Pool Heaters for 10,000 Gallon Pools

Heat Pump Pool Heaters for Small Inground and Above Ground Pools

Every heater in this collection is a heat pump - meaning it runs on electricity, requires no gas line, and can both heat and cool your pool water. We carry models from FibroPool, Madimack, and Hayward across the 20,000 to 55,000 BTU range, sized for pools up to 10,000 gallons. Several models also cover pools up to 12,000 gallons, and those are included here as well. FibroPool models are compatible with above ground and inground pools. Madimack and Hayward HeatPro models are designed for inground pools.

Find the Right Heat Pump for Your Pool

Select your pool size below to see which models fit, estimated monthly running costs, and what sets each option apart.

My pool holds approximately...

Under 3,000 gal 3,000-5,000 gal 5,000-7,500 gal 7,500-10,000 gal 10,000-12,000 gal Spa heating

Select your pool size above to see recommendations.

Under 3,000 gal - recommended: 20,000 BTU

FibroPool FH120 - from $975 - approx. $15/mo (warm) or $22/mo (moderate) 110V
FibroPool FH220 - $1,146 - approx. $15/mo (warm) or $22/mo (moderate)

The FH120 runs on standard 110/120V household current - no dedicated circuit or electrician needed. The FH220 requires a 220/240V circuit but is otherwise identical in output. Both heat and cool.

3,000-5,000 gal - recommended: 20,000 BTU

FibroPool FH120 - from $975 - approx. $18/mo (warm) or $26/mo (moderate) 110V
FibroPool FH220 - $1,146 - approx. $18/mo (warm) or $26/mo (moderate)

Both FH120 and FH220 are rated for pools up to 5,000 gallons. If your pool is close to 5,000 gallons or is uncovered and exposed to wind, the FH135 is the next size up and worth considering.

5,000-7,500 gal - recommended: 32,000-35,000 BTU

FibroPool FH135 - from $956 - approx. $28/mo (warm) or $38/mo (moderate) 110V
FibroPool FH235-i - $1,470 - approx. $20/mo (warm) or $28/mo (moderate) Inverter
Madimack InverECO 32K - $2,110 - approx. $18/mo (warm) or $26/mo (moderate) Inverter

The FH135 is the most affordable and runs on 110V. The FH235-i adds an inverter compressor for quieter operation and lower monthly bills. The Madimack InverECO 32K is the premium option with WiFi and built-in spa mode - it can heat pool/spa combinations to 104 F.

7,500-10,000 gal - recommended: 40,000-55,000 BTU

FibroPool FH255 - from $1,853 - approx. $40/mo (warm) or $56/mo (moderate)
Madimack InverECO 40K - $2,450 - approx. $28/mo (warm) or $38/mo (moderate) Inverter

The FH255 at 55,000 BTUs heats up faster. The Madimack InverECO 40K costs more upfront but runs quieter and uses less electricity for day-to-day maintenance heating.

10,000-12,000 gal - recommended: 50,000 BTU

Madimack InverECO 50K - $2,680 - approx. $32/mo (warm) or $44/mo (moderate) Inverter
Hayward HeatPro 50K - $2,999 - approx. $42/mo (warm) or $58/mo (moderate)

Both are rated to 12,000 gallons. The Madimack uses an inverter compressor with WiFi and includes spa mode. The Hayward HeatPro is a standard single-speed unit - simpler, with strong warranty support and broad installer familiarity. In a cooler climate, consider sizing up to the InverECO 66K.

Spa heating - models with spa mode in this collection

Madimack InverECO 32K - $2,110 - heats pools up to 7,500 gal and spas to 104 F Inverter
Madimack InverECO 50K - $2,680 - heats pools up to 12,000 gal and spas to 104 F Inverter
Hayward HeatPro 50K - $2,999 - heats pools up to 12,000 gal and spas to 104 F

All three models are rated for both pool and spa use and can maintain spa temperatures up to 104 F. Heat pumps heat water gradually at 1 to 2 degrees F per hour - they work well for maintaining a spa already at temperature or for a pool/spa combination kept warm together. If you need a cold spa to reach 104 F quickly on demand, a gas heater is a faster option. Need a spa-capable heater for a larger pool? Browse the 20,000 gallon collection for additional spa-rated models.

Monthly cost estimates assume a moderate climate swim season and average US electricity rate of $0.17/kWh. Pool cover use reduces running costs by up to 40%. Models tagged with Spa support spa mode heating to 104 F. Call us at 800-809-3741 for personalised sizing advice.

