Raypak vs Hayward vs Pentair
The three names every gas-heater search ends up comparing. What each one publishes, what none of them do, and which question actually separates them.
Quick picks
One heater per brand, each the model its maker sells online in the class buyers actually compare. Ranked on what is published, not on badge.
| # | Product | Best for | Price |
|---|---|---|---|
| 1 |  Raypak: the stated-efficiency pick Raypak Digital Natural Gas Pool Heater 336,000 BTU/hr and an 82% figure the listings actually print. The benchmark. | Heating fast and occasionally, rather than holding a temperature | |
| 2 |  Pentair: the fast, quiet pick Pentair MasterTemp 400 Natural Gas Pool Heater 400,000 BTU/hr, low NOx, described as the quiet one. No efficiency percentage in the listings. | A full-size pool heated on demand, when you want the largest gas class | |
| 3 |  Hayward: the small-line pick Hayward Universal H-Series 150,000 BTU Natural Gas Heater 150,000 BTU/hr with a cupro nickel exchanger as standard. Half the gas demand of the other two. | A modest pool where the gas supply, not the heater, is the real constraint | |
| 4 |  The answer if none of these is right Hayward HeatPro Pool Heat Pump A heat pump at about $10.75 per million BTU, for anyone who holds a temperature rather than heating on demand. | Lowest running cost per degree when you want real temperature control |
#ad We earn a commission if you buy through this link, at no extra cost to you. It never changes the ranking. How this site is funded. Prices last checked October 18, 2026.
The honest headline
Across the three brands, the published specifications are closer than the marketing suggests, and the difference that actually matters is not the badge on the cabinet. It is the size class you pick, and the gas line that class needs. Two 400,000 BTU/hr heaters from different makers have far more in common with each other than either has with a 150,000 BTU/hr unit wearing the same logo.
So this page does two things. It sets the three brands side by side on what each publishes, and then it says plainly which of those rows should decide your purchase.
Side by side, on what is published
| Raypak 336 Digital | Hayward H-Series 150 | Pentair MasterTemp 400 | |
|---|---|---|---|
| Input rating | 336,000 BTU/hr | 150,000 BTU/hr | 400,000 BTU/hr |
| Efficiency stated | 82% in listings | No percentage for current part | No percentage |
| Delivered per hour (at stated or 82%) | 275,520 BTU | 123,000 BTU | 328,000 BTU |
| Hours: 20,000 gal, +10°F | About 6 | About 14 | About 5 |
| Exchanger | Copper fin tube, polymer headers | Cupro nickel, standard | Not stated in listings |
| Low NOx | Yes | Yes | Yes |
| Gas demand | High | Under half the others | Highest |
| Propane version sold | Yes | Yes | Yes |
Every figure is as published in the manufacturer or retail listing named on each product's card below, and each is tiered there by source. Where no efficiency is stated we compute at 82%. Nothing in this table was measured by us.
Raypak
The one of the three whose listings state an efficiency figure outright, which is why it is the benchmark across this site. Copper fin-tube exchanger with polymer headers, digital controls, and a 336,000 BTU/hr input that puts a full-size pool ten degrees up in about six hours. On published information it is the most accountable of the three. The full Raypak review goes through what that does and does not tell you.
Hayward
The pick on this page is deliberately the smaller class, because that is where Hayward’s widely sold unit sits and because it changes the decision. A 150,000 BTU/hr input asks less than half as much of a gas line, and cupro nickel is listed as the standard exchanger rather than an upgrade. Neither Hayward nor the current W3HS150FDN listings state an efficiency percentage — an 84% figure seen for the older H150FDN does not carry over — so we run it at 82%, like the Pentair. It is slow — about fourteen hours for the same job — and it is often the only one of the three an existing line will feed.
Pentair
The largest class of the three and, by the listings’ own description, the quiet one. Low-NOx certified, 400,000 BTU/hr, about five hours for the reference job. What it does not give you is a percentage: the efficiency is described as best in class without a number, which means we run it at the same 82% as the Raypak and cannot tell you it is better or worse. The MasterTemp 400 review covers what is and is not published about it.
This page compares three brands on gas heaters specifically. If your question is broader — who makes what across gas, propane and heat pumps, and which manufacturers publish anything you can hold them to — our brand comparison covers six of them, including AquaCal, FibroPool and Jandy.
