output in thousands of BTU per hour. The two larger models also come as heat & cool versions, which can chill the water as well as heat it. There are three-phase versions too, and Hydro Royal lists larger international (50Hz) models separately.

Model	80/80/80 (not AHRI)	AHRI 80/63/80	AHRI 50/63/80
HR 110	115,000 BTU/h (~34kW), COP 6.8	99,000 BTU/h (~29kW), COP 6.0	66,000 BTU/h (~19kW), COP 4.0
HR 125	125,000 BTU/h (~37kW), COP 6.6	109,000 BTU/h (~32kW), COP 5.9	74,000 BTU/h (~22kW), COP 4.1
HR 150	142,000 BTU/h (~42kW), COP 6.2	124,000 BTU/h (~36kW), COP 5.4	85,000 BTU/h (~25kW), COP 4.0

These are the heat-only figures from Hydro Royal’s HR 110, HR 125 and HR 150 pages. The heat & cool versions are rated slightly lower. For example, parts4tubs.com lists the HR 150 heat & chill at 137,000 BTU/h (COP 6.0) at 80/80/80. I’ve converted to kW at 3,412 BTU/h per kW for readers outside the US.

Spec	HR 110	HR 125	HR 150
Min / max flow	20 / 70 gpm	30 / 70 gpm	20 / 70 gpm (heat only)
Recommended flow	45 gpm (about 10m³/h)
Plumbing	2in
Min amps / max breaker	37 / 40	37 / 50	40 / 50
Size (unit)	31 × 31 × 38in	31 × 31 × 42in	31 × 31 × 43in
Weight (unit)	219 lb (99kg)	234 lb (106kg)	234 lb (106kg)
Compressor / heat exchanger	Scroll / 100% titanium

What do 80/80/80, 80/63/80 and 50/63/80 mean?

This is the bit that trips people up. The three numbers are the air temperature (°F), the relative humidity (%) and the water temperature (°F). In the US, pool heat pumps are rated to AHRI Standard 1160, and its rating points are 80/63/80 (warm air) and 50/63/80 (cool air).

80/80/80 is 80°F air with 80% humidity. Humid air holds more energy, so this produces the biggest numbers, and Hydro Royal labels it as outside the AHRI 1160 standard. It’s fine as a guide, but when you’re comparing brands, compare AHRI 80/63/80 against AHRI 80/63/80. And if you’re heating in spring, fall or winter, the 50/63/80 figure is the one that tells you what you’ll really get: around two-thirds of the output at a COP of about 4.

That still means about 4 units of heat for every unit of electricity. A resistance heater gives you one. Hydro Royal points buyers to AHRI certification on the exact model number, and I’d do the same with any brand. It’s what lets you compare apples with apples.

What’s good about the Hydro Royal?

• Made in the USA, with a 10-year limited warranty. The parts4tubs.com listings also state a lifetime warranty on the titanium heat exchanger.
• 100% titanium heat exchanger with rifled (“Turboguard”) tubing. Titanium doesn’t corrode in chlorinated or salt water, and the twisted tube gives more surface area and turbulence than a plain tube, so it transfers heat better in a compact unit.
• Scroll compressor, which is quiet and durable.
• Dual pool/spa programmable thermostat. This is a genuinely useful feature on a pool and spa combo, where you want the pool at one temperature and the spa at another.
• A non-rusting polymer cabinet with a raised base and a top fan that draws air over the whole coil.
• Remote control compatible. Hydro Royal also lists a Compass WiFi controller.
• Heat & cool options on the 125 and 150. These are great in hot climates, where a plunge pool or spa can get too warm in summer.

What to watch out for

• It’s overkill for a small hot tub. A single-seat or small backyard tub doesn’t need 30kW of heat. Where these shine is a plunge pool, cocktail pool, swim spa or a pool with a spa attached. For a standard hot tub, a smaller unit is cheaper to buy and easier to feed with water.
• Flow. The minimum is 20–30 gpm, depending on model, and the recommendation is 45 gpm. Size the pump and plumbing for that, and don’t expect a small 24/7 circulation pump to drive it. See how to correctly size a hot tub pump and can I use a variable speed pump in a hot tub?
• It isn’t marketed as an inverter. As far as I can see from the spec sheets, it’s a fixed-speed scroll design, so it runs at full output and then stops rather than throttling back. On a big body of water that’s fine. On a small tub it will cycle a lot.
• The warranty has conditions. Hydro Royal says warranty service must go through an authorized service center, and you’ll need proof of purchase. Register it and keep your paperwork.
• Refrigerant. Older literature says R-410A. Hydro Royal’s current pages don’t state the refrigerant, so check the data plate or ask before you buy if it matters to you or your installer.

