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Browse one of the largest selection of pool products.

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400,000 BTU Pool Heaters

For pool owners who don't want to wait and enjoy a heated pool, or need an extra boost of power, 400,000 BTU pool heaters will get the job done in a pinch. These heavy-duty heaters are designed for heating speed and efficiency. And despite the power, a few of the 400,000 BTU heaters at Pool Express are designed to be eco-friendly, for the environmentally conscious pool owner.
Swimming pool heaters are rated according to a measurement known as British Thermal Units, or BTU. One BTU is capable of raising the temperature of 1lb of water by 1 degree Fahrenheit. This means the more BTUs a pool heater produces, the faster it will heat the water in your swimming pool. And 400,000 BTUs is more than enough power. Pool heaters with 400,000 BTUs are a safe bet to quickly heat any sized swimming pool. The pool heater should always be somewhat higher than the actual pool surface area, and the desired temperature rise required. But because there's no such thing as 'oversizing' a pool heater, pool owners typically choose a 400K BTU heater for their fast heating speed.

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Hayward Natural Gas Pool Heater Uni H-Series 400K BTU H400FDN

Hayward Natural Gas Pool Heater Uni H-Series 400K BTU H400FDN

4 (3 Reviews)

Get the Hayward Natural Gas Pool Heater Uni H-Series 400 KBTU H400FDN and other swimming pool heaters for less at Pool Express

Hayward Propane Pool Heater 400K BTU H400FDP

Hayward Propane Pool Heater 400K BTU H400FDP

Get the Hayward Propane Pool Heater H400K H400FDP and other swimming pool heaters for less at Pool Express

Jandy Natural Gas Pool Heater 400K BTU LXI400N

Jandy Natural Gas Pool Heater 400K BTU LXI400N

Get the Jandy Natural Gas Pool Heater 400K BTU LXI400N and other swimming pool heaters for less at Pool Express

Jandy Propane Pool Heater 400K BTU Copper LXI400P

Jandy Propane Pool Heater 400K BTU Copper LXI400P

4.5 (2 Reviews)

Get the Jandy Propane Pool Heater 400K BTU Copper LXI400P and other swimming pool heaters for less at Pool Express

Pentair MasterTemp Propane Pool Heater 400K BTU 460737

Pentair MasterTemp Propane Pool Heater 400K BTU 460737

Get the Pentair MasterTemp Propane Pool Heater 400K BTU 460737 and other swimming pool heaters for less at Pool Express

Raypak Natural Gas Commercial Pool Heater ASME 400K BTU  009271

Raypak Natural Gas Commercial Pool Heater ASME 400K BTU 009271

Get the Raypak Natural Gas Pool Heater 9271 and other swimming pool heaters for less at Pool Express

Raypak Natural Gas Commercial Pool Heater Low NOx ASME 400K BTU 009295

Raypak Natural Gas Commercial Pool Heater Low NOx ASME 400K BTU 009295

Get the Raypak Natural Gas Pool Heater 9295 and other swimming pool heaters for less at Pool Express

Raypak RP-2100 Natural Gas Pool Heater 399K BTU 009219

Raypak RP-2100 Natural Gas Pool Heater 399K BTU 009219

Get the Raypak Natural Gas Pool Heater 9219 and other swimming pool heaters for less at Pool Express

Raypak RP-2100 Natural Gas Pool Heater 399K BTU 009243

Raypak RP-2100 Natural Gas Pool Heater 399K BTU 009243

Get the Raypak Natural Gas Pool Heater 9243 and other swimming pool heaters for less at Pool Express

Raypak RP2100 Natural Gas Pool Heater 399K BTU 009965

Raypak RP2100 Natural Gas Pool Heater 399K BTU 009965

1 (1 Reviews)

Get the Raypak Natural Gas Pool Heater 399K BTU 009965 and other swimming pool heaters for less at Pool Express

Raypak RP2100 Propane Pool Pool Heater 399K BTU 009977

Raypak RP2100 Propane Pool Pool Heater 399K BTU 009977

Get the Raypak Propane Pool Pool Heater 399K BTU 009977 and other swimming pool heaters for less at Pool Express

Sta-Rite Max-E-Therm Natural Gas Pool Heater 400K BTU SR400NA

Sta-Rite Max-E-Therm Natural Gas Pool Heater 400K BTU SR400NA

4.3 (3 Reviews)

Get the Sta-Rite Natural Gas Pool Heater SR400NA and other swimming pool heaters for less at Pool Express

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