Which row should decide it
Not the brand. Between the two large units the published differences are a percentage point of efficiency one of them does not state, a noise claim, and an hour of heat-up. Those are real but small, and the right way to choose between them is price and dealer support on the day.
The gas line. A 336,000 or 400,000 BTU/hr heater needs a supply most houses were not piped for, and upsizing a run can cost more than the heater. If that is your situation, the Hayward 150 is not the budget option, it is the only option, and you should price the line before you price the heater.
Whether gas is right at all. All three are on-demand machines. If you hold a temperature across a season, the running-cost gap to a heat pump — about $28.36 against about $10.75 per million BTU delivered — compounds every day. That comparison is here.
The purchase before any of them
Every hour a gas heater runs is fuel. About 70% of a pool’s heat loss is evaporation, and a cover on the water overnight is what stops the heater re-doing the same job every morning. The gas roundup ranks these three with the propane option and the sizing math, and the cover picks are where we would spend first.
Every pick, in detail
What each one publishes, what is good and bad about it, and — the section this category usually omits — what we could not judge without owning one.
Raypak Digital Natural Gas Pool Heater
The right answer when speed matters more than running cost — a weekend pool you want warm on Friday afternoon rather than one you hold at temperature all season. At the assumptions we publish, gas costs roughly two and a half times what a heat pump costs per delivered BTU, and it will get there in a fifth of the time. Buy the speed if you need the speed.
Best for Heating fast and occasionally, rather than holding a temperature
| Type | Natural gas or propane fired, digital controlThe manufacturer publishes no retrievable specification sheet; figure is as listed at retail. | Retail listing |
|---|---|---|
| Rating convention | Rated by BTU/hr INPUTA 400,000 BTU gas heater burns 400,000 BTU an hour and delivers roughly 82% of it. Do not compare that number directly against a heat pump's output rating. | Published standard |
| Cost per million BTU delivered | About $28.36 at our published assumptionsUS average residential natural gas at $24.09/Mcf (EIA, June 2026) and an assumed 82% thermal efficiency. | Our arithmetic |
- Fast — hours rather than most of a day on a full-size pool
- Works the same in cold air, unlike a heat pump
- Lower purchase price than a heat pump of equivalent real output
- Roughly two and a half times a heat pump's cost per delivered BTU
- Needs a gas line sized for it, which is often the real cost
- Propane instead of natural gas raises the running cost by about a quarter again
- The efficiency this specific unit achieves in service
- Heat exchanger life against your water chemistry
- Whether your existing gas supply can feed it without an upgrade
These need a unit in hand across a season. We do not have one, so we do not have an opinion worth printing on them.
#ad We earn a commission if you buy through this link, at no extra cost to you. It never changes the ranking. How this site is funded. Prices last checked October 18, 2026.
Pentair MasterTemp 400 Natural Gas Pool Heater
The third name in every gas-heater comparison, and the one the listings describe as the quiet one. It is a 400,000 BTU/hr input heater, low-NOx certified, which puts it in the same class as the biggest Raypak — and therefore in the same speed bracket: hours rather than a day. Pentair does not state a thermal efficiency percentage in the listings we read, so we run it at the 82% we assume for gas generally.
Best for A full-size pool heated on demand, when you want the largest gas class
| Rated input | 400,000 BTU/hrGas convention: fuel burned per hour, not heat delivered. Delivered heat is this figure times the thermal efficiency. | Retail listing |
|---|---|---|
| Emissions | Low NOx certified | Retail listing |
| Thermal efficiency | Not stated as a percentage in the listings we readThe listings say best-in-class efficiency without a number. We run it at 82%, the assumption we use for every gas heater on the site, and would revise it if Pentair published a figure we could cite. | Retail listing |
| Cost per million BTU delivered | About $28.36 at 82% efficiencyUS average residential natural gas at $24.09/Mcf (EIA, June 2026). | Our arithmetic |
- Largest common residential gas class, so the fastest heat-up on this site
- Low NOx certified, so it is permitted in the air districts that require it
- Described across listings as noticeably quieter than the older gas designs
- Roughly two and a half times a heat pump's cost per delivered BTU
- 400,000 BTU/hr demands a gas supply most houses were not piped for
- No thermal efficiency percentage in the listings, so the efficiency claim is unverifiable
- Real delivered efficiency in service
- Heat exchanger life against your water chemistry
- Whether your gas meter and line can feed it without an upgrade
These need a unit in hand across a season. We do not have one, so we do not have an opinion worth printing on them.