Compare Pool Heat Pumps for Pools Up to 10,000 Gallons

All models below heat and cool. The main differences are BTU output, pool size coverage, inverter vs. standard compressor, voltage requirements, and price. FibroPool FH120 and FH135 run on standard 110/120V household current - no dedicated circuit needed. All other models require a 220/240V circuit.

Pool Size	Unit	BTUs	Type / Mode	Voltage	Price
Up to 5,000 gal	FibroPool FH120	20,000	Heat/Cool	110/120V	from $975
Up to 5,000 gal	FibroPool FH220	20,000	Heat/Cool	220/240V	$1,146
Up to 7,500 gal	FibroPool FH135	35,000	Heat/Cool	110/120V	from $956
	FibroPool FH235-i	35,000	Heat/Cool Inverter	220/240V	$1,470
	Madimack InverECO 32K	32,000	Heat/Cool Inverter	220V	$2,110
Up to 10,000 gal	FibroPool FH255	55,000	Heat/Cool	220/240V	from $1,853
Up to 10,000 gal	Madimack InverECO 40K	40,000	Heat/Cool Inverter	220V	$2,450
Up to 12,000 gal	Madimack InverECO 50K	50,000	Heat/Cool Inverter	220V	$2,680
Up to 12,000 gal	Hayward HeatPro 50K	50,000	Heat/Cool	240V	$2,999

Inverter models vary output based on demand - quieter, more efficient, longer lifespan than standard models. 110/120V models plug into any standard outdoor outlet. All other models require a dedicated 220/240V circuit. No gas line is needed for any model in this collection.

Frequently asked questions

How do I know if my pool is up to 10,000 gallons?

A rough formula for rectangular pools: length x width x average depth x 7.5 = volume in gallons. A 12x24 foot pool with an average depth of 4.5 feet works out to approximately 9,720 gallons. Round pools and irregular shapes have different formulas, but most small above ground pools (15 to 18 feet round) fall comfortably under 10,000 gallons. If you are not sure, call us at 800-809-3741 and we can help you estimate.

What is the difference between the FibroPool FH120 and FH220?

Both models are rated at 20,000 BTUs for pools up to 5,000 gallons and include heat and cool capability. The only difference is voltage: the FH120 runs on 110/120V standard household current, while the FH220 requires a 220/240V dedicated circuit. If your pool area does not have a 220V outlet and you want to avoid electrical work, the FH120 is the simpler install. If you already have a 220V circuit available, either model works.

What does an inverter heat pump do differently?

A standard heat pump compressor runs at a fixed speed - fully on or fully off. An inverter compressor varies its speed based on how much heating or cooling is needed at any given moment. When the pool is close to its target temperature, the inverter unit runs at low power rather than cycling off completely. The result is quieter operation, lower electricity use during maintenance heating, and reduced wear on the compressor over time. The Madimack InverECO models and FibroPool FH235-i all use inverter compressors.

Do these heat pumps work for above ground pools?

The FibroPool FH120, FH135, FH220, FH235-i, and FH255 are all compatible with above ground pools. The Madimack InverECO series and Hayward HeatPro 50K are designed for inground pools. Use the pool type filter on this page to narrow the options to above ground or inground models.

How long does it take a heat pump to heat a small pool?

Heat pumps heat pools gradually - typically raising water temperature by 1 to 3 degrees Fahrenheit per hour depending on BTU output, outside air temperature, and pool volume. For a 7,500-gallon pool starting at 65 degrees with a target of 82 degrees, a 35,000 BTU unit will generally take 8 to 14 hours of running time to reach temperature. Heat pumps are most efficient as maintenance heaters - once the pool is at your target temperature, they use relatively little energy to hold it there. For fast one-time heat-up, a gas heater is the faster option.

Do heat pumps work in cold weather?

Heat pumps extract heat from the surrounding air, so they become less efficient as outdoor temperatures drop. Most models in this collection operate down to around 45 to 50 degrees Fahrenheit, though output decreases significantly below 55 degrees. For pools used primarily in warm months in climates that stay above 60 degrees, a heat pump is an excellent choice. For cold-climate use or early and late-season swimming when air temperatures regularly dip below 50 degrees, a gas heater will perform more reliably.

Do you offer installation?

Yes. Visit our installation support page for details on connecting with a licensed installer in your area. Heat pump installation requires integration with your pool's existing plumbing and a dedicated electrical circuit - both of which a licensed pool or HVAC professional can handle.