Installing one on a DIY build

1. Location. Put it on a level pad, with clear space around the coil and nothing above the top fan. Keep it close to the equipment pad to keep the pipe runs short.
2. Plumbing. Put it after the filter and before any chlorinator or other heater, in 2in pipe, with a bypass (three valves) so you can set the flow and isolate it for service. If your pump pushes more than 70 gpm, the bypass is essential.
3. Electrics. It needs a dedicated circuit sized to the data plate (37–40 minimum amps, with a 40–50A maximum breaker depending on model), a disconnect within sight, and bonding in line with NEC Article 680. Use a licensed electrician and pull a permit where your county requires one. There’s more in a guide to hot tub electrics and what is ground bonding?
4. Control. Decide whether the heat pump’s thermostat or your spa pack is in charge, and make sure the heat pump only runs when water is flowing. I’ve explained the options in how to control a heat pump with any hot tub spa pack.
5. Keep the heat in. A cover and insulation make more difference to running costs than any heat pump. See DIY hot tub insulation.

If you’re still deciding between a heat pump, gas and electric, what is the best method to heat my DIY hot tub? and hot tub gas heaters set out the trade-offs. For sizing, read how to choose the right air source heat pump for your hot tub or pool, and for the bigger picture, the ultimate guide to air source heat pumps for hot tubs. For a UK comparison, there are my Comfortline and Vian Power reviews.

Where to buy a Hydro Royal

The Hydro Royal range is available in the USA on parts4tubs.com. These are the September 2026 prices, so check the listing for the current price:

Model	Price
Hydro Royal HR 110	$3,995
Hydro Royal HR 125	$4,295
Hydro Royal HR 150	$4,595
Hydro Royal HR 125 (heat & chill)	$4,895
Hydro Royal HR 150 (heat & chill)	$5,195

These are USA (60Hz) models only. For the UK and Europe, look at the Comfortline or Vian ranges on parts4tubs.co.uk instead.

Planning a plunge pool or pool and spa?

A Hydro Royal is a natural fit for a DIY plunge pool, and it’s much easier to plan the heat pump, pump and 2in plumbing in from the start. My plunge pool plans give you the drawings and plumbing layout, and there are swim spa plans too. If you’re designing something custom, like a pool with a spa attached, I can draw it up for you as architectural CAD with a 3D plumbing design, including the heat pump.

FAQs

Is Hydro Royal still in business and making heat pumps?

Yes. As of September 2026, Hydro Royal lists the HR 110, HR 125 and HR 150 (plus heat & cool versions) as current residential models, made in the USA.

What warranty does Hydro Royal offer?

A 10-year limited warranty, with service through authorized service centers and proof of purchase required. The parts4tubs.com listings state a lifetime warranty on the titanium heat exchanger.

Is a Hydro Royal too big for a hot tub?

For a typical hot tub, yes. They’re pool-sized heaters. They make sense for plunge pools, swim spas and pool and spa combos, where there’s enough water and flow to use the output.

What size breaker does a Hydro Royal need?

Hydro Royal lists 37 minimum amps with a 40A maximum breaker for the HR 110, 37/50 for the HR 125 and 40/50 for the HR 150. Your electrician sizes the circuit from the data plate and local code.

Can a Hydro Royal cool the water?

The heat & cool versions of the HR 125 and HR 150 can. The standard models are heat only.

Got a question about heating your pool or spa? Drop it in the comments below. I read them all.

Cheers,
Andi

You can also find me on my socials;

Can I Help You?

If I can help you in any way I would love to hear from you. You can get in touch using the form below.

Thanks - Andi

 

Hi, Andi here. I own Buildahottub.com and also write all of the articles and info pages on the site. Some years back now, I built my own hot tub but struggled to find the information I needed. So, once my tub was complete, I started this website to help others in their own pursuit of hot tub and plunge pools DIY building information.

Fast forward to 2025, I've helped over 1400+ DIY customers just like you all over the world build hot tubs and pools. Have a good look around the site, there are lots of resources here. Please do get in touch if I can help you. - Cheers, Andi