#ad We earn a commission if you buy through this link, at no extra cost to you. It never changes the ranking. How this site is funded. Prices last checked October 18, 2026.
Hayward Universal H-Series 150,000 BTU Natural Gas Heater
The gas heater for a pool that does not need 336,000 BTU an hour thrown at it. At 150,000 BTU/hr of input it is under half the fire of a full-size unit, which costs you speed and buys you something people discover too late: a much smaller gas supply to feed. On a modest inground pool or a big above-ground one, that is often the difference between using the gas line you already have and paying to upsize it.
Best for A modest pool where the gas supply, not the heater, is the real constraint
| Rated input | 150,000 BTU/hrHayward publishes this as a BTU/hr rating, in the gas convention: fuel burned per hour, not heat delivered into the water. | Manufacturer |
|---|---|---|
| Current part number | W3HS150FDN, which Hayward's listing states replaces the H150FDNSame heater class, current SKU, with the OmniX control. The older H150FDN part number still appears in older reviews and stock. | Retail listing |
| Heat exchanger | Standard cupro nickelCupro nickel is the corrosion-resistant option on most gas heaters and a paid upgrade on some. Hayward lists it as standard on this one. | Manufacturer |
| Thermal efficiency | Not stated for the current W3HS150FDNConfirmed on Hayward's own product page, read 17 October 2026: there is no thermal efficiency percentage anywhere on it. The only efficiency-shaped figure is a claim of savings of 'up to 18%', which refers to reduced PUMP run time rather than to combustion. An 84% figure circulated in retail copy for the older H150FDN; it does not appear for the current part, so we no longer attach it and run this heater at the 82% we assume for gas generally. | Manufacturer |
| Water flow window | Min 20, max 125Quoted exactly as Hayward publishes it — the specification table does not state the unit, though gallons per minute is the convention and the figures only make sense that way. Hayward advises keeping flow above the minimum with allowance for a dirty filter, to protect the exchanger. | Manufacturer |
| Connections | 2 in x 2-1/2 in CPVC unions | Manufacturer |
| Electrical | 120/240V, 60 Hz single phase, 5.5 circuit amps, 15 A max breakerHayward's table also carries a 'Power: 44 kW' row, which cannot describe this appliance: 5.5 A at 240 V is about 1.3 kW, and 44 kW would not sit behind a 15-amp breaker. We read it as a data-entry artifact and flag it rather than repeat it. | Manufacturer |
| Warranty | 1 year parts, no laborAt the shorter end of this category. For contrast, FibroPool states a Limited Lifetime warranty and TURBRO gives 2 years on the machine with 5 on the compressor, both on much cheaper units. | Manufacturer |
| Cost per million BTU delivered | About $28.36 at our 82% assumptionUS average residential natural gas at $24.09/Mcf (EIA, June 2026) divided by 82%, the same assumption we apply to every gas heater without a published efficiency figure. | Our arithmetic |
- Roughly half the gas demand of a full-size heater, which is often what decides the install
- Cupro nickel heat exchanger listed as standard rather than as an upgrade
- Low NOx certified, so it is permitted in the air districts that require it
- Slow for a gas heater: about 14 hours to lift 20,000 gallons ten degrees
- Still gas, so still roughly two and a half times a heat pump's cost per delivered BTU
- Hayward publishes no thermal efficiency figure for it on its own product page
- The thermal efficiency it actually delivers — no figure is published for the current part
- How the cupro nickel exchanger holds up against your water chemistry
- Whether your gas meter and line can feed it without an upgrade
These need a unit in hand across a season. We do not have one, so we do not have an opinion worth printing on them.
#ad We earn a commission if you buy through this link, at no extra cost to you. It never changes the ranking. How this site is funded. Prices last checked October 18, 2026.
