Quick verdict
The high-output gas heater for large pools and fast on-demand heat. Get the gas supply and venting right, use a cover, and it'll never leave you cold.
Ideal for
- Large pools
- Fastest possible heat-up
- On-demand heating in any weather
Not ideal for
- Small pools (oversized)
- Low-running-cost, season-long heating (heat pump)
The full picture
When the pool is large or you want the fastest possible heat-up, Raypak's 266,000 BTU digital heater is a long-standing favorite. Big gas output means it doesn't care about cold air and warms a lot of water quickly — ideal for occasional-use large pools or anyone who wants to heat on demand. It's a serious gas appliance requiring a properly sized gas line, venting, and clearances, and the running cost scales with that output, so a cover is your friend. Reliable, straightforward, and built for real heating power.
Raypak 266,000 BTU Digital Natural Gas Heater at a glance
- Heater type
- Gas
- Fuel
- Natural gas
- Heating output (BTU/hr)
- 266,000
- Heats spa
- Yes
- Heat exchanger
- Copper
- Pool type
- In-ground pool / spa
- Notable feature
- High-output gas heat for large pools; digital control
Source: Compiled from manufacturer specifications, retailer listings, and aggregated owner feedback. Specs and prices change — confirm with the retailer before buying.
This is a research-based review — our analysis draws on manufacturer specifications, manuals, warranty terms, and verified owner feedback rather than our own hands-on testing, and we note where a detail couldn't be confirmed. How we review
The in-depth review
When the pool is large or you simply want the fastest possible heat-up, the Raypak 266,000 BTU digital heater has been a go-to for years. Big gas output, straightforward operation, proven platform.
Why it's a workhorse
266,000 BTU is a lot of heating power, and it doesn't care what the air is doing — gas heats fast in any weather. That makes it ideal for large pools, or for anyone who heats on demand and wants to reach temperature quickly rather than waiting out a heat pump. The digital thermostat keeps operation simple, and Raypak's platform is widely serviced with parts readily available.
The cost and install reality
Output that big consumes fuel to match, so running cost is real — a solar cover is genuinely your friend here to avoid heating the sky. It also demands a properly sized gas line, correct venting, and clearances; this is a serious appliance and a professional installation, not a weekend project.
Performance breakdown
Research-based editorial judgments from specs, warranty terms, and verified owner feedback — not lab measurements. How we score
Pros and cons
What works
- Huge, fast heating output
- Works in any weather
- Simple digital thermostat
- Proven, widely-serviced platform
What doesn't
- High fuel consumption at full output
- Needs a robust gas supply and venting
- Oversized for small pools
- Professional install required
Best alternatives to Raypak 266,000 BTU Digital Natural Gas Heater
FibroPool
FibroPool FH255 55,000 BTU Heat Pump
Best value heat pump
The value heat pump — strong efficiency (COP 5.92), titanium core, and a price that undercuts the big brands for small-to-mid pools.
FibroPool
FibroPool FH285-i Inverter Heat Pump (62,000 BTU)
Best inverter value
An inverter heat pump at a non-inverter price — variable output for quieter, steadier, more efficient heating with Wi-Fi control.
Hayward
Hayward Universal H-Series 150K Natural Gas Heater
Best gas heater
A do-anything gas heater — universal left/right connections, cupro-nickel exchanger, and low-NOx burners for reliable fast heat.
Pentair
461059
Pentair
Pentair MasterTemp 125K Natural Gas Heater
Best for spas / fast heat
A compact, fast gas heater — instant on-demand heat for small pools and spas, with low-NOx emissions and quiet operation.
Frequently asked questions
Is 266,000 BTU too much for my pool?
For small pools, yes — you'd pay for output you can't use. It shines on large pools or where fast heat-up matters. Size against surface area and the manufacturer's chart.
What does a gas heater this size need to run?
A correctly sized natural-gas line, proper venting and clearances, and electrical for the controls. This is a professional installation, not a DIY plug-in.
How fast does it heat compared to a heat pump?
Much faster — gas heats on demand regardless of air temperature, while a heat pump warms gradually. The tradeoff is running cost: gas burns fuel the whole time.
Natural gas or propane?
This is the natural-gas model; Raypak makes propane versions too. Match the heater to the fuel you have available before ordering.
Is it reliable?
Raypak’s digital heaters are a long-standing, widely-serviced platform with good parts availability — a big part of why they remain a popular large-pool choice.
Do I really need a cover with it?
Strongly recommended. At this output, heating an uncovered pool means a lot of that fuel warms the air above the water overnight. A cover cuts running cost dramatically.