Reviews

Hayward H250 Review: The Right Size Gas Heater

A Hayward H-Series 250,000 BTU natural gas pool heater review covering coverage up to 750 sq ft, low NOx certification, running costs and when to size up or down.

Please read: This content is researched for general information only and is not professional, medical, or veterinary advice. Every situation is different, so use your own judgment and double-check before acting, especially when adding chemicals or feeding and treating animals. Consult a qualified professional when in doubt. This page also contains affiliate links; we may earn a small commission at no extra cost to you.

Rated for pools and spas up to 750 square feet, which covers most of what people actually own.

The verdict: For a typical residential inground pool, the 250,000 BTU H-Series is the size that fits, and it costs eleven hundred dollars less than the 400,000 BTU version people often buy by mistake. Buy it if your pool is up to around 750 square feet of surface and you want heat on demand in any weather. Skip it if running cost is your priority, because gas is the most expensive heat per degree and a heat pump will halve your bills or better.

Best Sized Gas Heater for a Normal Pool

Hayward H-Series Natural Gas Pool Heater for Inground Pools, 250,000 BTU

~$3,999

A 250,000 BTU natural gas pool and spa heater rated for up to 750 square feet, with a digital LED control panel, low NOx certification and side selectable gas and electric connections.

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Specifications

Output 250,000 BTU natural gas
Coverage Inground pools and spas up to 750 square feet per Hayward
Control Digital LED display with water temperature monitoring
Gas connection Built in three quarter inch connection, left or right side
Emissions Certified for low NOx
Design Cupro nickel and polymer construction options across the H-Series range

Specifications above come from Hayward's published specifications. Treat pricing as approximate, since Amazon pricing moves.

What it does well

  • It matches the size of a normal residential pool, which is the single most important thing about a heater and the thing most often got wrong.
  • Gas heating is unaffected by air temperature, so an early season weekend is heatable in a way a heat pump cannot match.
  • Side selectable connections make retrofitting onto an existing equipment pad far less disruptive.
  • Low NOx certification, which is a requirement in a growing number of jurisdictions.

Where it falls short

  • Gas is expensive per degree. A season of heating an uncovered pool can cost more than the heater did, and owners consistently discover this in the first bill.
  • A gas appliance needs an adequate gas supply and a properly sized line, which is a separate cost and a separate trade.
  • Installation is licensed work with permit and inspection, and improper venting or combustion air creates a carbon monoxide risk.
  • Salt water pools are hard on heater internals, so if you run a salt system, look carefully at which heat exchanger material you are buying.

What owners report

Published owner reports are positive on heating performance and on the control panel, and the recurring theme in problems is again installation rather than product: gas supply sizing, clearances and venting. Owners who used a qualified pool heater installer report far fewer issues than those who used a general contractor.

Longevity reports cluster around water chemistry. Owners who kept their water balanced describe long service lives, and owners who ran aggressive or unbalanced water describe heat exchanger problems. That is consistent across gas heater brands and is the strongest argument for testing your water regularly.

Who it suits

  • Typical residential inground pools up to around 750 square feet of surface.
  • Anyone who wants to heat for a specific weekend rather than a whole season.
  • Cold climate pools where a heat pump cannot deliver in spring.

Who should skip it

  • Very large pools, which need the 400,000 BTU model.
  • Owners whose priority is low running cost, who should look at a heat pump.
  • Properties without natural gas, unless you are prepared for propane consumption at this rate.

Alternatives worth considering

Smaller Pools

Hayward H-Series Natural Gas Pool Heater for Inground Pools, 200,000 BTU

~$3,699

Rated for up to 600 square feet and three hundred dollars less. If your pool is genuinely small, this is the right member of the family and there is no benefit to buying larger.

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Cheaper Similar Output

Raypak 266,000 BTU Digital Electronic Ignition Natural Gas Pool Heater

~$3,179

Similar output for around eight hundred dollars less, with intermittent spark ignition so the pilot only lights on a call for heat. A well established alternative brand in the same category.

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For Low Running Cost

DR. Infrared Heater DR-1100HP Full DC Inverter 110,000 BTU Pool Heat Pump

~$4,199

Costs slightly more to buy and a fraction to run, at the price of slow heating and poor performance in cold air. The right technology if you heat all season rather than on demand.

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Keep reading

This review draws on published specifications, manufacturer figures and the consensus of verified owner reviews. We have not tested this product ourselves, and we say so rather than implying otherwise. As an Amazon Associate we earn from qualifying purchases.

Frequently Asked Questions

Is 250,000 BTU enough for my pool?

Hayward rates it for pools and spas up to 750 square feet of surface, which covers most residential pools. The honest way to check is to calculate from your own surface area and desired temperature rise. Our heater size calculator does that, and it also shows why a bigger heater is not automatically better.

How much does gas pool heating cost to run?

It depends on your gas rate, your target temperature and, more than anything, whether you use a cover. Uncovered pools lose most of their heat overnight through the surface. Our pool cost calculator will estimate a season for your pool, and the cover line is usually the one that changes the answer.

Will a salt water pool damage a gas heater?

Salt water is more aggressive towards metal components than traditionally chlorinated water, and heat exchanger material matters. Check what the specific model uses and keep your water balanced, because unbalanced water damages heaters faster than salt does. Our Langelier saturation index page explains what balanced actually means.

Do I need a permit for a pool heater?

Almost always, for both the gas work and the electrical connection. An inspection protects you: gas appliances that are incorrectly vented or starved of combustion air can produce carbon monoxide. Use a licensed installer and keep the paperwork for your insurer.

Heater or cover first?

Cover, every time. A solar cover costs a small fraction of a heater and reduces the heat loss the heater is fighting. Owners who install a heater without a cover are the ones who report shocking gas bills. Our solar cover comparison covers the choices.

Taking care of a pool?

Use our free calculators and guides to get every number right.

Pool Care Planner: $39