Hayward HeatPro Pool Heat Pump
If you are heating a pool with electricity, this is the shape of machine to do it with. A heat pump moves heat instead of making it, and at the assumptions we publish it delivers a million BTU into the water for about a fifth of what an electric resistance heater costs to deliver the same. It is slower than gas and it fades as the air gets colder, which is exactly when you want it — that trade is the whole decision.
Best for Lowest running cost per degree when you want real temperature control
| Type | Air-source heat pumpThe manufacturer publishes no retrievable specification sheet; figure is as listed at retail. | Retail listing |
|---|---|---|
| Rating convention | Rated by BTU/hr OUTPUTThis is the trap in the category. Gas heaters are rated by fuel INPUT, heat pumps by heat OUTPUT. A 140,000 BTU heat pump and a 140,000 BTU gas heater do not deliver the same heat. | Published standard |
| Cost per million BTU delivered | About $10.75 at our published assumptionsUS average residential electricity at 18.34 cents/kWh (EIA, June 2026) and an assumed COP of 5.0. Both are substitutable on our running-cost calculator. | Our arithmetic |
- Cheapest running cost per delivered BTU of any controllable heater
- No gas line, no combustion, no flue
- Holds a set temperature rather than depending on the weather
- Slow — expect most of a day to move a full-size pool ten degrees
- Efficiency falls with air temperature, so it is weakest in the shoulder season
- High purchase price against a gas heater of comparable output
- The COP this specific unit achieves at your conditions
- Compressor and control-board longevity
- Noise at the distance your deck actually sits from it
These need a unit in hand across a season. We do not have one, so we do not have an opinion worth printing on them.
#ad We earn a commission if you buy through this link, at no extra cost to you. It never changes the ranking. How this site is funded. Prices last checked October 18, 2026.
Questions people actually ask
Is Raypak better than Hayward for pool heaters?
Is Pentair MasterTemp better than Raypak?
Which pool heater brand lasts longest?
Do all three come in propane versions?
- Average retail price of electricity to US residential customers: 18.34 cents/kWh, June 2026U.S. Energy Information Administration · read 2026-09-02
- US residential natural gas price: $24.09 per thousand cubic feet, June 2026U.S. Energy Information Administration · read 2026-09-02
- US residential propane price: $2.674 per gallon, week ending 30 March 2026U.S. Energy Information Administration · read 2026-09-02
- Energy content conversion factors: 3,412 BTU per kWh, 1,036 BTU per cubic foot of natural gas, 91,452 BTU per gallon of propaneU.S. Energy Information Administration · read 2026-09-02
- U.S. Department of Energy pool-energy figures (evaporation share, BTU per pound evaporated, cover savings, recommended temperatures, wind effect)Recreonics, reproducing and attributing the U.S. Department of Energy · read 2026-09-02
- Pool heater roundup: the 8.33 BTU per gallon per °F figure, attributed on the page to Alicia Toedter of Leslie'sBob Vila · read 2026-09-02
Every URL above was fetched and returned content on the date shown. Where a figure is ours rather than somebody else’s, the arithmetic is on the page and on the methodology page. If you find an error in it, we would genuinely like to know.
Read next
Pool heater brands, compared
Hayward, Pentair, Raypak, Jandy, AquaCal and FibroPool at brand level: what each builds, what each publishes, and which to shortlist.
Gas pool heaters worth buying
Raypak, Hayward and Pentair gas heaters ranked, with the natural gas and propane arithmetic, the rating trap, and why the gas line usually decides which one you can actually have.
Raypak pool heater review
The Raypak 336 Digital on the record: a stated 82% efficiency, six hours for a full-size pool, a gas demand most houses were not piped for, and the questions no listing answers.
Pentair MasterTemp 400 review
The MasterTemp 400 in natural gas and propane: a 400,000 BTU/hr input, about five hours for a full-size pool, low-NOx certified, and an efficiency claim with no percentage attached.
Heat pump vs gas pool heater
The two options priced per delivered BTU and timed on the same pool, with the one question that decides which trade suits you.
What size pool heater do I need?
How to size a heater from your pool's actual energy requirement, the input-versus-output rating trap, and why the answer gets smaller once you own a cover.
Hayward Universal H-Series review
Hayward's 150,000 BTU gas heater on the record: cupro nickel as standard, a published flow window, one year of parts cover, a power rating that cannot be right, and no thermal efficiency figure anywhere.